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Cloning – Wikipedia

Cloning is the process of producing genetically identical individuals of an organism either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments (molecular cloning). Beyond biology, the term refers to the production of multiple copies of digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word kln, “twig”, referring to the process whereby a new plant can be created from a twig. In botany, the term lusus was traditionally used.[1] In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a “long o” instead of a “short o”.[2][3] Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Cloning is a natural form of reproduction that has allowed life forms to spread for hundreds of millions of years. It is the reproduction method used by plants, fungi, and bacteria, and is also the way that clonal colonies reproduce themselves.[4][5] Examples of these organisms include blueberry plants, hazel trees, the Pando trees,[6][7] the Kentucky coffeetree, Myricas, and the American sweetgum.

Molecular cloning refers to the process of making multiple molecules. Cloning is commonly used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. To amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. However, a number of other features are needed, and a variety of specialised cloning vectors (small piece of DNA into which a foreign DNA fragment can be inserted) exist that allow protein production, affinity tagging, single stranded RNA or DNA production and a host of other molecular biology tools.

Cloning of any DNA fragment essentially involves four steps[8]

Although these steps are invariable among cloning procedures a number of alternative routes can be selected; these are summarized as a cloning strategy.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector (piece of DNA). The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation, optical injection and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. Additionally, the cloning vectors may contain colour selection markers, which provide blue/white screening (alpha-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies must be required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing.

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders).[9] In this technique a single-cell suspension of cells that have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies, each arising from a single and potentially clonal distinct cell. At an early growth stage when colonies consist of only a few cells, sterile polystyrene rings (cloning rings), which have been dipped in grease, are placed over an individual colony and a small amount of trypsin is added. Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Somatic-cell nuclear transfer, known as SCNT, can also be used to create embryos for research or therapeutic purposes. The most likely purpose for this is to produce embryos for use in stem cell research. This process is also called “research cloning” or “therapeutic cloning.” The goal is not to create cloned human beings (called “reproductive cloning”), but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source.[10]

Therapeutic cloning is achieved by creating embryonic stem cells in the hopes of treating diseases such as diabetes and Alzheimer’s. The process begins by removing the nucleus (containing the DNA) from an egg cell and inserting a nucleus from the adult cell to be cloned.[11] In the case of someone with Alzheimer’s disease, the nucleus from a skin cell of that patient is placed into an empty egg. The reprogrammed cell begins to develop into an embryo because the egg reacts with the transferred nucleus. The embryo will become genetically identical to the patient.[11] The embryo will then form a blastocyst which has the potential to form/become any cell in the body.[12]

The reason why SCNT is used for cloning is because somatic cells can be easily acquired and cultured in the lab. This process can either add or delete specific genomes of farm animals. A key point to remember is that cloning is achieved when the oocyte maintains its normal functions and instead of using sperm and egg genomes to replicate, the oocyte is inserted into the donor’s somatic cell nucleus.[13] The oocyte will react on the somatic cell nucleus, the same way it would on sperm cells.[13]

The process of cloning a particular farm animal using SCNT is relatively the same for all animals. The first step is to collect the somatic cells from the animal that will be cloned. The somatic cells could be used immediately or stored in the laboratory for later use.[13] The hardest part of SCNT is removing maternal DNA from an oocyte at metaphase II. Once this has been done, the somatic nucleus can be inserted into an egg cytoplasm.[13] This creates a one-cell embryo. The grouped somatic cell and egg cytoplasm are then introduced to an electrical current.[13] This energy will hopefully allow the cloned embryo to begin development. The successfully developed embryos are then placed in surrogate recipients, such as a cow or sheep in the case of farm animals.[13]

SCNT is seen as a good method for producing agriculture animals for food consumption. It successfully cloned sheep, cattle, goats, and pigs. Another benefit is SCNT is seen as a solution to clone endangered species that are on the verge of going extinct.[13] However, stresses placed on both the egg cell and the introduced nucleus can be enormous, which led to a high loss in resulting cells in early research. For example, the cloned sheep Dolly was born after 277 eggs were used for SCNT, which created 29 viable embryos. Only three of these embryos survived until birth, and only one survived to adulthood.[14] As the procedure could not be automated, and had to be performed manually under a microscope, SCNT was very resource intensive. The biochemistry involved in reprogramming the differentiated somatic cell nucleus and activating the recipient egg was also far from being well understood. However, by 2014 researchers were reporting cloning success rates of seven to eight out of ten[15] and in 2016, a Korean Company Sooam Biotech was reported to be producing 500 cloned embryos per day.[16]

In SCNT, not all of the donor cell’s genetic information is transferred, as the donor cell’s mitochondria that contain their own mitochondrial DNA are left behind. The resulting hybrid cells retain those mitochondrial structures which originally belonged to the egg. As a consequence, clones such as Dolly that are born from SCNT are not perfect copies of the donor of the nucleus.

Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, cloning, or asexual propagation,[17] has been common practice in the horticultural world for hundreds of years.

The term clone is used in horticulture to refer to descendants of a single plant which were produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction.[18] As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana.[19] Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation.

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies naturally. Parts of an individual plant may become detached by fragmentation and grow on to become separate clonal individuals. A common example is in the vegetative reproduction of moss and liverwort gametophyte clones by means of gemmae. Some vascular plants e.g. dandelion and certain viviparous grasses also form seeds asexually, termed apomixis, resulting in clonal populations of genetically identical individuals.

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes,[20] fish (for example the hammerhead shark[21]), the Komodo dragon[21] and lizards. The growth and development occurs without fertilization by a male. In plants, parthenogenesis means the development of an embryo from an unfertilized egg cell, and is a component process of apomixis. In species that use the XY sex-determination system, the offspring will always be female. An example is the little fire ant (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments.

Artificial cloning of organisms may also be called reproductive cloning.

Hans Spemann, a German embryologist was awarded a Nobel Prize in Physiology or Medicine in 1935 for his discovery of the effect now known as embryonic induction, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs. In 1928 he and his student, Hilde Mangold, were the first to perform somatic-cell nuclear transfer using amphibian embryos one of the first steps towards cloning.[22]

Reproductive cloning generally uses “somatic cell nuclear transfer” (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg from which the nucleus has been removed, or to a cell from a blastocyst from which the nucleus has been removed.[23] If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this mitochondrial DNA is wholly from the cytoplasmic donor’s egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Artificial embryo splitting or embryo twinning, a technique that creates monozygotic twins from a single embryo, is not considered in the same fashion as other methods of cloning. During that procedure, a donor embryo is split in two distinct embryos, that can then be transferred via embryo transfer. It is optimally performed at the 6- to 8-cell stage, where it can be used as an expansion of IVF to increase the number of available embryos.[24] If both embryos are successful, it gives rise to monozygotic (identical) twins.

Dolly, a Finn-Dorset ewe, was the first mammal to have been successfully cloned from an adult somatic cell. Dolly was formed by taking a cell from the udder of her 6-year old biological mother.[25] Dolly’s embryo was created by taking the cell and inserting it into a sheep ovum. It took 434 attempts before an embryo was successful.[26] The embryo was then placed inside a female sheep that went through a normal pregnancy.[27] She was cloned at the Roslin Institute in Scotland by British scientists Sir Ian Wilmut and Keith Campbell and lived there from her birth in 1996 until her death in 2003 when she was six. She was born on 5 July 1996 but not announced to the world until 22 February 1997.[28] Her stuffed remains were placed at Edinburgh’s Royal Museum, part of the National Museums of Scotland.[29]

Dolly was publicly significant because the effort showed that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, can be reprogrammed to grow an entirely new organism. Before this demonstration, it had been shown by John Gurdon that nuclei from differentiated cells could give rise to an entire organism after transplantation into an enucleated egg.[30] However, this concept was not yet demonstrated in a mammalian system.

The first mammalian cloning (resulting in Dolly the sheep) had a success rate of 29 embryos per 277 fertilized eggs, which produced three lambs at birth, one of which lived. In a bovine experiment involving 70 cloned calves, one-third of the calves died young. The first successfully cloned horse, Prometea, took 814 attempts. Notably, although the first[clarification needed] clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the sheep had pathologies resembling accelerated aging. Scientists speculated that Dolly’s death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly’s early death due to respiratory infection was unrelated to deficiencies with the cloning process. This idea that the nuclei have not irreversibly aged was shown in 2013 to be true for mice.[31]

Dolly was named after performer Dolly Parton because the cells cloned to make her were from a mammary gland cell, and Parton is known for her ample cleavage.[32]

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Notable experiments include:

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissues. It does not refer to the natural conception and delivery of identical twins. The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass legislation regarding human cloning and its legality. As of right now, scientists have no intention of trying to clone people and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.[63]

Two commonly discussed types of theoretical human cloning are therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014[update]. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.[64]

There are a variety of ethical positions regarding the possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Advocates support development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants,[65] to avoid the need for immunosuppressive drugs,[64] and to stave off the effects of aging.[66] Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.[67]

Opponents of cloning have concerns that technology is not yet developed enough to be safe[68] and that it could be prone to abuse (leading to the generation of humans from whom organs and tissues would be harvested),[69][70] as well as concerns about how cloned individuals could integrate with families and with society at large.[71][72]

Religious groups are divided, with some opposing the technology as usurping “God’s place” and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.[73][74]

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die,[75][76] and while food from cloned animals has been approved by the US FDA,[77][78] its use is opposed by groups concerned about food safety.[79][80][81]

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream. Possible implications of this were dramatized in the 1984 novel Carnosaur and the 1990 novel Jurassic Park.[82][83] The best current cloning techniques have an average success rate of 9.4 percent[84] (and as high as 25 percent[31]) when working with familiar species such as mice,[note 1] while cloning wild animals is usually less than 1 percent successful.[87] Several tissue banks have come into existence, including the “Frozen Zoo” at the San Diego Zoo, to store frozen tissue from the world’s rarest and most endangered species.[82][88][89]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean ibex) were frozen in liquid nitrogen immediately after it died in 2000. Researchers are also considering cloning endangered species such as the giant panda and cheetah.

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the thylacine (Tasmanian tiger), at the time extinct for about 65 years, using polymerase chain reaction.[90] However, on 15 February 2005 the museum announced that it was stopping the project after tests showed the specimens’ DNA had been too badly degraded by the (ethanol) preservative. On 15 May 2005 it was announced that the thylacine project would be revived, with new participation from researchers in New South Wales and Victoria.

In 2003, for the first time, an extinct animal, the Pyrenean ibex mentioned above was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved frozen cell nucleus of the skin samples from 2001 and domestic goat egg-cells. The ibex died shortly after birth due to physical defects in its lungs.[91]

One of the most anticipated targets for cloning was once the woolly mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama, saying that they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.[92][93] It was noted, however that the result, if possible, would be an elephant-mammoth hybrid rather than a true mammoth.[94] Another problem is the survival of the reconstructed mammoth: ruminants rely on a symbiosis with specific microbiota in their stomachs for digestion.[94]

Scientists at the University of Newcastle and University of New South Wales announced in March 2013 that the very recently extinct gastric-brooding frog would be the subject of a cloning attempt to resurrect the species.[95]

Many such “De-extinction” projects are described in the Long Now Foundation’s Revive and Restore Project.[96]

After an eight-year project involving the use of a pioneering cloning technique, Japanese researchers created 25 generations of healthy cloned mice with normal lifespans, demonstrating that clones are not intrinsically shorter-lived than naturally born animals.[31][97] Other sources have noted that the offspring of clones tend to be healthier than the original clones and indistinguishable from animals produced naturally.[98]

Dolly the sheep was created from a six year old cell sample from a mammary gland. Because of this, she aged quicker than other naturally born animals because she was started from already aging cells. She died prematurely at six years old, not only from her age but from respiratory issues and severe arthritis.[citation needed][dubious discuss]

A detailed study released in 2016 and less detailed studies by others suggest that once cloned animals get past the first month or two of life they are generally healthy. However, early pregnancy loss and neonatal losses are still greater with cloning than natural conception or assisted reproduction (IVF). Current research is attempting to overcome these problems.[32]

Discussion of cloning in the popular media often presents the subject negatively. In an article in the 8 November 1993 article of Time, cloning was portrayed in a negative way, modifying Michelangelo’s Creation of Adam to depict Adam with five identical hands.[99] Newsweek’s 10 March 1997 issue also critiqued the ethics of human cloning, and included a graphic depicting identical babies in beakers.[100]

The concept of cloning, particularly human cloning, has featured a wide variety of science fiction works. An early fictional depiction of cloning is Bokanovsky’s Process which features in Aldous Huxley’s 1931 dystopian novel Brave New World. The process is applied to fertilized human eggs in vitro, causing them to split into identical genetic copies of the original.[101][102] Following renewed interest in cloning in the 1950s, the subject was explored further in works such as Poul Anderson’s 1953 story UN-Man, which describes a technology called “exogenesis”, and Gordon Rattray Taylor’s book The Biological Time Bomb, which popularised the term “cloning” in 1963.[103]

Cloning is a recurring theme in a number of contemporary science fiction films, ranging from action films such as Jurassic Park (1993), Alien Resurrection (1997), The 6th Day (2000), Resident Evil (2002), Star Wars: Episode II (2002) and The Island (2005), to comedies such as Woody Allen’s 1973 film Sleeper.[104]

The process of cloning is represented variously in fiction. Many works depict the artificial creation of humans by a method of growing cells from a tissue or DNA sample; the replication may be instantaneous, or take place through slow growth of human embryos in artificial wombs. In the long-running British television series Doctor Who, the Fourth Doctor and his companion Leela were cloned in a matter of seconds from DNA samples (“The Invisible Enemy”, 1977) and then in an apparent homage to the 1966 film Fantastic Voyage shrunk to microscopic size in order to enter the Doctor’s body to combat an alien virus. The clones in this story are short-lived, and can only survive a matter of minutes before they expire.[105] Science fiction films such as The Matrix and Star Wars: Episode II Attack of the Clones have featured scenes of human foetuses being cultured on an industrial scale in mechanical tanks.[106]

Cloning humans from body parts is also a common theme in science fiction. Cloning features strongly among the science fiction conventions parodied in Woody Allen’s Sleeper, the plot of which centres around an attempt to clone an assassinated dictator from his disembodied nose.[107] In the 2008 Doctor Who story “Journey’s End”, a duplicate version of the Tenth Doctor spontaneously grows from his severed hand, which had been cut off in a sword fight during an earlier episode.[108]

After the death of her beloved 14-year old Coton de Tulear named Samantha in late 2017, Barbra Streisand announced that she had cloned the dog, and was now “waiting for [the two cloned pups] to get older so [she] can see if they have [Samantha’s] brown eyes and her seriousness.” [109] The operation cost $50,000 through the pet cloning company ViaGen.

Science fiction has used cloning, most commonly and specifically human cloning, to raise the controversial questions of identity.[110][111] A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity, especially nature and nurture. The story, set in the near future, is structured around the conflict between a father (Salter) and his sons (Bernard 1, Bernard 2, and Michael Black) two of whom are clones of the first one. A Number was adapted by Caryl Churchill for television, in a co-production between the BBC and HBO Films.[112]

In 2012, a Japanese television series named “Bunshin” was created. The story’s main character, Mariko, is a woman studying child welfare in Hokkaido. She grew up always doubtful about the love from her mother, who looked nothing like her and who died nine years before. One day, she finds some of her mother’s belongings at a relative’s house, and heads to Tokyo to seek out the truth behind her birth. She later discovered that she was a clone.[113]

In the 2013 television series Orphan Black, cloning is used as a scientific study on the behavioral adaptation of the clones.[114] In a similar vein, the book The Double by Nobel Prize winner Jos Saramago explores the emotional experience of a man who discovers that he is a clone.[115]

Cloning has been used in fiction as a way of recreating historical figures. In the 1976 Ira Levin novel The Boys from Brazil and its 1978 film adaptation, Josef Mengele uses cloning to create copies of Adolf Hitler.[116]

In Michael Crichton’s 1990 novel Jurassic Park, which spawned a series of Jurassic Park feature films, a bioengineering company develops a technique to resurrect extinct species of dinosaurs by creating cloned creatures using DNA extracted from fossils. The cloned dinosaurs are used to populate the Jurassic Park wildlife park for the entertainment of visitors. The scheme goes disastrously wrong when the dinosaurs escape their enclosures. Despite being selectively cloned as females to prevent them from breeding, the dinosaurs develop the ability to reproduce through parthenogenesis.[117]

The use of cloning for military purposes has also been explored in several fictional works. In Doctor Who, an alien race of armour-clad, warlike beings called Sontarans was introduced in the 1973 serial “The Time Warrior”. Sontarans are depicted as squat, bald creatures who have been genetically engineered for combat. Their weak spot is a “probic vent”, a small socket at the back of their neck which is associated with the cloning process.[118] The concept of cloned soldiers being bred for combat was revisited in “The Doctor’s Daughter” (2008), when the Doctor’s DNA is used to create a female warrior called Jenny.[119]

The 1977 film Star Wars was set against the backdrop of a historical conflict called the Clone Wars. The events of this war were not fully explored until the prequel films Attack of the Clones (2002) and Revenge of the Sith (2005), which depict a space war waged by a massive army of heavily armoured clone troopers that leads to the foundation of the Galactic Empire. Cloned soldiers are “manufactured” on an industrial scale, genetically conditioned for obedience and combat effectiveness. It is also revealed that the popular character Boba Fett originated as a clone of Jango Fett, a mercenary who served as the genetic template for the clone troopers.[120][121]

A recurring sub-theme of cloning fiction is the use of clones as a supply of organs for transplantation. The 2005 Kazuo Ishiguro novel Never Let Me Go and the 2010 film adaption[122] are set in an alternate history in which cloned humans are created for the sole purpose of providing organ donations to naturally born humans, despite the fact that they are fully sentient and self-aware. The 2005 film The Island[123] revolves around a similar plot, with the exception that the clones are unaware of the reason for their existence.

The exploitation of human clones for dangerous and undesirable work was examined in the 2009 British science fiction film Moon.[124] In the futuristic novel Cloud Atlas and subsequent film, one of the story lines focuses on a genetically-engineered fabricant clone named Sonmi~451, one of millions raised in an artificial “wombtank,” destined to serve from birth. She is one of thousands created for manual and emotional labor; Sonmi herself works as a server in a restaurant. She later discovers that the sole source of food for clones, called ‘Soap’, is manufactured from the clones themselves.[125]

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Cloning – Wikipedia

Cloning Couture | Exploring the world of couture sewing

Thank you all for the many comments and compliments about this jacket. The finishing details are what sets French jackets apart and make this jacket unique. In addition to the custom trim, French jackets feature hand worked buttonholes, sleeves are set by hand, countless tiny stitches secure the lining and a metal chain inside the jacket allow it to drape perfectly when worn.

I think the sleeves are actually easier to set by hand and would be almost impossible to do by machine due to the unique construction methods. Although it would be easier to sew the armseye seam through all layers, I find joining only the outer fabrics together before hand basting the lining in place gives a softer, more fluid feel.

Heres an inside view of the armseye seam. Probably one if the messiest times in jacket construction. Yes, I used Pro Sheer Elegance Couture interfacing which was fused the jacket sections. Its extremely lightweight, flexible and doesnt change the drape of the tweed. Linton actually recommends doing this with their more loosely woven fabrics. Ive serged the edges of the tweed with a wide stitch but finished the seams of the lining with a narrow two thread stitch using fine thread. I like Gutermann Skala 360-U81, Invisafil by Wonderfil Threads, or 80 weight Maderia or Aurifil cotton. I use two strands of regular sewing thread, waxed and pressed, to set the sleeve. I sew the top part from the right side using tiny fell stitches and the underarm portion from the inside with a backstitch.

Notice at the point where the shoulder seam meets the sleeve seam, the seam allowances havent been caught but are allowed to float free. This allows the seam to press more smoothly and feels less rigid. Ive not included the sleeve lining; I feel I get a better result by joining only two layers of fabric at one time.

I create a sleeve head from cotton batting. Cut about 2.5 inches wide and 7 inches long. Fold along a long side about 1.5 inches from the edge, pull along the folded edge while steam pressing to curve. The folded edge is sewn along the armseye seam at the sleeve cap to provide additional shape and support.

Baste the sleeve lining just inside the armseye seam and trim away the excess fabric. Ive struggled with getting the lining over the sleeve cap evenly if the jacket is lying flat. Ive found it much easier to turn the jacket inside out and place on my dress form with a sleeve form attached. Now the jacket and sleeve are supported and its easier to manipulate the lining into position.

Pin along the seam and sew a line of tiny running stitches. Pull the gathering thread up to fit and tie a tailors knot at each end. Trim off the excess and the fabric will fold under easily along the gathering line. I set the sleeve cap first, baste, then remove the jacket from the form. The lining at the underarm is brought up and around the seam allowances.

I had originally planned for front buttons, but decided I liked the look of trim without buttons, and considered a front zipper. Botani Trimming in NYC makes custom zippers and does mail order. You select the zipper tooth size, length, color and pull. The zipper arrives in a few days and they even had chain for the hem. Finding the right zipper in a local shop would have been impossible. Just as an interesting side note, Botani sells Lampo zippers. They are made in Italy and the same brand that Chanel uses!

How to deal with the lining? I could have folded it back past the zipper teeth and stitched into place but that left the zipper teeth exposed on the inside of the jacket. In true couture fashion, I wanted to cover up that metal. Placing a length of ribbon inside the fold beefed up the edge of the silk charmeuse so it would be less likely to catch on the zipper pull. This was one time when that rigid, slightly raised edge on polyester ribbon was useful. Now zipper teeth are concealed, both inside and out.

The dreaded buttonholes next. Machine made buttonholes lack the couture finish this jacket needed. Ive experimented with countless ways to improve my hand worked version. Ive found that sewing around the buttonhole before cutting, especially in a fabric such as this, helps tremendously to keep the layers together. Marking and sewing this manually on the machine requires much twisting and turning of the fabric so I searched for an easier way. My machine sews a square buttonhole using a straight stitch so I tried that, stitching around the buttonhole twice, once at a narrow width and again a little wider.

Looks OK but I didnt like the thread buildup at the beginning and end (impossible to stop the machine from knotting the threads) plus I really wanted a keyhole buttonhole.

My Bernina does embroidery and I have digitizing software so I created a template for the buttonholes. I hooped a square of heavy muslin, stitched out the placement lines for the sleeve; then cut out a window so the stitching wouldnt get caught on the muslin. The sleeve was pinned onto the muslin. Working wrong side up worked better. The sleeve was easier to place and keep the fabric clear of the stitching area, plus the embroidery foot wouldnt get snagged on the loose fibers of the tweed. The embroidery software will insert buttonholes automatically, but I wasnt able to adjust the shape and stitch length satisfactorily. I also wasnt able to do the double rows. Mirror the image for the other sleeve and remember to cut another window so your muslin doesnt get stitched to the fabric.

There are several YouTube videos showing hand worked buttonholes if you need a review. I worked under a magnifying light and tried to keep the buttonhole stitches just inside the second row of machine stitching. It provided a nice guide for straight, narrow stitches. Buttonholes arent easy and most people say they need to work a hundreds before somewhat mastering the art. Im always trying to make mine better but these arent bad.

Ive been inspired by the photos of sheath dresses with matching jackets ( Helen Haugheys class looked wonderful) so thats next in the sewing lineup. Thanks for reading.

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Cloning Couture | Exploring the world of couture sewing

Free cloning Essays and Papers – 123helpme.com

– As years pass, more and more gadgets, machines, transportations, and foods are being improved because of the technological advancements. Even the life of humans is improved by the years, where the life expectancy is increasing because of the developed medical research, medicines, and medical equipments. However, developed biomedical methods such as cloning are controversial, and in fact 93% of all Americans oppose cloning. Because of the controversies against this practice, the United States would not open the door to reproductive cloning, and this lead to a debate between the government, and scientists and bioethicists- who are supporting human cloning…. [tags: Ethical Issues, Human Cloning]

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Dolly (sheep) – Wikipedia

Dolly (5 July 1996 14 February 2003) was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer.

Dolly was cloned by Keith Campbell, Ian Wilmut and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland, and the biotechnology company PPL Therapeutics, based near Edinburgh. The funding for Dolly’s cloning was provided by PPL Therapeutics and the Ministry of Agriculture.[2] She was born on 5 July 1996 and died from a progressive lung disease five months before her seventh birthday (the disease was not considered related to her being a clone).[3] She has been called “the world’s most famous sheep” by sources including BBC News and Scientific American.[4][5]

The cell used as the donor for the cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. On Dolly’s name, Wilmut stated “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s”.[1]

Dolly was born on 5 July 1996 and had three mothers: one provided the egg, another the DNA, and a third carried the cloned embryo to term.[6] She was created using the technique of somatic cell nuclear transfer, where the cell nucleus from an adult cell is transferred into an unfertilized oocyte (developing egg cell) that has had its cell nucleus removed. The hybrid cell is then stimulated to divide by an electric shock, and when it develops into a blastocyst it is implanted in a surrogate mother.[7] Dolly was the first clone produced from a cell taken from an adult mammal.[8][9] The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting to an embryonic totipotent state, creating a cell that can then go on to develop into any part of an animal.[10] Dolly’s existence was announced to the public on 22 February 1997.[1] It gained much attention in the media. A commercial with Scottish scientists playing with sheep was aired on TV, and a special report in Time magazine featured Dolly the sheep.[2] Science featured Dolly as the breakthrough of the year. Even though Dolly was not the first animal cloned, she received media attention because she was the first cloned from an adult cell.[11]

Dolly lived her entire life at the Roslin Institute in Midlothian.[12] There she was bred with a Welsh Mountain ram and produced six lambs in total. Her first lamb, named Bonnie, was born in April 1998.[3] The next year Dolly produced twin lambs Sally and Rosie, and she gave birth to triplets Lucy, Darcy and Cotton in 2000.[13] In late 2001, at the age of four, Dolly developed arthritis and began to walk stiffly. This was treated with anti-inflammatory drugs.[14]

On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis.[15] A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years. A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte,[16] which is a fairly common disease of sheep and is caused by the retrovirus JSRV.[17] Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease.[15] Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons.

Some in the press speculated that a contributing factor to Dolly’s death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned.[18] One basis for this idea was the finding that Dolly’s telomeres were short, which is typically a result of the aging process.[19][20] The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.[18]

In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly. The first study to review the long-term health outcomes of cloning, the authors found no evidence of late-onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded “We could find no evidence, therefore, of a detrimental long-term effect of cloning by SCNT on the health of aged offspring among our cohort.”[21][22]

After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs,[23][24] deer,[25] horses[26] and bulls.[27] The attempt to clone argali (mountain sheep) did not produce viable embryos. The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring.[28] The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development.[29][30] Making cloned mammals was highly inefficient in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts. By 2014 Chinese scientists were reported to have 7080% success rates cloning pigs[24] and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day.[31] Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.[32]

Cloning may have uses in preserving endangered species and may become a viable tool for reviving extinct species.[33] In January 2009, scientists from the Centre of Food Technology and Research of Aragon, in northern Spain announced the cloning of the Pyrenean ibex, a form of wild mountain goat, which was officially declared extinct in 2000. Although the newborn ibex died shortly after birth due to physical defects in its lungs, it is the first time an extinct animal has been cloned, and may open doors for saving endangered and newly extinct species by resurrecting them from frozen tissue.[34][35]

In July 2016, four identical clones of Dolly (Daisy, Debbie, Dianna, and Denise) were alive and healthy at nine years old.[36][37]

Scientific American concluded in 2016 that the main legacy of Dolly the sheep has not been cloning of animals but in advances into stem cell research.[38] After Dolly, researchers realised that ordinary cells could be reprogrammed to induced pluripotent stem cells which can be grown into any tissue.[39]

The first successful cloning of a primate species using the same method for producing Dolly was reported in January 2018. Two identical clones of a macaque monkey, Zhong Zhong and Hua Hua, were created by researchers in China and were born in late 2017.[40][41][42][43]

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Dolly (sheep) – Wikipedia

Cloning – Wikipedia

Cloning is the process of producing genetically identical individuals of an organism either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments (molecular cloning). Beyond biology, the term refers to the production of multiple copies of digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word kln, “twig”, referring to the process whereby a new plant can be created from a twig. In botany, the term lusus was traditionally used.[1] In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a “long o” instead of a “short o”.[2][3] Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Cloning is a natural form of reproduction that has allowed life forms to spread for hundreds of millions of years. It is the reproduction method used by plants, fungi, and bacteria, and is also the way that clonal colonies reproduce themselves.[4][5] Examples of these organisms include blueberry plants, hazel trees, the Pando trees,[6][7] the Kentucky coffeetree, Myricas, and the American sweetgum.

Molecular cloning refers to the process of making multiple molecules. Cloning is commonly used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. To amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. However, a number of other features are needed, and a variety of specialised cloning vectors (small piece of DNA into which a foreign DNA fragment can be inserted) exist that allow protein production, affinity tagging, single stranded RNA or DNA production and a host of other molecular biology tools.

Cloning of any DNA fragment essentially involves four steps[8]

Although these steps are invariable among cloning procedures a number of alternative routes can be selected; these are summarized as a cloning strategy.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector (piece of DNA). The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation, optical injection and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. Additionally, the cloning vectors may contain colour selection markers, which provide blue/white screening (alpha-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies must be required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing.

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders).[9] In this technique a single-cell suspension of cells that have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies, each arising from a single and potentially clonal distinct cell. At an early growth stage when colonies consist of only a few cells, sterile polystyrene rings (cloning rings), which have been dipped in grease, are placed over an individual colony and a small amount of trypsin is added. Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Somatic-cell nuclear transfer, known as SCNT, can also be used to create embryos for research or therapeutic purposes. The most likely purpose for this is to produce embryos for use in stem cell research. This process is also called “research cloning” or “therapeutic cloning.” The goal is not to create cloned human beings (called “reproductive cloning”), but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source.[10]

Therapeutic cloning is achieved by creating embryonic stem cells in the hopes of treating diseases such as diabetes and Alzheimer’s. The process begins by removing the nucleus (containing the DNA) from an egg cell and inserting a nucleus from the adult cell to be cloned.[11] In the case of someone with Alzheimer’s disease, the nucleus from a skin cell of that patient is placed into an empty egg. The reprogrammed cell begins to develop into an embryo because the egg reacts with the transferred nucleus. The embryo will become genetically identical to the patient.[11] The embryo will then form a blastocyst which has the potential to form/become any cell in the body.[12]

The reason why SCNT is used for cloning is because somatic cells can be easily acquired and cultured in the lab. This process can either add or delete specific genomes of farm animals. A key point to remember is that cloning is achieved when the oocyte maintains its normal functions and instead of using sperm and egg genomes to replicate, the oocyte is inserted into the donor’s somatic cell nucleus.[13] The oocyte will react on the somatic cell nucleus, the same way it would on sperm cells.[13]

The process of cloning a particular farm animal using SCNT is relatively the same for all animals. The first step is to collect the somatic cells from the animal that will be cloned. The somatic cells could be used immediately or stored in the laboratory for later use.[13] The hardest part of SCNT is removing maternal DNA from an oocyte at metaphase II. Once this has been done, the somatic nucleus can be inserted into an egg cytoplasm.[13] This creates a one-cell embryo. The grouped somatic cell and egg cytoplasm are then introduced to an electrical current.[13] This energy will hopefully allow the cloned embryo to begin development. The successfully developed embryos are then placed in surrogate recipients, such as a cow or sheep in the case of farm animals.[13]

SCNT is seen as a good method for producing agriculture animals for food consumption. It successfully cloned sheep, cattle, goats, and pigs. Another benefit is SCNT is seen as a solution to clone endangered species that are on the verge of going extinct.[13] However, stresses placed on both the egg cell and the introduced nucleus can be enormous, which led to a high loss in resulting cells in early research. For example, the cloned sheep Dolly was born after 277 eggs were used for SCNT, which created 29 viable embryos. Only three of these embryos survived until birth, and only one survived to adulthood.[14] As the procedure could not be automated, and had to be performed manually under a microscope, SCNT was very resource intensive. The biochemistry involved in reprogramming the differentiated somatic cell nucleus and activating the recipient egg was also far from being well understood. However, by 2014 researchers were reporting cloning success rates of seven to eight out of ten[15] and in 2016, a Korean Company Sooam Biotech was reported to be producing 500 cloned embryos per day.[16]

In SCNT, not all of the donor cell’s genetic information is transferred, as the donor cell’s mitochondria that contain their own mitochondrial DNA are left behind. The resulting hybrid cells retain those mitochondrial structures which originally belonged to the egg. As a consequence, clones such as Dolly that are born from SCNT are not perfect copies of the donor of the nucleus.

Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, cloning, or asexual propagation,[17] has been common practice in the horticultural world for hundreds of years.

The term clone is used in horticulture to refer to descendants of a single plant which were produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction.[18] As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana.[19] Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation.

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies naturally. Parts of an individual plant may become detached by fragmentation and grow on to become separate clonal individuals. A common example is in the vegetative reproduction of moss and liverwort gametophyte clones by means of gemmae. Some vascular plants e.g. dandelion and certain viviparous grasses also form seeds asexually, termed apomixis, resulting in clonal populations of genetically identical individuals.

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes,[20] fish (for example the hammerhead shark[21]), the Komodo dragon[21] and lizards. The growth and development occurs without fertilization by a male. In plants, parthenogenesis means the development of an embryo from an unfertilized egg cell, and is a component process of apomixis. In species that use the XY sex-determination system, the offspring will always be female. An example is the little fire ant (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments.

Artificial cloning of organisms may also be called reproductive cloning.

Hans Spemann, a German embryologist was awarded a Nobel Prize in Physiology or Medicine in 1935 for his discovery of the effect now known as embryonic induction, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs. In 1928 he and his student, Hilde Mangold, were the first to perform somatic-cell nuclear transfer using amphibian embryos one of the first steps towards cloning.[22]

Reproductive cloning generally uses “somatic cell nuclear transfer” (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg from which the nucleus has been removed, or to a cell from a blastocyst from which the nucleus has been removed.[23] If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this mitochondrial DNA is wholly from the cytoplasmic donor’s egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Artificial embryo splitting or embryo twinning, a technique that creates monozygotic twins from a single embryo, is not considered in the same fashion as other methods of cloning. During that procedure, a donor embryo is split in two distinct embryos, that can then be transferred via embryo transfer. It is optimally performed at the 6- to 8-cell stage, where it can be used as an expansion of IVF to increase the number of available embryos.[24] If both embryos are successful, it gives rise to monozygotic (identical) twins.

Dolly, a Finn-Dorset ewe, was the first mammal to have been successfully cloned from an adult somatic cell. Dolly was formed by taking a cell from the udder of her 6-year old biological mother.[25] Dolly’s embryo was created by taking the cell and inserting it into a sheep ovum. It took 434 attempts before an embryo was successful.[26] The embryo was then placed inside a female sheep that went through a normal pregnancy.[27] She was cloned at the Roslin Institute in Scotland by British scientists Sir Ian Wilmut and Keith Campbell and lived there from her birth in 1996 until her death in 2003 when she was six. She was born on 5 July 1996 but not announced to the world until 22 February 1997.[28] Her stuffed remains were placed at Edinburgh’s Royal Museum, part of the National Museums of Scotland.[29]

Dolly was publicly significant because the effort showed that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, can be reprogrammed to grow an entirely new organism. Before this demonstration, it had been shown by John Gurdon that nuclei from differentiated cells could give rise to an entire organism after transplantation into an enucleated egg.[30] However, this concept was not yet demonstrated in a mammalian system.

The first mammalian cloning (resulting in Dolly the sheep) had a success rate of 29 embryos per 277 fertilized eggs, which produced three lambs at birth, one of which lived. In a bovine experiment involving 70 cloned calves, one-third of the calves died young. The first successfully cloned horse, Prometea, took 814 attempts. Notably, although the first[clarification needed] clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the sheep had pathologies resembling accelerated aging. Scientists speculated that Dolly’s death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly’s early death due to respiratory infection was unrelated to deficiencies with the cloning process. This idea that the nuclei have not irreversibly aged was shown in 2013 to be true for mice.[31]

Dolly was named after performer Dolly Parton because the cells cloned to make her were from a mammary gland cell, and Parton is known for her ample cleavage.[32]

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Notable experiments include:

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissues. It does not refer to the natural conception and delivery of identical twins. The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass legislation regarding human cloning and its legality. As of right now, scientists have no intention of trying to clone people and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.[63]

Two commonly discussed types of theoretical human cloning are therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014[update]. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.[64]

There are a variety of ethical positions regarding the possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Advocates support development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants,[65] to avoid the need for immunosuppressive drugs,[64] and to stave off the effects of aging.[66] Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.[67]

Opponents of cloning have concerns that technology is not yet developed enough to be safe[68] and that it could be prone to abuse (leading to the generation of humans from whom organs and tissues would be harvested),[69][70] as well as concerns about how cloned individuals could integrate with families and with society at large.[71][72]

Religious groups are divided, with some opposing the technology as usurping “God’s place” and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.[73][74]

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die,[75][76] and while food from cloned animals has been approved by the US FDA,[77][78] its use is opposed by groups concerned about food safety.[79][80][81]

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream. Possible implications of this were dramatized in the 1984 novel Carnosaur and the 1990 novel Jurassic Park.[82][83] The best current cloning techniques have an average success rate of 9.4 percent[84] (and as high as 25 percent[31]) when working with familiar species such as mice,[note 1] while cloning wild animals is usually less than 1 percent successful.[87] Several tissue banks have come into existence, including the “Frozen Zoo” at the San Diego Zoo, to store frozen tissue from the world’s rarest and most endangered species.[82][88][89]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean ibex) were frozen in liquid nitrogen immediately after it died in 2000. Researchers are also considering cloning endangered species such as the giant panda and cheetah.

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the thylacine (Tasmanian tiger), at the time extinct for about 65 years, using polymerase chain reaction.[90] However, on 15 February 2005 the museum announced that it was stopping the project after tests showed the specimens’ DNA had been too badly degraded by the (ethanol) preservative. On 15 May 2005 it was announced that the thylacine project would be revived, with new participation from researchers in New South Wales and Victoria.

In 2003, for the first time, an extinct animal, the Pyrenean ibex mentioned above was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved frozen cell nucleus of the skin samples from 2001 and domestic goat egg-cells. The ibex died shortly after birth due to physical defects in its lungs.[91]

One of the most anticipated targets for cloning was once the woolly mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama, saying that they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.[92][93] It was noted, however that the result, if possible, would be an elephant-mammoth hybrid rather than a true mammoth.[94] Another problem is the survival of the reconstructed mammoth: ruminants rely on a symbiosis with specific microbiota in their stomachs for digestion.[94]

Scientists at the University of Newcastle and University of New South Wales announced in March 2013 that the very recently extinct gastric-brooding frog would be the subject of a cloning attempt to resurrect the species.[95]

Many such “de-extinction” projects are described in the Long Now Foundation’s Revive and Restore Project.[96]

After an eight-year project involving the use of a pioneering cloning technique, Japanese researchers created 25 generations of healthy cloned mice with normal lifespans, demonstrating that clones are not intrinsically shorter-lived than naturally born animals.[31][97] Other sources have noted that the offspring of clones tend to be healthier than the original clones and indistinguishable from animals produced naturally.[98]

Dolly the sheep was created from a six year old cell sample from a mammary gland. Because of this, she aged quicker than other naturally born animals because she was started from already aging cells. She died prematurely at six years old, not only from her age but from respiratory issues and severe arthritis.[citation needed][dubious discuss]

A detailed study released in 2016 and less detailed studies by others suggest that once cloned animals get past the first month or two of life they are generally healthy. However, early pregnancy loss and neonatal losses are still greater with cloning than natural conception or assisted reproduction (IVF). Current research is attempting to overcome these problems.[32]

Discussion of cloning in the popular media often presents the subject negatively. In an article in the 8 November 1993 article of Time, cloning was portrayed in a negative way, modifying Michelangelo’s Creation of Adam to depict Adam with five identical hands.[99] Newsweek’s 10 March 1997 issue also critiqued the ethics of human cloning, and included a graphic depicting identical babies in beakers.[100]

The concept of cloning, particularly human cloning, has featured a wide variety of science fiction works. An early fictional depiction of cloning is Bokanovsky’s Process which features in Aldous Huxley’s 1931 dystopian novel Brave New World. The process is applied to fertilized human eggs in vitro, causing them to split into identical genetic copies of the original.[101][102] Following renewed interest in cloning in the 1950s, the subject was explored further in works such as Poul Anderson’s 1953 story UN-Man, which describes a technology called “exogenesis”, and Gordon Rattray Taylor’s book The Biological Time Bomb, which popularised the term “cloning” in 1963.[103]

Cloning is a recurring theme in a number of contemporary science fiction films, ranging from action films such as Jurassic Park (1993), Alien Resurrection (1997), The 6th Day (2000), Resident Evil (2002), Star Wars: Episode II (2002) and The Island (2005), to comedies such as Woody Allen’s 1973 film Sleeper.[104]

The process of cloning is represented variously in fiction. Many works depict the artificial creation of humans by a method of growing cells from a tissue or DNA sample; the replication may be instantaneous, or take place through slow growth of human embryos in artificial wombs. In the long-running British television series Doctor Who, the Fourth Doctor and his companion Leela were cloned in a matter of seconds from DNA samples (“The Invisible Enemy”, 1977) and then in an apparent homage to the 1966 film Fantastic Voyage shrunk to microscopic size in order to enter the Doctor’s body to combat an alien virus. The clones in this story are short-lived, and can only survive a matter of minutes before they expire.[105] Science fiction films such as The Matrix and Star Wars: Episode II Attack of the Clones have featured scenes of human foetuses being cultured on an industrial scale in mechanical tanks.[106]

Cloning humans from body parts is also a common theme in science fiction. Cloning features strongly among the science fiction conventions parodied in Woody Allen’s Sleeper, the plot of which centres around an attempt to clone an assassinated dictator from his disembodied nose.[107] In the 2008 Doctor Who story “Journey’s End”, a duplicate version of the Tenth Doctor spontaneously grows from his severed hand, which had been cut off in a sword fight during an earlier episode.[108]

After the death of her beloved 14-year old Coton de Tulear named Samantha in late 2017, Barbra Streisand announced that she had cloned the dog, and was now “waiting for [the two cloned pups] to get older so [she] can see if they have [Samantha’s] brown eyes and her seriousness.” [109] The operation cost $50,000 through the pet cloning company ViaGen.

Science fiction has used cloning, most commonly and specifically human cloning, to raise the controversial questions of identity.[110][111] A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity, especially nature and nurture. The story, set in the near future, is structured around the conflict between a father (Salter) and his sons (Bernard 1, Bernard 2, and Michael Black) two of whom are clones of the first one. A Number was adapted by Caryl Churchill for television, in a co-production between the BBC and HBO Films.[112]

In 2012, a Japanese television series named “Bunshin” was created. The story’s main character, Mariko, is a woman studying child welfare in Hokkaido. She grew up always doubtful about the love from her mother, who looked nothing like her and who died nine years before. One day, she finds some of her mother’s belongings at a relative’s house, and heads to Tokyo to seek out the truth behind her birth. She later discovered that she was a clone.[113]

In the 2013 television series Orphan Black, cloning is used as a scientific study on the behavioral adaptation of the clones.[114] In a similar vein, the book The Double by Nobel Prize winner Jos Saramago explores the emotional experience of a man who discovers that he is a clone.[115]

Cloning has been used in fiction as a way of recreating historical figures. In the 1976 Ira Levin novel The Boys from Brazil and its 1978 film adaptation, Josef Mengele uses cloning to create copies of Adolf Hitler.[116]

In Michael Crichton’s 1990 novel Jurassic Park, which spawned a series of Jurassic Park feature films, a bioengineering company develops a technique to resurrect extinct species of dinosaurs by creating cloned creatures using DNA extracted from fossils. The cloned dinosaurs are used to populate the Jurassic Park wildlife park for the entertainment of visitors. The scheme goes disastrously wrong when the dinosaurs escape their enclosures. Despite being selectively cloned as females to prevent them from breeding, the dinosaurs develop the ability to reproduce through parthenogenesis.[117]

The use of cloning for military purposes has also been explored in several fictional works. In Doctor Who, an alien race of armour-clad, warlike beings called Sontarans was introduced in the 1973 serial “The Time Warrior”. Sontarans are depicted as squat, bald creatures who have been genetically engineered for combat. Their weak spot is a “probic vent”, a small socket at the back of their neck which is associated with the cloning process.[118] The concept of cloned soldiers being bred for combat was revisited in “The Doctor’s Daughter” (2008), when the Doctor’s DNA is used to create a female warrior called Jenny.[119]

The 1977 film Star Wars was set against the backdrop of a historical conflict called the Clone Wars. The events of this war were not fully explored until the prequel films Attack of the Clones (2002) and Revenge of the Sith (2005), which depict a space war waged by a massive army of heavily armoured clone troopers that leads to the foundation of the Galactic Empire. Cloned soldiers are “manufactured” on an industrial scale, genetically conditioned for obedience and combat effectiveness. It is also revealed that the popular character Boba Fett originated as a clone of Jango Fett, a mercenary who served as the genetic template for the clone troopers.[120][121]

A recurring sub-theme of cloning fiction is the use of clones as a supply of organs for transplantation. The 2005 Kazuo Ishiguro novel Never Let Me Go and the 2010 film adaption[122] are set in an alternate history in which cloned humans are created for the sole purpose of providing organ donations to naturally born humans, despite the fact that they are fully sentient and self-aware. The 2005 film The Island[123] revolves around a similar plot, with the exception that the clones are unaware of the reason for their existence.

The exploitation of human clones for dangerous and undesirable work was examined in the 2009 British science fiction film Moon.[124] In the futuristic novel Cloud Atlas and subsequent film, one of the story lines focuses on a genetically-engineered fabricant clone named Sonmi~451, one of millions raised in an artificial “wombtank,” destined to serve from birth. She is one of thousands created for manual and emotional labor; Sonmi herself works as a server in a restaurant. She later discovers that the sole source of food for clones, called ‘Soap’, is manufactured from the clones themselves.[125]

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Cloning – Wikipedia

Dolly (sheep) – Wikipedia

Dolly (5 July 1996 14 February 2003) was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer.

Dolly was cloned by Keith Campbell, Ian Wilmut and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland, and the biotechnology company PPL Therapeutics, based near Edinburgh. The funding for Dolly’s cloning was provided by PPL Therapeutics and the Ministry of Agriculture.[2] She was born on 5 July 1996 and died from a progressive lung disease five months before her seventh birthday (the disease was not considered related to her being a clone).[3] She has been called “the world’s most famous sheep” by sources including BBC News and Scientific American.[4][5]

The cell used as the donor for the cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. On Dolly’s name, Wilmut stated “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s”.[1]

Dolly was born on 5 July 1996 and had three mothers: one provided the egg, another the DNA, and a third carried the cloned embryo to term.[6] She was created using the technique of somatic cell nuclear transfer, where the cell nucleus from an adult cell is transferred into an unfertilized oocyte (developing egg cell) that has had its cell nucleus removed. The hybrid cell is then stimulated to divide by an electric shock, and when it develops into a blastocyst it is implanted in a surrogate mother.[7] Dolly was the first clone produced from a cell taken from an adult mammal.[8][9] The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting to an embryonic totipotent state, creating a cell that can then go on to develop into any part of an animal.[10] Dolly’s existence was announced to the public on 22 February 1997.[1] It gained much attention in the media. A commercial with Scottish scientists playing with sheep was aired on TV, and a special report in Time magazine featured Dolly the sheep.[2] Science featured Dolly as the breakthrough of the year. Even though Dolly was not the first animal cloned, she received media attention because she was the first cloned from an adult cell.[11]

Dolly lived her entire life at the Roslin Institute in Midlothian.[12] There she was bred with a Welsh Mountain ram and produced six lambs in total. Her first lamb, named Bonnie, was born in April 1998.[3] The next year Dolly produced twin lambs Sally and Rosie, and she gave birth to triplets Lucy, Darcy and Cotton in 2000.[13] In late 2001, at the age of four, Dolly developed arthritis and began to walk stiffly. This was treated with anti-inflammatory drugs.[14]

On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis.[15] A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years. A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte,[16] which is a fairly common disease of sheep and is caused by the retrovirus JSRV.[17] Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease.[15] Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons.

Some in the press speculated that a contributing factor to Dolly’s death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned.[18] One basis for this idea was the finding that Dolly’s telomeres were short, which is typically a result of the aging process.[19][20] The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.[18]

In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly. The first study to review the long-term health outcomes of cloning, the authors found no evidence of late-onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded “We could find no evidence, therefore, of a detrimental long-term effect of cloning by SCNT on the health of aged offspring among our cohort.”[21][22]

After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs,[23][24] deer,[25] horses[26] and bulls.[27] The attempt to clone argali (mountain sheep) did not produce viable embryos. The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring.[28] The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development.[29][30] Making cloned mammals was highly inefficient in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts. By 2014 Chinese scientists were reported to have 7080% success rates cloning pigs[24] and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day.[31] Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.[32]

Cloning may have uses in preserving endangered species and may become a viable tool for reviving extinct species.[33] In January 2009, scientists from the Centre of Food Technology and Research of Aragon, in northern Spain announced the cloning of the Pyrenean ibex, a form of wild mountain goat, which was officially declared extinct in 2000. Although the newborn ibex died shortly after birth due to physical defects in its lungs, it is the first time an extinct animal has been cloned, and may open doors for saving endangered and newly extinct species by resurrecting them from frozen tissue.[34][35]

In July 2016, four identical clones of Dolly (Daisy, Debbie, Dianna, and Denise) were alive and healthy at nine years old.[36][37]

Scientific American concluded in 2016 that the main legacy of Dolly the sheep has not been cloning of animals but in advances into stem cell research.[38] After Dolly, researchers realised that ordinary cells could be reprogrammed to induced pluripotent stem cells which can be grown into any tissue.[39]

The first successful cloning of a primate species using the same method for producing Dolly was reported in January 2018. Two identical clones of a macaque monkey, Zhong Zhong and Hua Hua, were created by researchers in China and were born in late 2017.[40][41][42][43]

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Dolly (sheep) – Wikipedia

Cloning Couture | Exploring the world of couture sewing

Thank you all for the many comments and compliments about this jacket. The finishing details are what sets French jackets apart and make this jacket unique. In addition to the custom trim, French jackets feature hand worked buttonholes, sleeves are set by hand, countless tiny stitches secure the lining and a metal chain inside the jacket allow it to drape perfectly when worn.

I think the sleeves are actually easier to set by hand and would be almost impossible to do by machine due to the unique construction methods. Although it would be easier to sew the armseye seam through all layers, I find joining only the outer fabrics together before hand basting the lining in place gives a softer, more fluid feel.

Heres an inside view of the armseye seam. Probably one if the messiest times in jacket construction. Yes, I used Pro Sheer Elegance Couture interfacing which was fused the jacket sections. Its extremely lightweight, flexible and doesnt change the drape of the tweed. Linton actually recommends doing this with their more loosely woven fabrics. Ive serged the edges of the tweed with a wide stitch but finished the seams of the lining with a narrow two thread stitch using fine thread. I like Gutermann Skala 360-U81, Invisafil by Wonderfil Threads, or 80 weight Maderia or Aurifil cotton. I use two strands of regular sewing thread, waxed and pressed, to set the sleeve. I sew the top part from the right side using tiny fell stitches and the underarm portion from the inside with a backstitch.

Notice at the point where the shoulder seam meets the sleeve seam, the seam allowances havent been caught but are allowed to float free. This allows the seam to press more smoothly and feels less rigid. Ive not included the sleeve lining; I feel I get a better result by joining only two layers of fabric at one time.

I create a sleeve head from cotton batting. Cut about 2.5 inches wide and 7 inches long. Fold along a long side about 1.5 inches from the edge, pull along the folded edge while steam pressing to curve. The folded edge is sewn along the armseye seam at the sleeve cap to provide additional shape and support.

Baste the sleeve lining just inside the armseye seam and trim away the excess fabric. Ive struggled with getting the lining over the sleeve cap evenly if the jacket is lying flat. Ive found it much easier to turn the jacket inside out and place on my dress form with a sleeve form attached. Now the jacket and sleeve are supported and its easier to manipulate the lining into position.

Pin along the seam and sew a line of tiny running stitches. Pull the gathering thread up to fit and tie a tailors knot at each end. Trim off the excess and the fabric will fold under easily along the gathering line. I set the sleeve cap first, baste, then remove the jacket from the form. The lining at the underarm is brought up and around the seam allowances.

I had originally planned for front buttons, but decided I liked the look of trim without buttons, and considered a front zipper. Botani Trimming in NYC makes custom zippers and does mail order. You select the zipper tooth size, length, color and pull. The zipper arrives in a few days and they even had chain for the hem. Finding the right zipper in a local shop would have been impossible. Just as an interesting side note, Botani sells Lampo zippers. They are made in Italy and the same brand that Chanel uses!

How to deal with the lining? I could have folded it back past the zipper teeth and stitched into place but that left the zipper teeth exposed on the inside of the jacket. In true couture fashion, I wanted to cover up that metal. Placing a length of ribbon inside the fold beefed up the edge of the silk charmeuse so it would be less likely to catch on the zipper pull. This was one time when that rigid, slightly raised edge on polyester ribbon was useful. Now zipper teeth are concealed, both inside and out.

The dreaded buttonholes next. Machine made buttonholes lack the couture finish this jacket needed. Ive experimented with countless ways to improve my hand worked version. Ive found that sewing around the buttonhole before cutting, especially in a fabric such as this, helps tremendously to keep the layers together. Marking and sewing this manually on the machine requires much twisting and turning of the fabric so I searched for an easier way. My machine sews a square buttonhole using a straight stitch so I tried that, stitching around the buttonhole twice, once at a narrow width and again a little wider.

Looks OK but I didnt like the thread buildup at the beginning and end (impossible to stop the machine from knotting the threads) plus I really wanted a keyhole buttonhole.

My Bernina does embroidery and I have digitizing software so I created a template for the buttonholes. I hooped a square of heavy muslin, stitched out the placement lines for the sleeve; then cut out a window so the stitching wouldnt get caught on the muslin. The sleeve was pinned onto the muslin. Working wrong side up worked better. The sleeve was easier to place and keep the fabric clear of the stitching area, plus the embroidery foot wouldnt get snagged on the loose fibers of the tweed. The embroidery software will insert buttonholes automatically, but I wasnt able to adjust the shape and stitch length satisfactorily. I also wasnt able to do the double rows. Mirror the image for the other sleeve and remember to cut another window so your muslin doesnt get stitched to the fabric.

There are several YouTube videos showing hand worked buttonholes if you need a review. I worked under a magnifying light and tried to keep the buttonhole stitches just inside the second row of machine stitching. It provided a nice guide for straight, narrow stitches. Buttonholes arent easy and most people say they need to work a hundreds before somewhat mastering the art. Im always trying to make mine better but these arent bad.

Ive been inspired by the photos of sheath dresses with matching jackets ( Helen Haugheys class looked wonderful) so thats next in the sewing lineup. Thanks for reading.

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Cloning Couture | Exploring the world of couture sewing

Cloning – Wikipedia

Cloning is the process of producing genetically identical individuals of an organism either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments (molecular cloning). Beyond biology, the term refers to the production of multiple copies of digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word kln, “twig”, referring to the process whereby a new plant can be created from a twig. In botany, the term lusus was traditionally used.[1] In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a “long o” instead of a “short o”.[2][3] Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Cloning is a natural form of reproduction that has allowed life forms to spread for hundreds of millions of years. It is the reproduction method used by plants, fungi, and bacteria, and is also the way that clonal colonies reproduce themselves.[4][5] Examples of these organisms include blueberry plants, hazel trees, the Pando trees,[6][7] the Kentucky coffeetree, Myricas, and the American sweetgum.

Molecular cloning refers to the process of making multiple molecules. Cloning is commonly used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. To amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. However, a number of other features are needed, and a variety of specialised cloning vectors (small piece of DNA into which a foreign DNA fragment can be inserted) exist that allow protein production, affinity tagging, single stranded RNA or DNA production and a host of other molecular biology tools.

Cloning of any DNA fragment essentially involves four steps[8]

Although these steps are invariable among cloning procedures a number of alternative routes can be selected; these are summarized as a cloning strategy.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector (piece of DNA). The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation, optical injection and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. Additionally, the cloning vectors may contain colour selection markers, which provide blue/white screening (alpha-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies must be required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing.

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders).[9] In this technique a single-cell suspension of cells that have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies, each arising from a single and potentially clonal distinct cell. At an early growth stage when colonies consist of only a few cells, sterile polystyrene rings (cloning rings), which have been dipped in grease, are placed over an individual colony and a small amount of trypsin is added. Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Somatic-cell nuclear transfer, known as SCNT, can also be used to create embryos for research or therapeutic purposes. The most likely purpose for this is to produce embryos for use in stem cell research. This process is also called “research cloning” or “therapeutic cloning.” The goal is not to create cloned human beings (called “reproductive cloning”), but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source.[10]

Therapeutic cloning is achieved by creating embryonic stem cells in the hopes of treating diseases such as diabetes and Alzheimer’s. The process begins by removing the nucleus (containing the DNA) from an egg cell and inserting a nucleus from the adult cell to be cloned.[11] In the case of someone with Alzheimer’s disease, the nucleus from a skin cell of that patient is placed into an empty egg. The reprogrammed cell begins to develop into an embryo because the egg reacts with the transferred nucleus. The embryo will become genetically identical to the patient.[11] The embryo will then form a blastocyst which has the potential to form/become any cell in the body.[12]

The reason why SCNT is used for cloning is because somatic cells can be easily acquired and cultured in the lab. This process can either add or delete specific genomes of farm animals. A key point to remember is that cloning is achieved when the oocyte maintains its normal functions and instead of using sperm and egg genomes to replicate, the oocyte is inserted into the donor’s somatic cell nucleus.[13] The oocyte will react on the somatic cell nucleus, the same way it would on sperm cells.[13]

The process of cloning a particular farm animal using SCNT is relatively the same for all animals. The first step is to collect the somatic cells from the animal that will be cloned. The somatic cells could be used immediately or stored in the laboratory for later use.[13] The hardest part of SCNT is removing maternal DNA from an oocyte at metaphase II. Once this has been done, the somatic nucleus can be inserted into an egg cytoplasm.[13] This creates a one-cell embryo. The grouped somatic cell and egg cytoplasm are then introduced to an electrical current.[13] This energy will hopefully allow the cloned embryo to begin development. The successfully developed embryos are then placed in surrogate recipients, such as a cow or sheep in the case of farm animals.[13]

SCNT is seen as a good method for producing agriculture animals for food consumption. It successfully cloned sheep, cattle, goats, and pigs. Another benefit is SCNT is seen as a solution to clone endangered species that are on the verge of going extinct.[13] However, stresses placed on both the egg cell and the introduced nucleus can be enormous, which led to a high loss in resulting cells in early research. For example, the cloned sheep Dolly was born after 277 eggs were used for SCNT, which created 29 viable embryos. Only three of these embryos survived until birth, and only one survived to adulthood.[14] As the procedure could not be automated, and had to be performed manually under a microscope, SCNT was very resource intensive. The biochemistry involved in reprogramming the differentiated somatic cell nucleus and activating the recipient egg was also far from being well understood. However, by 2014 researchers were reporting cloning success rates of seven to eight out of ten[15] and in 2016, a Korean Company Sooam Biotech was reported to be producing 500 cloned embryos per day.[16]

In SCNT, not all of the donor cell’s genetic information is transferred, as the donor cell’s mitochondria that contain their own mitochondrial DNA are left behind. The resulting hybrid cells retain those mitochondrial structures which originally belonged to the egg. As a consequence, clones such as Dolly that are born from SCNT are not perfect copies of the donor of the nucleus.

Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, cloning, or asexual propagation,[17] has been common practice in the horticultural world for hundreds of years.

The term clone is used in horticulture to refer to descendants of a single plant which were produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction.[18] As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana.[19] Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation.

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies naturally. Parts of an individual plant may become detached by fragmentation and grow on to become separate clonal individuals. A common example is in the vegetative reproduction of moss and liverwort gametophyte clones by means of gemmae. Some vascular plants e.g. dandelion and certain viviparous grasses also form seeds asexually, termed apomixis, resulting in clonal populations of genetically identical individuals.

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes,[20] fish (for example the hammerhead shark[21]), the Komodo dragon[21] and lizards. The growth and development occurs without fertilization by a male. In plants, parthenogenesis means the development of an embryo from an unfertilized egg cell, and is a component process of apomixis. In species that use the XY sex-determination system, the offspring will always be female. An example is the little fire ant (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments.

Artificial cloning of organisms may also be called reproductive cloning.

Hans Spemann, a German embryologist was awarded a Nobel Prize in Physiology or Medicine in 1935 for his discovery of the effect now known as embryonic induction, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs. In 1928 he and his student, Hilde Mangold, were the first to perform somatic-cell nuclear transfer using amphibian embryos one of the first steps towards cloning.[22]

Reproductive cloning generally uses “somatic cell nuclear transfer” (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg from which the nucleus has been removed, or to a cell from a blastocyst from which the nucleus has been removed.[23] If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this mitochondrial DNA is wholly from the cytoplasmic donor’s egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Artificial embryo splitting or embryo twinning, a technique that creates monozygotic twins from a single embryo, is not considered in the same fashion as other methods of cloning. During that procedure, a donor embryo is split in two distinct embryos, that can then be transferred via embryo transfer. It is optimally performed at the 6- to 8-cell stage, where it can be used as an expansion of IVF to increase the number of available embryos.[24] If both embryos are successful, it gives rise to monozygotic (identical) twins.

Dolly, a Finn-Dorset ewe, was the first mammal to have been successfully cloned from an adult somatic cell. Dolly was formed by taking a cell from the udder of her 6-year old biological mother.[25] Dolly’s embryo was created by taking the cell and inserting it into a sheep ovum. It took 434 attempts before an embryo was successful.[26] The embryo was then placed inside a female sheep that went through a normal pregnancy.[27] She was cloned at the Roslin Institute in Scotland by British scientists Sir Ian Wilmut and Keith Campbell and lived there from her birth in 1996 until her death in 2003 when she was six. She was born on 5 July 1996 but not announced to the world until 22 February 1997.[28] Her stuffed remains were placed at Edinburgh’s Royal Museum, part of the National Museums of Scotland.[29]

Dolly was publicly significant because the effort showed that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, can be reprogrammed to grow an entirely new organism. Before this demonstration, it had been shown by John Gurdon that nuclei from differentiated cells could give rise to an entire organism after transplantation into an enucleated egg.[30] However, this concept was not yet demonstrated in a mammalian system.

The first mammalian cloning (resulting in Dolly the sheep) had a success rate of 29 embryos per 277 fertilized eggs, which produced three lambs at birth, one of which lived. In a bovine experiment involving 70 cloned calves, one-third of the calves died young. The first successfully cloned horse, Prometea, took 814 attempts. Notably, although the first[clarification needed] clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the sheep had pathologies resembling accelerated aging. Scientists speculated that Dolly’s death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly’s early death due to respiratory infection was unrelated to deficiencies with the cloning process. This idea that the nuclei have not irreversibly aged was shown in 2013 to be true for mice.[31]

Dolly was named after performer Dolly Parton because the cells cloned to make her were from a mammary gland cell, and Parton is known for her ample cleavage.[32]

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Notable experiments include:

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissues. It does not refer to the natural conception and delivery of identical twins. The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass legislation regarding human cloning and its legality. As of right now, scientists have no intention of trying to clone people and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.[63]

Two commonly discussed types of theoretical human cloning are therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014[update]. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.[64]

There are a variety of ethical positions regarding the possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Advocates support development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants,[65] to avoid the need for immunosuppressive drugs,[64] and to stave off the effects of aging.[66] Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.[67]

Opponents of cloning have concerns that technology is not yet developed enough to be safe[68] and that it could be prone to abuse (leading to the generation of humans from whom organs and tissues would be harvested),[69][70] as well as concerns about how cloned individuals could integrate with families and with society at large.[71][72]

Religious groups are divided, with some opposing the technology as usurping “God’s place” and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.[73][74]

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die,[75][76] and while food from cloned animals has been approved by the US FDA,[77][78] its use is opposed by groups concerned about food safety.[79][80][81]

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream. Possible implications of this were dramatized in the 1984 novel Carnosaur and the 1990 novel Jurassic Park.[82][83] The best current cloning techniques have an average success rate of 9.4 percent[84] (and as high as 25 percent[31]) when working with familiar species such as mice,[note 1] while cloning wild animals is usually less than 1 percent successful.[87] Several tissue banks have come into existence, including the “Frozen Zoo” at the San Diego Zoo, to store frozen tissue from the world’s rarest and most endangered species.[82][88][89]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean ibex) were frozen in liquid nitrogen immediately after it died in 2000. Researchers are also considering cloning endangered species such as the giant panda and cheetah.

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the thylacine (Tasmanian tiger), at the time extinct for about 65 years, using polymerase chain reaction.[90] However, on 15 February 2005 the museum announced that it was stopping the project after tests showed the specimens’ DNA had been too badly degraded by the (ethanol) preservative. On 15 May 2005 it was announced that the thylacine project would be revived, with new participation from researchers in New South Wales and Victoria.

In 2003, for the first time, an extinct animal, the Pyrenean ibex mentioned above was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved frozen cell nucleus of the skin samples from 2001 and domestic goat egg-cells. The ibex died shortly after birth due to physical defects in its lungs.[91]

One of the most anticipated targets for cloning was once the woolly mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama, saying that they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.[92][93] It was noted, however that the result, if possible, would be an elephant-mammoth hybrid rather than a true mammoth.[94] Another problem is the survival of the reconstructed mammoth: ruminants rely on a symbiosis with specific microbiota in their stomachs for digestion.[94]

Scientists at the University of Newcastle and University of New South Wales announced in March 2013 that the very recently extinct gastric-brooding frog would be the subject of a cloning attempt to resurrect the species.[95]

Many such “de-extinction” projects are described in the Long Now Foundation’s Revive and Restore Project.[96]

After an eight-year project involving the use of a pioneering cloning technique, Japanese researchers created 25 generations of healthy cloned mice with normal lifespans, demonstrating that clones are not intrinsically shorter-lived than naturally born animals.[31][97] Other sources have noted that the offspring of clones tend to be healthier than the original clones and indistinguishable from animals produced naturally.[98]

Dolly the sheep was created from a six year old cell sample from a mammary gland. Because of this, she aged quicker than other naturally born animals because she was started from already aging cells. She died prematurely at six years old, not only from her age but from respiratory issues and severe arthritis.[citation needed][dubious discuss]

A detailed study released in 2016 and less detailed studies by others suggest that once cloned animals get past the first month or two of life they are generally healthy. However, early pregnancy loss and neonatal losses are still greater with cloning than natural conception or assisted reproduction (IVF). Current research is attempting to overcome these problems.[32]

Discussion of cloning in the popular media often presents the subject negatively. In an article in the 8 November 1993 article of Time, cloning was portrayed in a negative way, modifying Michelangelo’s Creation of Adam to depict Adam with five identical hands.[99] Newsweek’s 10 March 1997 issue also critiqued the ethics of human cloning, and included a graphic depicting identical babies in beakers.[100]

The concept of cloning, particularly human cloning, has featured a wide variety of science fiction works. An early fictional depiction of cloning is Bokanovsky’s Process which features in Aldous Huxley’s 1931 dystopian novel Brave New World. The process is applied to fertilized human eggs in vitro, causing them to split into identical genetic copies of the original.[101][102] Following renewed interest in cloning in the 1950s, the subject was explored further in works such as Poul Anderson’s 1953 story UN-Man, which describes a technology called “exogenesis”, and Gordon Rattray Taylor’s book The Biological Time Bomb, which popularised the term “cloning” in 1963.[103]

Cloning is a recurring theme in a number of contemporary science fiction films, ranging from action films such as Jurassic Park (1993), Alien Resurrection (1997), The 6th Day (2000), Resident Evil (2002), Star Wars: Episode II (2002) and The Island (2005), to comedies such as Woody Allen’s 1973 film Sleeper.[104]

The process of cloning is represented variously in fiction. Many works depict the artificial creation of humans by a method of growing cells from a tissue or DNA sample; the replication may be instantaneous, or take place through slow growth of human embryos in artificial wombs. In the long-running British television series Doctor Who, the Fourth Doctor and his companion Leela were cloned in a matter of seconds from DNA samples (“The Invisible Enemy”, 1977) and then in an apparent homage to the 1966 film Fantastic Voyage shrunk to microscopic size in order to enter the Doctor’s body to combat an alien virus. The clones in this story are short-lived, and can only survive a matter of minutes before they expire.[105] Science fiction films such as The Matrix and Star Wars: Episode II Attack of the Clones have featured scenes of human foetuses being cultured on an industrial scale in mechanical tanks.[106]

Cloning humans from body parts is also a common theme in science fiction. Cloning features strongly among the science fiction conventions parodied in Woody Allen’s Sleeper, the plot of which centres around an attempt to clone an assassinated dictator from his disembodied nose.[107] In the 2008 Doctor Who story “Journey’s End”, a duplicate version of the Tenth Doctor spontaneously grows from his severed hand, which had been cut off in a sword fight during an earlier episode.[108]

After the death of her beloved 14-year old Coton de Tulear named Samantha in late 2017, Barbra Streisand announced that she had cloned the dog, and was now “waiting for [the two cloned pups] to get older so [she] can see if they have [Samantha’s] brown eyes and her seriousness.” [109] The operation cost $50,000 through the pet cloning company ViaGen.

Science fiction has used cloning, most commonly and specifically human cloning, to raise the controversial questions of identity.[110][111] A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity, especially nature and nurture. The story, set in the near future, is structured around the conflict between a father (Salter) and his sons (Bernard 1, Bernard 2, and Michael Black) two of whom are clones of the first one. A Number was adapted by Caryl Churchill for television, in a co-production between the BBC and HBO Films.[112]

In 2012, a Japanese television series named “Bunshin” was created. The story’s main character, Mariko, is a woman studying child welfare in Hokkaido. She grew up always doubtful about the love from her mother, who looked nothing like her and who died nine years before. One day, she finds some of her mother’s belongings at a relative’s house, and heads to Tokyo to seek out the truth behind her birth. She later discovered that she was a clone.[113]

In the 2013 television series Orphan Black, cloning is used as a scientific study on the behavioral adaptation of the clones.[114] In a similar vein, the book The Double by Nobel Prize winner Jos Saramago explores the emotional experience of a man who discovers that he is a clone.[115]

Cloning has been used in fiction as a way of recreating historical figures. In the 1976 Ira Levin novel The Boys from Brazil and its 1978 film adaptation, Josef Mengele uses cloning to create copies of Adolf Hitler.[116]

In Michael Crichton’s 1990 novel Jurassic Park, which spawned a series of Jurassic Park feature films, a bioengineering company develops a technique to resurrect extinct species of dinosaurs by creating cloned creatures using DNA extracted from fossils. The cloned dinosaurs are used to populate the Jurassic Park wildlife park for the entertainment of visitors. The scheme goes disastrously wrong when the dinosaurs escape their enclosures. Despite being selectively cloned as females to prevent them from breeding, the dinosaurs develop the ability to reproduce through parthenogenesis.[117]

The use of cloning for military purposes has also been explored in several fictional works. In Doctor Who, an alien race of armour-clad, warlike beings called Sontarans was introduced in the 1973 serial “The Time Warrior”. Sontarans are depicted as squat, bald creatures who have been genetically engineered for combat. Their weak spot is a “probic vent”, a small socket at the back of their neck which is associated with the cloning process.[118] The concept of cloned soldiers being bred for combat was revisited in “The Doctor’s Daughter” (2008), when the Doctor’s DNA is used to create a female warrior called Jenny.[119]

The 1977 film Star Wars was set against the backdrop of a historical conflict called the Clone Wars. The events of this war were not fully explored until the prequel films Attack of the Clones (2002) and Revenge of the Sith (2005), which depict a space war waged by a massive army of heavily armoured clone troopers that leads to the foundation of the Galactic Empire. Cloned soldiers are “manufactured” on an industrial scale, genetically conditioned for obedience and combat effectiveness. It is also revealed that the popular character Boba Fett originated as a clone of Jango Fett, a mercenary who served as the genetic template for the clone troopers.[120][121]

A recurring sub-theme of cloning fiction is the use of clones as a supply of organs for transplantation. The 2005 Kazuo Ishiguro novel Never Let Me Go and the 2010 film adaption[122] are set in an alternate history in which cloned humans are created for the sole purpose of providing organ donations to naturally born humans, despite the fact that they are fully sentient and self-aware. The 2005 film The Island[123] revolves around a similar plot, with the exception that the clones are unaware of the reason for their existence.

The exploitation of human clones for dangerous and undesirable work was examined in the 2009 British science fiction film Moon.[124] In the futuristic novel Cloud Atlas and subsequent film, one of the story lines focuses on a genetically-engineered fabricant clone named Sonmi~451, one of millions raised in an artificial “wombtank,” destined to serve from birth. She is one of thousands created for manual and emotional labor; Sonmi herself works as a server in a restaurant. She later discovers that the sole source of food for clones, called ‘Soap’, is manufactured from the clones themselves.[125]

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Cloning – Wikipedia

Cloning Couture | Exploring the world of couture sewing

Thank you all for the many comments and compliments about this jacket. The finishing details are what sets French jackets apart and make this jacket unique. In addition to the custom trim, French jackets feature hand worked buttonholes, sleeves are set by hand, countless tiny stitches secure the lining and a metal chain inside the jacket allow it to drape perfectly when worn.

I think the sleeves are actually easier to set by hand and would be almost impossible to do by machine due to the unique construction methods. Although it would be easier to sew the armseye seam through all layers, I find joining only the outer fabrics together before hand basting the lining in place gives a softer, more fluid feel.

Heres an inside view of the armseye seam. Probably one if the messiest times in jacket construction. Yes, I used Pro Sheer Elegance Couture interfacing which was fused the jacket sections. Its extremely lightweight, flexible and doesnt change the drape of the tweed. Linton actually recommends doing this with their more loosely woven fabrics. Ive serged the edges of the tweed with a wide stitch but finished the seams of the lining with a narrow two thread stitch using fine thread. I like Gutermann Skala 360-U81, Invisafil by Wonderfil Threads, or 80 weight Maderia or Aurifil cotton. I use two strands of regular sewing thread, waxed and pressed, to set the sleeve. I sew the top part from the right side using tiny fell stitches and the underarm portion from the inside with a backstitch.

Notice at the point where the shoulder seam meets the sleeve seam, the seam allowances havent been caught but are allowed to float free. This allows the seam to press more smoothly and feels less rigid. Ive not included the sleeve lining; I feel I get a better result by joining only two layers of fabric at one time.

I create a sleeve head from cotton batting. Cut about 2.5 inches wide and 7 inches long. Fold along a long side about 1.5 inches from the edge, pull along the folded edge while steam pressing to curve. The folded edge is sewn along the armseye seam at the sleeve cap to provide additional shape and support.

Baste the sleeve lining just inside the armseye seam and trim away the excess fabric. Ive struggled with getting the lining over the sleeve cap evenly if the jacket is lying flat. Ive found it much easier to turn the jacket inside out and place on my dress form with a sleeve form attached. Now the jacket and sleeve are supported and its easier to manipulate the lining into position.

Pin along the seam and sew a line of tiny running stitches. Pull the gathering thread up to fit and tie a tailors knot at each end. Trim off the excess and the fabric will fold under easily along the gathering line. I set the sleeve cap first, baste, then remove the jacket from the form. The lining at the underarm is brought up and around the seam allowances.

I had originally planned for front buttons, but decided I liked the look of trim without buttons, and considered a front zipper. Botani Trimming in NYC makes custom zippers and does mail order. You select the zipper tooth size, length, color and pull. The zipper arrives in a few days and they even had chain for the hem. Finding the right zipper in a local shop would have been impossible. Just as an interesting side note, Botani sells Lampo zippers. They are made in Italy and the same brand that Chanel uses!

How to deal with the lining? I could have folded it back past the zipper teeth and stitched into place but that left the zipper teeth exposed on the inside of the jacket. In true couture fashion, I wanted to cover up that metal. Placing a length of ribbon inside the fold beefed up the edge of the silk charmeuse so it would be less likely to catch on the zipper pull. This was one time when that rigid, slightly raised edge on polyester ribbon was useful. Now zipper teeth are concealed, both inside and out.

The dreaded buttonholes next. Machine made buttonholes lack the couture finish this jacket needed. Ive experimented with countless ways to improve my hand worked version. Ive found that sewing around the buttonhole before cutting, especially in a fabric such as this, helps tremendously to keep the layers together. Marking and sewing this manually on the machine requires much twisting and turning of the fabric so I searched for an easier way. My machine sews a square buttonhole using a straight stitch so I tried that, stitching around the buttonhole twice, once at a narrow width and again a little wider.

Looks OK but I didnt like the thread buildup at the beginning and end (impossible to stop the machine from knotting the threads) plus I really wanted a keyhole buttonhole.

My Bernina does embroidery and I have digitizing software so I created a template for the buttonholes. I hooped a square of heavy muslin, stitched out the placement lines for the sleeve; then cut out a window so the stitching wouldnt get caught on the muslin. The sleeve was pinned onto the muslin. Working wrong side up worked better. The sleeve was easier to place and keep the fabric clear of the stitching area, plus the embroidery foot wouldnt get snagged on the loose fibers of the tweed. The embroidery software will insert buttonholes automatically, but I wasnt able to adjust the shape and stitch length satisfactorily. I also wasnt able to do the double rows. Mirror the image for the other sleeve and remember to cut another window so your muslin doesnt get stitched to the fabric.

There are several YouTube videos showing hand worked buttonholes if you need a review. I worked under a magnifying light and tried to keep the buttonhole stitches just inside the second row of machine stitching. It provided a nice guide for straight, narrow stitches. Buttonholes arent easy and most people say they need to work a hundreds before somewhat mastering the art. Im always trying to make mine better but these arent bad.

Ive been inspired by the photos of sheath dresses with matching jackets ( Helen Haugheys class looked wonderful) so thats next in the sewing lineup. Thanks for reading.

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Cloning Couture | Exploring the world of couture sewing

Free cloning Essays and Papers – 123helpme.com

– The Pleistocene epoch spanned from 1.8 million years ago to 10,000 years ago [1]. Many genera and even species such as conifers, mosses, flowering plants, insects, mollusks, birds, and mammals from that era still survive today [1]. Others, such as the long-horned bison, saber-toothed cats, giant ground sloths, and the mammoth did not survive [1]. The woolly mammoth was commonly found during the last ice age [2]. These animals were similar in size to todays elephants but were adapted for living in the extremely cold conditions typical of an ice age [2]…. [tags: mammoths, ice age, extinct, climate]

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Dolly (sheep) – Wikipedia

Dolly (5 July 1996 14 February 2003) was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer.

Dolly was cloned by Keith Campbell, Ian Wilmut and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland, and the biotechnology company PPL Therapeutics, based near Edinburgh. The funding for Dolly’s cloning was provided by PPL Therapeutics and the Ministry of Agriculture.[2] She was born on 5 July 1996 and died from a progressive lung disease five months before her seventh birthday (the disease was not considered related to her being a clone).[3] She has been called “the world’s most famous sheep” by sources including BBC News and Scientific American.[4][5]

The cell used as the donor for the cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. On Dolly’s name, Wilmut stated “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s”.[1]

Dolly was born on 5 July 1996 and had three mothers: one provided the egg, another the DNA, and a third carried the cloned embryo to term.[6] She was created using the technique of somatic cell nuclear transfer, where the cell nucleus from an adult cell is transferred into an unfertilized oocyte (developing egg cell) that has had its cell nucleus removed. The hybrid cell is then stimulated to divide by an electric shock, and when it develops into a blastocyst it is implanted in a surrogate mother.[7] Dolly was the first clone produced from a cell taken from an adult mammal.[8][9] The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting to an embryonic totipotent state, creating a cell that can then go on to develop into any part of an animal.[10] Dolly’s existence was announced to the public on 22 February 1997.[1] It gained much attention in the media. A commercial with Scottish scientists playing with sheep was aired on TV, and a special report in Time magazine featured Dolly the sheep.[2] Science featured Dolly as the breakthrough of the year. Even though Dolly was not the first animal cloned, she received media attention because she was the first cloned from an adult cell.[11]

Dolly lived her entire life at the Roslin Institute in Midlothian.[12] There she was bred with a Welsh Mountain ram and produced six lambs in total. Her first lamb, named Bonnie, was born in April 1998.[3] The next year Dolly produced twin lambs Sally and Rosie, and she gave birth to triplets Lucy, Darcy and Cotton in 2000.[13] In late 2001, at the age of four, Dolly developed arthritis and began to walk stiffly. This was treated with anti-inflammatory drugs.[14]

On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis.[15] A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years. A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte,[16] which is a fairly common disease of sheep and is caused by the retrovirus JSRV.[17] Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease.[15] Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons.

Some in the press speculated that a contributing factor to Dolly’s death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned.[18] One basis for this idea was the finding that Dolly’s telomeres were short, which is typically a result of the aging process.[19][20] The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.[18]

In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly. The first study to review the long-term health outcomes of cloning, the authors found no evidence of late-onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded “We could find no evidence, therefore, of a detrimental long-term effect of cloning by SCNT on the health of aged offspring among our cohort.”[21][22]

After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs,[23][24] deer,[25] horses[26] and bulls.[27] The attempt to clone argali (mountain sheep) did not produce viable embryos. The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring.[28] The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development.[29][30] Making cloned mammals was highly inefficient in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts. By 2014 Chinese scientists were reported to have 7080% success rates cloning pigs[24] and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day.[31] Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.[32]

Cloning may have uses in preserving endangered species and may become a viable tool for reviving extinct species.[33] In January 2009, scientists from the Centre of Food Technology and Research of Aragon, in northern Spain announced the cloning of the Pyrenean ibex, a form of wild mountain goat, which was officially declared extinct in 2000. Although the newborn ibex died shortly after birth due to physical defects in its lungs, it is the first time an extinct animal has been cloned, and may open doors for saving endangered and newly extinct species by resurrecting them from frozen tissue.[34][35]

In July 2016, four identical clones of Dolly (Daisy, Debbie, Dianna, and Denise) were alive and healthy at nine years old.[36][37]

Scientific American concluded in 2016 that the main legacy of Dolly the sheep has not been cloning of animals but in advances into stem cell research.[38] After Dolly, researchers realised that ordinary cells could be reprogrammed to induced pluripotent stem cells which can be grown into any tissue.[39]

The first successful cloning of a primate species using the same method for producing Dolly was reported in January 2018. Two identical clones of a macaque monkey, Zhong Zhong and Hua Hua, were created by researchers in China and were born in late 2017.[40][41][42][43]

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Dolly (sheep) – Wikipedia

Cloning – Wikipedia

Cloning is the process of producing genetically identical individuals of an organism either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments (molecular cloning). Beyond biology, the term refers to the production of multiple copies of digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word kln, “twig”, referring to the process whereby a new plant can be created from a twig. In botany, the term lusus was traditionally used.[1] In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a “long o” instead of a “short o”.[2][3] Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Cloning is a natural form of reproduction that has allowed life forms to spread for hundreds of millions of years. It is the reproduction method used by plants, fungi, and bacteria, and is also the way that clonal colonies reproduce themselves.[4][5] Examples of these organisms include blueberry plants, hazel trees, the Pando trees,[6][7] the Kentucky coffeetree, Myricas, and the American sweetgum.

Molecular cloning refers to the process of making multiple molecules. Cloning is commonly used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. To amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. However, a number of other features are needed, and a variety of specialised cloning vectors (small piece of DNA into which a foreign DNA fragment can be inserted) exist that allow protein production, affinity tagging, single stranded RNA or DNA production and a host of other molecular biology tools.

Cloning of any DNA fragment essentially involves four steps[8]

Although these steps are invariable among cloning procedures a number of alternative routes can be selected; these are summarized as a cloning strategy.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector (piece of DNA). The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation, optical injection and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. Additionally, the cloning vectors may contain colour selection markers, which provide blue/white screening (alpha-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies must be required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing.

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders).[9] In this technique a single-cell suspension of cells that have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies, each arising from a single and potentially clonal distinct cell. At an early growth stage when colonies consist of only a few cells, sterile polystyrene rings (cloning rings), which have been dipped in grease, are placed over an individual colony and a small amount of trypsin is added. Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Somatic-cell nuclear transfer, known as SCNT, can also be used to create embryos for research or therapeutic purposes. The most likely purpose for this is to produce embryos for use in stem cell research. This process is also called “research cloning” or “therapeutic cloning.” The goal is not to create cloned human beings (called “reproductive cloning”), but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source.[10]

Therapeutic cloning is achieved by creating embryonic stem cells in the hopes of treating diseases such as diabetes and Alzheimer’s. The process begins by removing the nucleus (containing the DNA) from an egg cell and inserting a nucleus from the adult cell to be cloned.[11] In the case of someone with Alzheimer’s disease, the nucleus from a skin cell of that patient is placed into an empty egg. The reprogrammed cell begins to develop into an embryo because the egg reacts with the transferred nucleus. The embryo will become genetically identical to the patient.[11] The embryo will then form a blastocyst which has the potential to form/become any cell in the body.[12]

The reason why SCNT is used for cloning is because somatic cells can be easily acquired and cultured in the lab. This process can either add or delete specific genomes of farm animals. A key point to remember is that cloning is achieved when the oocyte maintains its normal functions and instead of using sperm and egg genomes to replicate, the oocyte is inserted into the donor’s somatic cell nucleus.[13] The oocyte will react on the somatic cell nucleus, the same way it would on sperm cells.[13]

The process of cloning a particular farm animal using SCNT is relatively the same for all animals. The first step is to collect the somatic cells from the animal that will be cloned. The somatic cells could be used immediately or stored in the laboratory for later use.[13] The hardest part of SCNT is removing maternal DNA from an oocyte at metaphase II. Once this has been done, the somatic nucleus can be inserted into an egg cytoplasm.[13] This creates a one-cell embryo. The grouped somatic cell and egg cytoplasm are then introduced to an electrical current.[13] This energy will hopefully allow the cloned embryo to begin development. The successfully developed embryos are then placed in surrogate recipients, such as a cow or sheep in the case of farm animals.[13]

SCNT is seen as a good method for producing agriculture animals for food consumption. It successfully cloned sheep, cattle, goats, and pigs. Another benefit is SCNT is seen as a solution to clone endangered species that are on the verge of going extinct.[13] However, stresses placed on both the egg cell and the introduced nucleus can be enormous, which led to a high loss in resulting cells in early research. For example, the cloned sheep Dolly was born after 277 eggs were used for SCNT, which created 29 viable embryos. Only three of these embryos survived until birth, and only one survived to adulthood.[14] As the procedure could not be automated, and had to be performed manually under a microscope, SCNT was very resource intensive. The biochemistry involved in reprogramming the differentiated somatic cell nucleus and activating the recipient egg was also far from being well understood. However, by 2014 researchers were reporting cloning success rates of seven to eight out of ten[15] and in 2016, a Korean Company Sooam Biotech was reported to be producing 500 cloned embryos per day.[16]

In SCNT, not all of the donor cell’s genetic information is transferred, as the donor cell’s mitochondria that contain their own mitochondrial DNA are left behind. The resulting hybrid cells retain those mitochondrial structures which originally belonged to the egg. As a consequence, clones such as Dolly that are born from SCNT are not perfect copies of the donor of the nucleus.

Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, cloning, or asexual propagation,[17] has been common practice in the horticultural world for hundreds of years.

The term clone is used in horticulture to refer to descendants of a single plant which were produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction.[18] As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana.[19] Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation.

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies naturally. Parts of an individual plant may become detached by fragmentation and grow on to become separate clonal individuals. A common example is in the vegetative reproduction of moss and liverwort gametophyte clones by means of gemmae. Some vascular plants e.g. dandelion and certain viviparous grasses also form seeds asexually, termed apomixis, resulting in clonal populations of genetically identical individuals.

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes,[20] fish (for example the hammerhead shark[21]), the Komodo dragon[21] and lizards. The growth and development occurs without fertilization by a male. In plants, parthenogenesis means the development of an embryo from an unfertilized egg cell, and is a component process of apomixis. In species that use the XY sex-determination system, the offspring will always be female. An example is the little fire ant (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments.

Artificial cloning of organisms may also be called reproductive cloning.

Hans Spemann, a German embryologist was awarded a Nobel Prize in Physiology or Medicine in 1935 for his discovery of the effect now known as embryonic induction, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs. In 1928 he and his student, Hilde Mangold, were the first to perform somatic-cell nuclear transfer using amphibian embryos one of the first steps towards cloning.[22]

Reproductive cloning generally uses “somatic cell nuclear transfer” (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg from which the nucleus has been removed, or to a cell from a blastocyst from which the nucleus has been removed.[23] If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this mitochondrial DNA is wholly from the cytoplasmic donor’s egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Artificial embryo splitting or embryo twinning, a technique that creates monozygotic twins from a single embryo, is not considered in the same fashion as other methods of cloning. During that procedure, a donor embryo is split in two distinct embryos, that can then be transferred via embryo transfer. It is optimally performed at the 6- to 8-cell stage, where it can be used as an expansion of IVF to increase the number of available embryos.[24] If both embryos are successful, it gives rise to monozygotic (identical) twins.

Dolly, a Finn-Dorset ewe, was the first mammal to have been successfully cloned from an adult somatic cell. Dolly was formed by taking a cell from the udder of her 6-year old biological mother.[25] Dolly’s embryo was created by taking the cell and inserting it into a sheep ovum. It took 434 attempts before an embryo was successful.[26] The embryo was then placed inside a female sheep that went through a normal pregnancy.[27] She was cloned at the Roslin Institute in Scotland by British scientists Sir Ian Wilmut and Keith Campbell and lived there from her birth in 1996 until her death in 2003 when she was six. She was born on 5 July 1996 but not announced to the world until 22 February 1997.[28] Her stuffed remains were placed at Edinburgh’s Royal Museum, part of the National Museums of Scotland.[29]

Dolly was publicly significant because the effort showed that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, can be reprogrammed to grow an entirely new organism. Before this demonstration, it had been shown by John Gurdon that nuclei from differentiated cells could give rise to an entire organism after transplantation into an enucleated egg.[30] However, this concept was not yet demonstrated in a mammalian system.

The first mammalian cloning (resulting in Dolly the sheep) had a success rate of 29 embryos per 277 fertilized eggs, which produced three lambs at birth, one of which lived. In a bovine experiment involving 70 cloned calves, one-third of the calves died young. The first successfully cloned horse, Prometea, took 814 attempts. Notably, although the first[clarification needed] clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the sheep had pathologies resembling accelerated aging. Scientists speculated that Dolly’s death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly’s early death due to respiratory infection was unrelated to deficiencies with the cloning process. This idea that the nuclei have not irreversibly aged was shown in 2013 to be true for mice.[31]

Dolly was named after performer Dolly Parton because the cells cloned to make her were from a mammary gland cell, and Parton is known for her ample cleavage.[32]

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Notable experiments include:

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissues. It does not refer to the natural conception and delivery of identical twins. The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass legislation regarding human cloning and its legality. As of right now, scientists have no intention of trying to clone people and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.[63]

Two commonly discussed types of theoretical human cloning are therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014[update]. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.[64]

There are a variety of ethical positions regarding the possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Advocates support development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants,[65] to avoid the need for immunosuppressive drugs,[64] and to stave off the effects of aging.[66] Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.[67]

Opponents of cloning have concerns that technology is not yet developed enough to be safe[68] and that it could be prone to abuse (leading to the generation of humans from whom organs and tissues would be harvested),[69][70] as well as concerns about how cloned individuals could integrate with families and with society at large.[71][72]

Religious groups are divided, with some opposing the technology as usurping “God’s place” and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.[73][74]

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die,[75][76] and while food from cloned animals has been approved by the US FDA,[77][78] its use is opposed by groups concerned about food safety.[79][80][81]

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream. Possible implications of this were dramatized in the 1984 novel Carnosaur and the 1990 novel Jurassic Park.[82][83] The best current cloning techniques have an average success rate of 9.4 percent[84] (and as high as 25 percent[31]) when working with familiar species such as mice,[note 1] while cloning wild animals is usually less than 1 percent successful.[87] Several tissue banks have come into existence, including the “Frozen Zoo” at the San Diego Zoo, to store frozen tissue from the world’s rarest and most endangered species.[82][88][89]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean ibex) were frozen in liquid nitrogen immediately after it died in 2000. Researchers are also considering cloning endangered species such as the giant panda and cheetah.

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the thylacine (Tasmanian tiger), at the time extinct for about 65 years, using polymerase chain reaction.[90] However, on 15 February 2005 the museum announced that it was stopping the project after tests showed the specimens’ DNA had been too badly degraded by the (ethanol) preservative. On 15 May 2005 it was announced that the thylacine project would be revived, with new participation from researchers in New South Wales and Victoria.

In 2003, for the first time, an extinct animal, the Pyrenean ibex mentioned above was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved frozen cell nucleus of the skin samples from 2001 and domestic goat egg-cells. The ibex died shortly after birth due to physical defects in its lungs.[91]

One of the most anticipated targets for cloning was once the woolly mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama, saying that they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.[92][93] It was noted, however that the result, if possible, would be an elephant-mammoth hybrid rather than a true mammoth.[94] Another problem is the survival of the reconstructed mammoth: ruminants rely on a symbiosis with specific microbiota in their stomachs for digestion.[94]

Scientists at the University of Newcastle and University of New South Wales announced in March 2013 that the very recently extinct gastric-brooding frog would be the subject of a cloning attempt to resurrect the species.[95]

Many such “de-extinction” projects are described in the Long Now Foundation’s Revive and Restore Project.[96]

After an eight-year project involving the use of a pioneering cloning technique, Japanese researchers created 25 generations of healthy cloned mice with normal lifespans, demonstrating that clones are not intrinsically shorter-lived than naturally born animals.[31][97] Other sources have noted that the offspring of clones tend to be healthier than the original clones and indistinguishable from animals produced naturally.[98]

Dolly the sheep was created from a six year old cell sample from a mammary gland. Because of this, she aged quicker than other naturally born animals because she was started from already aging cells. She died prematurely at six years old, not only from her age but from respiratory issues and severe arthritis.[citation needed][dubious discuss]

A detailed study released in 2016 and less detailed studies by others suggest that once cloned animals get past the first month or two of life they are generally healthy. However, early pregnancy loss and neonatal losses are still greater with cloning than natural conception or assisted reproduction (IVF). Current research is attempting to overcome these problems.[32]

Discussion of cloning in the popular media often presents the subject negatively. In an article in the 8 November 1993 article of Time, cloning was portrayed in a negative way, modifying Michelangelo’s Creation of Adam to depict Adam with five identical hands.[99] Newsweek’s 10 March 1997 issue also critiqued the ethics of human cloning, and included a graphic depicting identical babies in beakers.[100]

The concept of cloning, particularly human cloning, has featured a wide variety of science fiction works. An early fictional depiction of cloning is Bokanovsky’s Process which features in Aldous Huxley’s 1931 dystopian novel Brave New World. The process is applied to fertilized human eggs in vitro, causing them to split into identical genetic copies of the original.[101][102] Following renewed interest in cloning in the 1950s, the subject was explored further in works such as Poul Anderson’s 1953 story UN-Man, which describes a technology called “exogenesis”, and Gordon Rattray Taylor’s book The Biological Time Bomb, which popularised the term “cloning” in 1963.[103]

Cloning is a recurring theme in a number of contemporary science fiction films, ranging from action films such as Jurassic Park (1993), Alien Resurrection (1997), The 6th Day (2000), Resident Evil (2002), Star Wars: Episode II (2002) and The Island (2005), to comedies such as Woody Allen’s 1973 film Sleeper.[104]

The process of cloning is represented variously in fiction. Many works depict the artificial creation of humans by a method of growing cells from a tissue or DNA sample; the replication may be instantaneous, or take place through slow growth of human embryos in artificial wombs. In the long-running British television series Doctor Who, the Fourth Doctor and his companion Leela were cloned in a matter of seconds from DNA samples (“The Invisible Enemy”, 1977) and then in an apparent homage to the 1966 film Fantastic Voyage shrunk to microscopic size in order to enter the Doctor’s body to combat an alien virus. The clones in this story are short-lived, and can only survive a matter of minutes before they expire.[105] Science fiction films such as The Matrix and Star Wars: Episode II Attack of the Clones have featured scenes of human foetuses being cultured on an industrial scale in mechanical tanks.[106]

Cloning humans from body parts is also a common theme in science fiction. Cloning features strongly among the science fiction conventions parodied in Woody Allen’s Sleeper, the plot of which centres around an attempt to clone an assassinated dictator from his disembodied nose.[107] In the 2008 Doctor Who story “Journey’s End”, a duplicate version of the Tenth Doctor spontaneously grows from his severed hand, which had been cut off in a sword fight during an earlier episode.[108]

After the death of her beloved 14-year old Coton de Tulear named Samantha in late 2017, Barbra Streisand announced that she had cloned the dog, and was now “waiting for [the two cloned pups] to get older so [she] can see if they have [Samantha’s] brown eyes and her seriousness.” [109] The operation cost $50,000 through the pet cloning company ViaGen.

Science fiction has used cloning, most commonly and specifically human cloning, to raise the controversial questions of identity.[110][111] A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity, especially nature and nurture. The story, set in the near future, is structured around the conflict between a father (Salter) and his sons (Bernard 1, Bernard 2, and Michael Black) two of whom are clones of the first one. A Number was adapted by Caryl Churchill for television, in a co-production between the BBC and HBO Films.[112]

In 2012, a Japanese television series named “Bunshin” was created. The story’s main character, Mariko, is a woman studying child welfare in Hokkaido. She grew up always doubtful about the love from her mother, who looked nothing like her and who died nine years before. One day, she finds some of her mother’s belongings at a relative’s house, and heads to Tokyo to seek out the truth behind her birth. She later discovered that she was a clone.[113]

In the 2013 television series Orphan Black, cloning is used as a scientific study on the behavioral adaptation of the clones.[114] In a similar vein, the book The Double by Nobel Prize winner Jos Saramago explores the emotional experience of a man who discovers that he is a clone.[115]

Cloning has been used in fiction as a way of recreating historical figures. In the 1976 Ira Levin novel The Boys from Brazil and its 1978 film adaptation, Josef Mengele uses cloning to create copies of Adolf Hitler.[116]

In Michael Crichton’s 1990 novel Jurassic Park, which spawned a series of Jurassic Park feature films, a bioengineering company develops a technique to resurrect extinct species of dinosaurs by creating cloned creatures using DNA extracted from fossils. The cloned dinosaurs are used to populate the Jurassic Park wildlife park for the entertainment of visitors. The scheme goes disastrously wrong when the dinosaurs escape their enclosures. Despite being selectively cloned as females to prevent them from breeding, the dinosaurs develop the ability to reproduce through parthenogenesis.[117]

The use of cloning for military purposes has also been explored in several fictional works. In Doctor Who, an alien race of armour-clad, warlike beings called Sontarans was introduced in the 1973 serial “The Time Warrior”. Sontarans are depicted as squat, bald creatures who have been genetically engineered for combat. Their weak spot is a “probic vent”, a small socket at the back of their neck which is associated with the cloning process.[118] The concept of cloned soldiers being bred for combat was revisited in “The Doctor’s Daughter” (2008), when the Doctor’s DNA is used to create a female warrior called Jenny.[119]

The 1977 film Star Wars was set against the backdrop of a historical conflict called the Clone Wars. The events of this war were not fully explored until the prequel films Attack of the Clones (2002) and Revenge of the Sith (2005), which depict a space war waged by a massive army of heavily armoured clone troopers that leads to the foundation of the Galactic Empire. Cloned soldiers are “manufactured” on an industrial scale, genetically conditioned for obedience and combat effectiveness. It is also revealed that the popular character Boba Fett originated as a clone of Jango Fett, a mercenary who served as the genetic template for the clone troopers.[120][121]

Cloning has appeared in many video games. In Metal Gear Solid, the characters Solid Snake and Liquid Snake were born in a secret project as cloned soldiers. In Halo, cloning technology is shown to recreate organs. In addition, the Factions of Halo#United Nations Space Command uses cloning when it abducts children to train as supersoldiers. Here, non-clone children are trained as soldiers while the clones covertly replace the abducted children at home.

A recurring sub-theme of cloning fiction is the use of clones as a supply of organs for transplantation. The 2005 Kazuo Ishiguro novel Never Let Me Go and the 2010 film adaption[122] are set in an alternate history in which cloned humans are created for the sole purpose of providing organ donations to naturally born humans, despite the fact that they are fully sentient and self-aware. The 2005 film The Island[123] revolves around a similar plot, with the exception that the clones are unaware of the reason for their existence. In Raymond Han’s 2017 novel, The Mind Clones Trilogy,[124] a dictator who suffered a terminal illness sought to implant his mind clone into his son’s mind so that he could continue to rule the country. In another part of the trilogy, usurpers plotted to replace members of the Chinese Politburo Standing Committee using look-alike human clones.

The exploitation of human clones for dangerous and undesirable work was examined in the 2009 British science fiction film Moon.[125] In the futuristic novel Cloud Atlas and subsequent film, one of the story lines focuses on a genetically-engineered fabricant clone named Sonmi~451, one of millions raised in an artificial “wombtank,” destined to serve from birth. She is one of thousands created for manual and emotional labor; Sonmi herself works as a server in a restaurant. She later discovers that the sole source of food for clones, called ‘Soap’, is manufactured from the clones themselves.[126]

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Cloning – Wikipedia

Amazon Aurora Fast Database Cloning | AWS News Blog

Today, I want to quickly show off a feature of Amazon Aurora that I find incredibly useful: Fast Database Cloning. By taking advantage of Auroras underlying distributed storage engine youre able to quickly and cheaply create a copy-on-write clone of your database.

In my career Ive frequently spent time waiting on some representative sample of data to use in development, experiments, or analytics. If I had a 2TB database it could take hours just waiting for a copy of the data to be ready before I could peform my tasks. Even within RDS MySQL, I would still have to wait several hours for a snapshot copy to complete before I was able to test a schema migration or perform some analytics. Aurora solves this problem in a very interesting way.

The distributed storage engine for Aurora allows us to do things which are normally not feasible or cost-effective with a traditional database engine. By creating pointers to individual pages of data the storage engine enables fast database cloning. Then, when you make changes to the data in the source or the clone, a copy-on-write protocol creates a new copy of that page and updates the pointers. This means my 2TB snapshot restore job that used to take an hour is now ready in about 5 minutes and most of that time is spent provisioning a new RDS instance.

The time it takes to create the clone is independent of the size of the database since were pointing at the same storage. It also makes cloning a very cost-effective operation since I only pay storage costs for the changed pages instead of an entire copy. The database clone is still a regular Aurora Database Cluster with all the same durability guarentees.

Lets clone a database. First, Ill select an Aurora (MySQL) instance and select create-clone from the Instance Actions.

Next Ill name our clone dolly-the-sheep and provision it.

It took about 5 minutes and 30 seconds for my clone to become available and I started making some large schema changes and saw no performance impact. The schema changes themselves completed faster than they would have on traditional MySQL due to improvements the Aurora team made to enable faster DDL operations. I could subsequently create a clone-of-a-clone or even a clone-of-a-clone-of-a-clone (and so on) if I wanted to have another team member perform some tests on my schema changes while I continued to make changes of my own. Its important to note here that clones are first class databases from the perspective of RDS. I still have all of the features that every other Aurora database supports: snapshots, backups, monitoring and more.

I hope this feature will allow you and your teams to save a lot of time and money on experimenting and developing applications based on Amazon Aurora. You can read more about this feature in the Amazon Aurora User Guide and I strongly suggest following the AWS Database Blog. Anurag Guptas posts on quorums and Amazon Aurora storage are particularly interesting.

Have follow-up questions or feedback? Ping us at aurora-pm@amazon.com, or leave a comment here. Wed love to get your thoughts and suggestions.

Randall

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Amazon Aurora Fast Database Cloning | AWS News Blog

Free cloning Essays and Papers – 123helpme.com

– The Pleistocene epoch spanned from 1.8 million years ago to 10,000 years ago [1]. Many genera and even species such as conifers, mosses, flowering plants, insects, mollusks, birds, and mammals from that era still survive today [1]. Others, such as the long-horned bison, saber-toothed cats, giant ground sloths, and the mammoth did not survive [1]. The woolly mammoth was commonly found during the last ice age [2]. These animals were similar in size to todays elephants but were adapted for living in the extremely cold conditions typical of an ice age [2]…. [tags: mammoths, ice age, extinct, climate]

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Dolly (sheep) – Wikipedia

Dolly (5 July 1996 14 February 2003) was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer.

Dolly was cloned by Keith Campbell, Ian Wilmut and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland, and the biotechnology company PPL Therapeutics, based near Edinburgh. The funding for Dolly’s cloning was provided by PPL Therapeutics and the Ministry of Agriculture.[2] She was born on 5 July 1996 and died from a progressive lung disease five months before her seventh birthday (the disease was not considered related to her being a clone).[3] She has been called “the world’s most famous sheep” by sources including BBC News and Scientific American.[4][5]

The cell used as the donor for the cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. On Dolly’s name, Wilmut stated “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s”.[1]

Dolly was born on 5 July 1996 and had three mothers: one provided the egg, another the DNA, and a third carried the cloned embryo to term.[6] She was created using the technique of somatic cell nuclear transfer, where the cell nucleus from an adult cell is transferred into an unfertilized oocyte (developing egg cell) that has had its cell nucleus removed. The hybrid cell is then stimulated to divide by an electric shock, and when it develops into a blastocyst it is implanted in a surrogate mother.[7] Dolly was the first clone produced from a cell taken from an adult mammal.[8][9] The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting to an embryonic totipotent state, creating a cell that can then go on to develop into any part of an animal.[10] Dolly’s existence was announced to the public on 22 February 1997.[1] It gained much attention in the media. A commercial with Scottish scientists playing with sheep was aired on TV, and a special report in Time magazine featured Dolly the sheep.[2] Science featured Dolly as the breakthrough of the year. Even though Dolly was not the first animal cloned, she received media attention because she was the first cloned from an adult cell.[11]

Dolly lived her entire life at the Roslin Institute in Midlothian.[12] There she was bred with a Welsh Mountain ram and produced six lambs in total. Her first lamb, named Bonnie, was born in April 1998.[3] The next year Dolly produced twin lambs Sally and Rosie, and she gave birth to triplets Lucy, Darcy and Cotton in 2000.[13] In late 2001, at the age of four, Dolly developed arthritis and began to walk stiffly. This was treated with anti-inflammatory drugs.[14]

On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis.[15] A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years. A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte,[16] which is a fairly common disease of sheep and is caused by the retrovirus JSRV.[17] Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease.[15] Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons.

Some in the press speculated that a contributing factor to Dolly’s death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned.[18] One basis for this idea was the finding that Dolly’s telomeres were short, which is typically a result of the aging process.[19][20] The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.[18]

In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly. The first study to review the long-term health outcomes of cloning, the authors found no evidence of late-onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded “We could find no evidence, therefore, of a detrimental long-term effect of cloning by SCNT on the health of aged offspring among our cohort.”[21][22]

After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs,[23][24] deer,[25] horses[26] and bulls.[27] The attempt to clone argali (mountain sheep) did not produce viable embryos. The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring.[28] The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development.[29][30] Making cloned mammals was highly inefficient in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts. By 2014 Chinese scientists were reported to have 7080% success rates cloning pigs[24] and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day.[31] Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.[32]

Cloning may have uses in preserving endangered species and may become a viable tool for reviving extinct species.[33] In January 2009, scientists from the Centre of Food Technology and Research of Aragon, in northern Spain announced the cloning of the Pyrenean ibex, a form of wild mountain goat, which was officially declared extinct in 2000. Although the newborn ibex died shortly after birth due to physical defects in its lungs, it is the first time an extinct animal has been cloned, and may open doors for saving endangered and newly extinct species by resurrecting them from frozen tissue.[34][35]

In July 2016, four identical clones of Dolly (Daisy, Debbie, Dianna, and Denise) were alive and healthy at nine years old.[36][37]

Scientific American concluded in 2016 that the main legacy of Dolly the sheep has not been cloning of animals but in advances into stem cell research.[38] After Dolly, researchers realised that ordinary cells could be reprogrammed to induced pluripotent stem cells which can be grown into any tissue.[39]

The first successful cloning of a primate species using the same method for producing Dolly was reported in January 2018. Two identical clones of a macaque monkey, Zhong Zhong and Hua Hua, were created by researchers in China and were born in late 2017.[40][41][42][43]

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Dolly (sheep) – Wikipedia

What is Cloning – Learn.Genetics

Many people first heard of cloning when Dolly the Sheep showed up on the scene in 1997. Artificial cloning technologies have been around for much longer than Dolly, though.

There are two ways to make an exact genetic copy of an organism in a lab: artificial embryo twinning and somatic cell nuclear transfer.

Artificial embryo twinning is a relatively low-tech way to make clones. As the name suggests, this technique mimics the natural process that creates identical twins.

In nature, twins form very early in development when the embryo splits in two. Twinning happens in the first days after egg and sperm join, while the embryo is made of just a small number of unspecialized cells. Each half of the embryo continues dividing on its own, ultimately developing into separate, complete individuals. Since they developed from the same fertilized egg, the resulting individuals are genetically identical.

Artificial embryo twinning uses the same approach, but it is carried out in a Petri dish instead of inside the mother. A very early embryo is separated into individual cells, which are allowed to divide and develop for a short time in the Petri dish. The embryos are then placed into a surrogate mother, where they finish developing. Again, since all the embryos came from the same fertilized egg, they are genetically identical.

Somatic cell nuclear transfer (SCNT), also called nuclear transfer, uses a different approach than artificial embryo twinning, but it produces the same result: an exact genetic copy, or clone, of an individual. This was the method used to create Dolly the Sheep.

What does SCNT mean? Let’s take it apart:

Somatic cell: A somatic cell is any cell in the body other than sperm and egg, the two types of reproductive cells. Reproductive cells are also called germ cells. In mammals, every somatic cell has two complete sets of chromosomes, whereas the germ cells have only one complete set.

Nuclear: The nucleus is a compartment that holds the cell’s DNA. The DNA is divided into packages called chromosomes, and it contains all the information needed to form an organism. It’s small differences in our DNA that make each of us unique.

Transfer: Moving an object from one place to another. To make Dolly, researchers isolated a somatic cell from an adult female sheep. Next they removed the nucleus and all of its DNA from an egg cell. Then they transferred the nucleus from the somatic cell to the egg cell. After a couple of chemical tweaks, the egg cell, with its new nucleus, was behaving just like a freshly fertilized egg. It developed into an embryo, which was implanted into a surrogate mother and carried to term. (The transfer step is most often done using an electrical current to fuse the membranes of the egg and the somatic cell.)

The lamb, Dolly, was an exact genetic replica of the adult female sheep that donated the somatic cell. She was the first-ever mammal to be cloned from an adult somatic cell.

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What is Cloning – Learn.Genetics

Cloning Fact Sheet – National Human Genome Research Institute …

CloningWhat is cloning?

The term cloning describes a number of different processes that can be used to produce genetically identical copies of a biological entity. The copied material, which has the same genetic makeup as the original, is referred to as a clone.

Researchers have cloned a wide range of biological materials, including genes, cells, tissues and even entire organisms, such as a sheep.

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Yes. In nature, some plants and single-celled organisms, such as bacteria, produce genetically identical offspring through a process called asexual reproduction. In asexual reproduction, a new individual is generated from a copy of a single cell from the parent organism.

Natural clones, also known as identical twins, occur in humans and other mammals. These twins are produced when a fertilized egg splits, creating two or more embryos that carry almost identical DNA. Identical twins have nearly the same genetic makeup as each other, but they are genetically different from either parent.

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There are three different types of artificial cloning: gene cloning, reproductive cloning and therapeutic cloning.

Gene cloning produces copies of genes or segments of DNA. Reproductive cloning produces copies of whole animals. Therapeutic cloning produces embryonic stem cells for experiments aimed at creating tissues to replace injured or diseased tissues.

Gene cloning, also known as DNA cloning, is a very different process from reproductive and therapeutic cloning. Reproductive and therapeutic cloning share many of the same techniques, but are done for different purposes.

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Gene cloning is the most common type of cloning done by researchers at the National Human Genome Research Institute (NHGRI). NHGRI researchers have not cloned any mammals and NHGRI does not clone humans.

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Researchers routinely use cloning techniques to make copies of genes that they wish to study. The procedure consists of inserting a gene from one organism, often referred to as “foreign DNA,” into the genetic material of a carrier called a vector. Examples of vectors include bacteria, yeast cells, viruses or plasmids, which are small DNA circles carried by bacteria. After the gene is inserted, the vector is placed in laboratory conditions that prompt it to multiply, resulting in the gene being copied many times over.

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In reproductive cloning, researchers remove a mature somatic cell, such as a skin cell, from an animal that they wish to copy. They then transfer the DNA of the donor animal’s somatic cell into an egg cell, or oocyte, that has had its own DNA-containing nucleus removed.

Researchers can add the DNA from the somatic cell to the empty egg in two different ways. In the first method, they remove the DNA-containing nucleus of the somatic cell with a needle and inject it into the empty egg. In the second approach, they use an electrical current to fuse the entire somatic cell with the empty egg.

In both processes, the egg is allowed to develop into an early-stage embryo in the test-tube and then is implanted into the womb of an adult female animal.

Ultimately, the adult female gives birth to an animal that has the same genetic make up as the animal that donated the somatic cell. This young animal is referred to as a clone. Reproductive cloning may require the use of a surrogate mother to allow development of the cloned embryo, as was the case for the most famous cloned organism, Dolly the sheep.

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Over the last 50 years, scientists have conducted cloning experiments in a wide range of animals using a variety of techniques. In 1979, researchers produced the first genetically identical mice by splitting mouse embryos in the test tube and then implanting the resulting embryos into the wombs of adult female mice. Shortly after that, researchers produced the first genetically identical cows, sheep and chickens by transferring the nucleus of a cell taken from an early embryo into an egg that had been emptied of its nucleus.

It was not until 1996, however, that researchers succeeded in cloning the first mammal from a mature (somatic) cell taken from an adult animal. After 276 attempts, Scottish researchers finally produced Dolly, the lamb from the udder cell of a 6-year-old sheep. Two years later, researchers in Japan cloned eight calves from a single cow, but only four survived.

Besides cattle and sheep, other mammals that have been cloned from somatic cells include: cat, deer, dog, horse, mule, ox, rabbit and rat. In addition, a rhesus monkey has been cloned by embryo splitting.

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Despite several highly publicized claims, human cloning still appears to be fiction. There currently is no solid scientific evidence that anyone has cloned human embryos.

In 1998, scientists in South Korea claimed to have successfully cloned a human embryo, but said the experiment was interrupted very early when the clone was just a group of four cells. In 2002, Clonaid, part of a religious group that believes humans were created by extraterrestrials, held a news conference to announce the birth of what it claimed to be the first cloned human, a girl named Eve. However, despite repeated requests by the research community and the news media, Clonaid never provided any evidence to confirm the existence of this clone or the other 12 human clones it purportedly created.

In 2004, a group led by Woo-Suk Hwang of Seoul National University in South Korea published a paper in the journal Science in which it claimed to have created a cloned human embryo in a test tube. However, an independent scientific committee later found no proof to support the claim and, in January 2006, Science announced that Hwang’s paper had been retracted.

From a technical perspective, cloning humans and other primates is more difficult than in other mammals. One reason is that two proteins essential to cell division, known as spindle proteins, are located very close to the chromosomes in primate eggs. Consequently, removal of the egg’s nucleus to make room for the donor nucleus also removes the spindle proteins, interfering with cell division. In other mammals, such as cats, rabbits and mice, the two spindle proteins are spread throughout the egg. So, removal of the egg’s nucleus does not result in loss of spindle proteins. In addition, some dyes and the ultraviolet light used to remove the egg’s nucleus can damage the primate cell and prevent it from growing.

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No. Clones do not always look identical. Although clones share the same genetic material, the environment also plays a big role in how an organism turns out.

For example, the first cat to be cloned, named Cc, is a female calico cat that looks very different from her mother. The explanation for the difference is that the color and pattern of the coats of cats cannot be attributed exclusively to genes. A biological phenomenon involving inactivation of the X chromosome (See sex chromosome) in every cell of the female cat (which has two X chromosomes) determines which coat color genes are switched off and which are switched on. The distribution of X inactivation, which seems to occur randomly, determines the appearance of the cat’s coat.

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Reproductive cloning may enable researchers to make copies of animals with the potential benefits for the fields of medicine and agriculture.

For instance, the same Scottish researchers who cloned Dolly have cloned other sheep that have been genetically modified to produce milk that contains a human protein essential for blood clotting. The hope is that someday this protein can be purified from the milk and given to humans whose blood does not clot properly. Another possible use of cloned animals is for testing new drugs and treatment strategies. The great advantage of using cloned animals for drug testing is that they are all genetically identical, which means their responses to the drugs should be uniform rather than variable as seen in animals with different genetic make-ups.

After consulting with many independent scientists and experts in cloning, the U.S. Food and Drug Administration (FDA) decided in January 2008 that meat and milk from cloned animals, such as cattle, pigs and goats, are as safe as those from non-cloned animals. The FDA action means that researchers are now free to using cloning methods to make copies of animals with desirable agricultural traits, such as high milk production or lean meat. However, because cloning is still very expensive, it will likely take many years until food products from cloned animals actually appear in supermarkets.

Another application is to create clones to build populations of endangered, or possibly even extinct, species of animals. In 2001, researchers produced the first clone of an endangered species: a type of Asian ox known as a guar. Sadly, the baby guar, which had developed inside a surrogate cow mother, died just a few days after its birth. In 2003, another endangered type of ox, called the Banteg, was successfully cloned. Soon after, three African wildcats were cloned using frozen embryos as a source of DNA. Although some experts think cloning can save many species that would otherwise disappear, others argue that cloning produces a population of genetically identical individuals that lack the genetic variability necessary for species survival.

Some people also have expressed interest in having their deceased pets cloned in the hope of getting a similar animal to replace the dead one. But as shown by Cc the cloned cat, a clone may not turn out exactly like the original pet whose DNA was used to make the clone.

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Reproductive cloning is a very inefficient technique and most cloned animal embryos cannot develop into healthy individuals. For instance, Dolly was the only clone to be born live out of a total of 277 cloned embryos. This very low efficiency, combined with safety concerns, presents a serious obstacle to the application of reproductive cloning.

Researchers have observed some adverse health effects in sheep and other mammals that have been cloned. These include an increase in birth size and a variety of defects in vital organs, such as the liver, brain and heart. Other consequences include premature aging and problems with the immune system. Another potential problem centers on the relative age of the cloned cell’s chromosomes. As cells go through their normal rounds of division, the tips of the chromosomes, called telomeres, shrink. Over time, the telomeres become so short that the cell can no longer divide and, consequently, the cell dies. This is part of the natural aging process that seems to happen in all cell types. As a consequence, clones created from a cell taken from an adult might have chromosomes that are already shorter than normal, which may condemn the clones’ cells to a shorter life span. Indeed, Dolly, who was cloned from the cell of a 6-year-old sheep, had chromosomes that were shorter than those of other sheep her age. Dolly died when she was six years old, about half the average sheep’s 12-year lifespan.

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Therapeutic cloning involves creating a cloned embryo for the sole purpose of producing embryonic stem cells with the same DNA as the donor cell. These stem cells can be used in experiments aimed at understanding disease and developing new treatments for disease. To date, there is no evidence that human embryos have been produced for therapeutic cloning.

The richest source of embryonic stem cells is tissue formed during the first five days after the egg has started to divide. At this stage of development, called the blastocyst, the embryo consists of a cluster of about 100 cells that can become any cell type. Stem cells are harvested from cloned embryos at this stage of development, resulting in destruction of the embryo while it is still in the test tube.

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Researchers hope to use embryonic stem cells, which have the unique ability to generate virtually all types of cells in an organism, to grow healthy tissues in the laboratory that can be used replace injured or diseased tissues. In addition, it may be possible to learn more about the molecular causes of disease by studying embryonic stem cell lines from cloned embryos derived from the cells of animals or humans with different diseases. Finally, differentiated tissues derived from ES cells are excellent tools to test new therapeutic drugs.

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Many researchers think it is worthwhile to explore the use of embryonic stem cells as a path for treating human diseases. However, some experts are concerned about the striking similarities between stem cells and cancer cells. Both cell types have the ability to proliferate indefinitely and some studies show that after 60 cycles of cell division, stem cells can accumulate mutations that could lead to cancer. Therefore, the relationship between stem cells and cancer cells needs to be more clearly understood if stem cells are to be used to treat human disease.

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Gene cloning is a carefully regulated technique that is largely accepted today and used routinely in many labs worldwide. However, both reproductive and therapeutic cloning raise important ethical issues, especially as related to the potential use of these techniques in humans.

Reproductive cloning would present the potential of creating a human that is genetically identical to another person who has previously existed or who still exists. This may conflict with long-standing religious and societal values about human dignity, possibly infringing upon principles of individual freedom, identity and autonomy. However, some argue that reproductive cloning could help sterile couples fulfill their dream of parenthood. Others see human cloning as a way to avoid passing on a deleterious gene that runs in the family without having to undergo embryo screening or embryo selection.

Therapeutic cloning, while offering the potential for treating humans suffering from disease or injury, would require the destruction of human embryos in the test tube. Consequently, opponents argue that using this technique to collect embryonic stem cells is wrong, regardless of whether such cells are used to benefit sick or injured people.

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Last Reviewed: March 21, 2017

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Cloning Fact Sheet – National Human Genome Research Institute …

Cloning – Wikipedia

Cloning is the process of producing genetically identical individuals of an organism either naturally or artificially. In nature, many organisms produce clones through asexual reproduction. Cloning in biotechnology refers to the process of creating clones of organisms or copies of cells or DNA fragments (molecular cloning). Beyond biology, the term refers to the production of multiple copies of digital media or software.

The term clone, invented by J. B. S. Haldane, is derived from the Ancient Greek word kln, “twig”, referring to the process whereby a new plant can be created from a twig. In botany, the term lusus was traditionally used.[1] In horticulture, the spelling clon was used until the twentieth century; the final e came into use to indicate the vowel is a “long o” instead of a “short o”.[2][3] Since the term entered the popular lexicon in a more general context, the spelling clone has been used exclusively.

Cloning is a natural form of reproduction that has allowed life forms to spread for hundreds of millions of years. It is the reproduction method used by plants, fungi, and bacteria, and is also the way that clonal colonies reproduce themselves.[4][5] Examples of these organisms include blueberry plants, hazel trees, the Pando trees,[6][7] the Kentucky coffeetree, Myricas, and the American sweetgum.

Molecular cloning refers to the process of making multiple molecules. Cloning is commonly used to amplify DNA fragments containing whole genes, but it can also be used to amplify any DNA sequence such as promoters, non-coding sequences and randomly fragmented DNA. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Occasionally, the term cloning is misleadingly used to refer to the identification of the chromosomal location of a gene associated with a particular phenotype of interest, such as in positional cloning. In practice, localization of the gene to a chromosome or genomic region does not necessarily enable one to isolate or amplify the relevant genomic sequence. To amplify any DNA sequence in a living organism, that sequence must be linked to an origin of replication, which is a sequence of DNA capable of directing the propagation of itself and any linked sequence. However, a number of other features are needed, and a variety of specialised cloning vectors (small piece of DNA into which a foreign DNA fragment can be inserted) exist that allow protein production, affinity tagging, single stranded RNA or DNA production and a host of other molecular biology tools.

Cloning of any DNA fragment essentially involves four steps[8]

Although these steps are invariable among cloning procedures a number of alternative routes can be selected; these are summarized as a cloning strategy.

Initially, the DNA of interest needs to be isolated to provide a DNA segment of suitable size. Subsequently, a ligation procedure is used where the amplified fragment is inserted into a vector (piece of DNA). The vector (which is frequently circular) is linearised using restriction enzymes, and incubated with the fragment of interest under appropriate conditions with an enzyme called DNA ligase. Following ligation the vector with the insert of interest is transfected into cells. A number of alternative techniques are available, such as chemical sensitivation of cells, electroporation, optical injection and biolistics. Finally, the transfected cells are cultured. As the aforementioned procedures are of particularly low efficiency, there is a need to identify the cells that have been successfully transfected with the vector construct containing the desired insertion sequence in the required orientation. Modern cloning vectors include selectable antibiotic resistance markers, which allow only cells in which the vector has been transfected, to grow. Additionally, the cloning vectors may contain colour selection markers, which provide blue/white screening (alpha-factor complementation) on X-gal medium. Nevertheless, these selection steps do not absolutely guarantee that the DNA insert is present in the cells obtained. Further investigation of the resulting colonies must be required to confirm that cloning was successful. This may be accomplished by means of PCR, restriction fragment analysis and/or DNA sequencing.

Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multi-cellular organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.

A useful tissue culture technique used to clone distinct lineages of cell lines involves the use of cloning rings (cylinders).[9] In this technique a single-cell suspension of cells that have been exposed to a mutagenic agent or drug used to drive selection is plated at high dilution to create isolated colonies, each arising from a single and potentially clonal distinct cell. At an early growth stage when colonies consist of only a few cells, sterile polystyrene rings (cloning rings), which have been dipped in grease, are placed over an individual colony and a small amount of trypsin is added. Cloned cells are collected from inside the ring and transferred to a new vessel for further growth.

Somatic-cell nuclear transfer, known as SCNT, can also be used to create embryos for research or therapeutic purposes. The most likely purpose for this is to produce embryos for use in stem cell research. This process is also called “research cloning” or “therapeutic cloning.” The goal is not to create cloned human beings (called “reproductive cloning”), but rather to harvest stem cells that can be used to study human development and to potentially treat disease. While a clonal human blastocyst has been created, stem cell lines are yet to be isolated from a clonal source.[10]

Therapeutic cloning is achieved by creating embryonic stem cells in the hopes of treating diseases such as diabetes and Alzheimer’s. The process begins by removing the nucleus (containing the DNA) from an egg cell and inserting a nucleus from the adult cell to be cloned.[11] In the case of someone with Alzheimer’s disease, the nucleus from a skin cell of that patient is placed into an empty egg. The reprogrammed cell begins to develop into an embryo because the egg reacts with the transferred nucleus. The embryo will become genetically identical to the patient.[11] The embryo will then form a blastocyst which has the potential to form/become any cell in the body.[12]

The reason why SCNT is used for cloning is because somatic cells can be easily acquired and cultured in the lab. This process can either add or delete specific genomes of farm animals. A key point to remember is that cloning is achieved when the oocyte maintains its normal functions and instead of using sperm and egg genomes to replicate, the oocyte is inserted into the donor’s somatic cell nucleus.[13] The oocyte will react on the somatic cell nucleus, the same way it would on sperm cells.[13]

The process of cloning a particular farm animal using SCNT is relatively the same for all animals. The first step is to collect the somatic cells from the animal that will be cloned. The somatic cells could be used immediately or stored in the laboratory for later use.[13] The hardest part of SCNT is removing maternal DNA from an oocyte at metaphase II. Once this has been done, the somatic nucleus can be inserted into an egg cytoplasm.[13] This creates a one-cell embryo. The grouped somatic cell and egg cytoplasm are then introduced to an electrical current.[13] This energy will hopefully allow the cloned embryo to begin development. The successfully developed embryos are then placed in surrogate recipients, such as a cow or sheep in the case of farm animals.[13]

SCNT is seen as a good method for producing agriculture animals for food consumption. It successfully cloned sheep, cattle, goats, and pigs. Another benefit is SCNT is seen as a solution to clone endangered species that are on the verge of going extinct.[13] However, stresses placed on both the egg cell and the introduced nucleus can be enormous, which led to a high loss in resulting cells in early research. For example, the cloned sheep Dolly was born after 277 eggs were used for SCNT, which created 29 viable embryos. Only three of these embryos survived until birth, and only one survived to adulthood.[14] As the procedure could not be automated, and had to be performed manually under a microscope, SCNT was very resource intensive. The biochemistry involved in reprogramming the differentiated somatic cell nucleus and activating the recipient egg was also far from being well understood. However, by 2014 researchers were reporting cloning success rates of seven to eight out of ten[15] and in 2016, a Korean Company Sooam Biotech was reported to be producing 500 cloned embryos per day.[16]

In SCNT, not all of the donor cell’s genetic information is transferred, as the donor cell’s mitochondria that contain their own mitochondrial DNA are left behind. The resulting hybrid cells retain those mitochondrial structures which originally belonged to the egg. As a consequence, clones such as Dolly that are born from SCNT are not perfect copies of the donor of the nucleus.

Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, cloning, or asexual propagation,[17] has been common practice in the horticultural world for hundreds of years.

The term clone is used in horticulture to refer to descendants of a single plant which were produced by vegetative reproduction or apomixis. Many horticultural plant cultivars are clones, having been derived from a single individual, multiplied by some process other than sexual reproduction.[18] As an example, some European cultivars of grapes represent clones that have been propagated for over two millennia. Other examples are potato and banana.[19] Grafting can be regarded as cloning, since all the shoots and branches coming from the graft are genetically a clone of a single individual, but this particular kind of cloning has not come under ethical scrutiny and is generally treated as an entirely different kind of operation.

Many trees, shrubs, vines, ferns and other herbaceous perennials form clonal colonies naturally. Parts of an individual plant may become detached by fragmentation and grow on to become separate clonal individuals. A common example is in the vegetative reproduction of moss and liverwort gametophyte clones by means of gemmae. Some vascular plants e.g. dandelion and certain viviparous grasses also form seeds asexually, termed apomixis, resulting in clonal populations of genetically identical individuals.

Clonal derivation exists in nature in some animal species and is referred to as parthenogenesis (reproduction of an organism by itself without a mate). This is an asexual form of reproduction that is only found in females of some insects, crustaceans, nematodes,[20] fish (for example the hammerhead shark[21]), the Komodo dragon[21] and lizards. The growth and development occurs without fertilization by a male. In plants, parthenogenesis means the development of an embryo from an unfertilized egg cell, and is a component process of apomixis. In species that use the XY sex-determination system, the offspring will always be female. An example is the little fire ant (Wasmannia auropunctata), which is native to Central and South America but has spread throughout many tropical environments.

Artificial cloning of organisms may also be called reproductive cloning.

Hans Spemann, a German embryologist was awarded a Nobel Prize in Physiology or Medicine in 1935 for his discovery of the effect now known as embryonic induction, exercised by various parts of the embryo, that directs the development of groups of cells into particular tissues and organs. In 1928 he and his student, Hilde Mangold, were the first to perform somatic-cell nuclear transfer using amphibian embryos one of the first steps towards cloning.[22]

Reproductive cloning generally uses “somatic cell nuclear transfer” (SCNT) to create animals that are genetically identical. This process entails the transfer of a nucleus from a donor adult cell (somatic cell) to an egg from which the nucleus has been removed, or to a cell from a blastocyst from which the nucleus has been removed.[23] If the egg begins to divide normally it is transferred into the uterus of the surrogate mother. Such clones are not strictly identical since the somatic cells may contain mutations in their nuclear DNA. Additionally, the mitochondria in the cytoplasm also contains DNA and during SCNT this mitochondrial DNA is wholly from the cytoplasmic donor’s egg, thus the mitochondrial genome is not the same as that of the nucleus donor cell from which it was produced. This may have important implications for cross-species nuclear transfer in which nuclear-mitochondrial incompatibilities may lead to death.

Artificial embryo splitting or embryo twinning, a technique that creates monozygotic twins from a single embryo, is not considered in the same fashion as other methods of cloning. During that procedure, a donor embryo is split in two distinct embryos, that can then be transferred via embryo transfer. It is optimally performed at the 6- to 8-cell stage, where it can be used as an expansion of IVF to increase the number of available embryos.[24] If both embryos are successful, it gives rise to monozygotic (identical) twins.

Dolly, a Finn-Dorset ewe, was the first mammal to have been successfully cloned from an adult somatic cell. Dolly was formed by taking a cell from the udder of her 6-year old biological mother.[25] Dolly’s embryo was created by taking the cell and inserting it into a sheep ovum. It took 434 attempts before an embryo was successful.[26] The embryo was then placed inside a female sheep that went through a normal pregnancy.[27] She was cloned at the Roslin Institute in Scotland by British scientists Sir Ian Wilmut and Keith Campbell and lived there from her birth in 1996 until her death in 2003 when she was six. She was born on 5 July 1996 but not announced to the world until 22 February 1997.[28] Her stuffed remains were placed at Edinburgh’s Royal Museum, part of the National Museums of Scotland.[29]

Dolly was publicly significant because the effort showed that genetic material from a specific adult cell, programmed to express only a distinct subset of its genes, can be reprogrammed to grow an entirely new organism. Before this demonstration, it had been shown by John Gurdon that nuclei from differentiated cells could give rise to an entire organism after transplantation into an enucleated egg.[30] However, this concept was not yet demonstrated in a mammalian system.

The first mammalian cloning (resulting in Dolly the sheep) had a success rate of 29 embryos per 277 fertilized eggs, which produced three lambs at birth, one of which lived. In a bovine experiment involving 70 cloned calves, one-third of the calves died young. The first successfully cloned horse, Prometea, took 814 attempts. Notably, although the first[clarification needed] clones were frogs, no adult cloned frog has yet been produced from a somatic adult nucleus donor cell.

There were early claims that Dolly the sheep had pathologies resembling accelerated aging. Scientists speculated that Dolly’s death in 2003 was related to the shortening of telomeres, DNA-protein complexes that protect the end of linear chromosomes. However, other researchers, including Ian Wilmut who led the team that successfully cloned Dolly, argue that Dolly’s early death due to respiratory infection was unrelated to deficiencies with the cloning process. This idea that the nuclei have not irreversibly aged was shown in 2013 to be true for mice.[31]

Dolly was named after performer Dolly Parton because the cells cloned to make her were from a mammary gland cell, and Parton is known for her ample cleavage.[32]

The modern cloning techniques involving nuclear transfer have been successfully performed on several species. Notable experiments include:

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissues. It does not refer to the natural conception and delivery of identical twins. The possibility of human cloning has raised controversies. These ethical concerns have prompted several nations to pass legislation regarding human cloning and its legality. As of right now, scientists have no intention of trying to clone people and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.[63]

Two commonly discussed types of theoretical human cloning are therapeutic cloning and reproductive cloning. Therapeutic cloning would involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014[update]. Two common methods of therapeutic cloning that are being researched are somatic-cell nuclear transfer and, more recently, pluripotent stem cell induction. Reproductive cloning would involve making an entire cloned human, instead of just specific cells or tissues.[64]

There are a variety of ethical positions regarding the possibilities of cloning, especially human cloning. While many of these views are religious in origin, the questions raised by cloning are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Advocates support development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants,[65] to avoid the need for immunosuppressive drugs,[64] and to stave off the effects of aging.[66] Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to the technology.[67]

Opponents of cloning have concerns that technology is not yet developed enough to be safe[68] and that it could be prone to abuse (leading to the generation of humans from whom organs and tissues would be harvested),[69][70] as well as concerns about how cloned individuals could integrate with families and with society at large.[71][72]

Religious groups are divided, with some opposing the technology as usurping “God’s place” and, to the extent embryos are used, destroying a human life; others support therapeutic cloning’s potential life-saving benefits.[73][74]

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die,[75][76] and while food from cloned animals has been approved by the US FDA,[77][78] its use is opposed by groups concerned about food safety.[79][80][81]

Cloning, or more precisely, the reconstruction of functional DNA from extinct species has, for decades, been a dream. Possible implications of this were dramatized in the 1984 novel Carnosaur and the 1990 novel Jurassic Park.[82][83] The best current cloning techniques have an average success rate of 9.4 percent[84] (and as high as 25 percent[31]) when working with familiar species such as mice,[note 1] while cloning wild animals is usually less than 1 percent successful.[87] Several tissue banks have come into existence, including the “Frozen Zoo” at the San Diego Zoo, to store frozen tissue from the world’s rarest and most endangered species.[82][88][89]

In 2001, a cow named Bessie gave birth to a cloned Asian gaur, an endangered species, but the calf died after two days. In 2003, a banteng was successfully cloned, followed by three African wildcats from a thawed frozen embryo. These successes provided hope that similar techniques (using surrogate mothers of another species) might be used to clone extinct species. Anticipating this possibility, tissue samples from the last bucardo (Pyrenean ibex) were frozen in liquid nitrogen immediately after it died in 2000. Researchers are also considering cloning endangered species such as the giant panda and cheetah.

In 2002, geneticists at the Australian Museum announced that they had replicated DNA of the thylacine (Tasmanian tiger), at the time extinct for about 65 years, using polymerase chain reaction.[90] However, on 15 February 2005 the museum announced that it was stopping the project after tests showed the specimens’ DNA had been too badly degraded by the (ethanol) preservative. On 15 May 2005 it was announced that the thylacine project would be revived, with new participation from researchers in New South Wales and Victoria.

In 2003, for the first time, an extinct animal, the Pyrenean ibex mentioned above was cloned, at the Centre of Food Technology and Research of Aragon, using the preserved frozen cell nucleus of the skin samples from 2001 and domestic goat egg-cells. The ibex died shortly after birth due to physical defects in its lungs.[91]

One of the most anticipated targets for cloning was once the woolly mammoth, but attempts to extract DNA from frozen mammoths have been unsuccessful, though a joint Russo-Japanese team is currently working toward this goal. In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama, saying that they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.[92][93] It was noted, however that the result, if possible, would be an elephant-mammoth hybrid rather than a true mammoth.[94] Another problem is the survival of the reconstructed mammoth: ruminants rely on a symbiosis with specific microbiota in their stomachs for digestion.[94]

Scientists at the University of Newcastle and University of New South Wales announced in March 2013 that the very recently extinct gastric-brooding frog would be the subject of a cloning attempt to resurrect the species.[95]

Many such “de-extinction” projects are described in the Long Now Foundation’s Revive and Restore Project.[96]

After an eight-year project involving the use of a pioneering cloning technique, Japanese researchers created 25 generations of healthy cloned mice with normal lifespans, demonstrating that clones are not intrinsically shorter-lived than naturally born animals.[31][97] Other sources have noted that the offspring of clones tend to be healthier than the original clones and indistinguishable from animals produced naturally.[98]

Dolly the sheep was created from a six year old cell sample from a mammary gland. Because of this, she aged quicker than other naturally born animals because she was started from already aging cells. She died prematurely at six years old, not only from her age but from respiratory issues and severe arthritis.[citation needed][dubious discuss]

A detailed study released in 2016 and less detailed studies by others suggest that once cloned animals get past the first month or two of life they are generally healthy. However, early pregnancy loss and neonatal losses are still greater with cloning than natural conception or assisted reproduction (IVF). Current research is attempting to overcome these problems.[32]

Discussion of cloning in the popular media often presents the subject negatively. In an article in the 8 November 1993 article of Time, cloning was portrayed in a negative way, modifying Michelangelo’s Creation of Adam to depict Adam with five identical hands.[99] Newsweek’s 10 March 1997 issue also critiqued the ethics of human cloning, and included a graphic depicting identical babies in beakers.[100]

The concept of cloning, particularly human cloning, has featured a wide variety of science fiction works. An early fictional depiction of cloning is Bokanovsky’s Process which features in Aldous Huxley’s 1931 dystopian novel Brave New World. The process is applied to fertilized human eggs in vitro, causing them to split into identical genetic copies of the original.[101][102] Following renewed interest in cloning in the 1950s, the subject was explored further in works such as Poul Anderson’s 1953 story UN-Man, which describes a technology called “exogenesis”, and Gordon Rattray Taylor’s book The Biological Time Bomb, which popularised the term “cloning” in 1963.[103]

Cloning is a recurring theme in a number of contemporary science fiction films, ranging from action films such as Jurassic Park (1993), Alien Resurrection (1997), The 6th Day (2000), Resident Evil (2002), Star Wars: Episode II (2002) and The Island (2005), to comedies such as Woody Allen’s 1973 film Sleeper.[104]

The process of cloning is represented variously in fiction. Many works depict the artificial creation of humans by a method of growing cells from a tissue or DNA sample; the replication may be instantaneous, or take place through slow growth of human embryos in artificial wombs. In the long-running British television series Doctor Who, the Fourth Doctor and his companion Leela were cloned in a matter of seconds from DNA samples (“The Invisible Enemy”, 1977) and then in an apparent homage to the 1966 film Fantastic Voyage shrunk to microscopic size in order to enter the Doctor’s body to combat an alien virus. The clones in this story are short-lived, and can only survive a matter of minutes before they expire.[105] Science fiction films such as The Matrix and Star Wars: Episode II Attack of the Clones have featured scenes of human foetuses being cultured on an industrial scale in mechanical tanks.[106]

Cloning humans from body parts is also a common theme in science fiction. Cloning features strongly among the science fiction conventions parodied in Woody Allen’s Sleeper, the plot of which centres around an attempt to clone an assassinated dictator from his disembodied nose.[107] In the 2008 Doctor Who story “Journey’s End”, a duplicate version of the Tenth Doctor spontaneously grows from his severed hand, which had been cut off in a sword fight during an earlier episode.[108]

After the death of her beloved 14-year old Coton de Tulear named Samantha in late 2017, Barbra Streisand announced that she had cloned the dog, and was now “waiting for [the two cloned pups] to get older so [she] can see if they have [Samantha’s] brown eyes and her seriousness.” [109] The operation cost $50,000 through the pet cloning company ViaGen.

Science fiction has used cloning, most commonly and specifically human cloning, to raise the controversial questions of identity.[110][111] A Number is a 2002 play by English playwright Caryl Churchill which addresses the subject of human cloning and identity, especially nature and nurture. The story, set in the near future, is structured around the conflict between a father (Salter) and his sons (Bernard 1, Bernard 2, and Michael Black) two of whom are clones of the first one. A Number was adapted by Caryl Churchill for television, in a co-production between the BBC and HBO Films.[112]

In 2012, a Japanese television series named “Bunshin” was created. The story’s main character, Mariko, is a woman studying child welfare in Hokkaido. She grew up always doubtful about the love from her mother, who looked nothing like her and who died nine years before. One day, she finds some of her mother’s belongings at a relative’s house, and heads to Tokyo to seek out the truth behind her birth. She later discovered that she was a clone.[113]

In the 2013 television series Orphan Black, cloning is used as a scientific study on the behavioral adaptation of the clones.[114] In a similar vein, the book The Double by Nobel Prize winner Jos Saramago explores the emotional experience of a man who discovers that he is a clone.[115]

Cloning has been used in fiction as a way of recreating historical figures. In the 1976 Ira Levin novel The Boys from Brazil and its 1978 film adaptation, Josef Mengele uses cloning to create copies of Adolf Hitler.[116]

In Michael Crichton’s 1990 novel Jurassic Park, which spawned a series of Jurassic Park feature films, a bioengineering company develops a technique to resurrect extinct species of dinosaurs by creating cloned creatures using DNA extracted from fossils. The cloned dinosaurs are used to populate the Jurassic Park wildlife park for the entertainment of visitors. The scheme goes disastrously wrong when the dinosaurs escape their enclosures. Despite being selectively cloned as females to prevent them from breeding, the dinosaurs develop the ability to reproduce through parthenogenesis.[117]

The use of cloning for military purposes has also been explored in several fictional works. In Doctor Who, an alien race of armour-clad, warlike beings called Sontarans was introduced in the 1973 serial “The Time Warrior”. Sontarans are depicted as squat, bald creatures who have been genetically engineered for combat. Their weak spot is a “probic vent”, a small socket at the back of their neck which is associated with the cloning process.[118] The concept of cloned soldiers being bred for combat was revisited in “The Doctor’s Daughter” (2008), when the Doctor’s DNA is used to create a female warrior called Jenny.[119]

The 1977 film Star Wars was set against the backdrop of a historical conflict called the Clone Wars. The events of this war were not fully explored until the prequel films Attack of the Clones (2002) and Revenge of the Sith (2005), which depict a space war waged by a massive army of heavily armoured clone troopers that leads to the foundation of the Galactic Empire. Cloned soldiers are “manufactured” on an industrial scale, genetically conditioned for obedience and combat effectiveness. It is also revealed that the popular character Boba Fett originated as a clone of Jango Fett, a mercenary who served as the genetic template for the clone troopers.[120][121]

Cloning has appeared in many video games. In Metal Gear Solid, the characters Solid Snake and Liquid Snake were born in a secret project as cloned soldiers. In Halo, cloning technology is shown to recreate organs. In addition, the Factions of Halo#United Nations Space Command uses cloning when it abducts children to train as supersoldiers. Here, non-clone children are trained as soldiers while the clones covertly replace the abducted children at home.

A recurring sub-theme of cloning fiction is the use of clones as a supply of organs for transplantation. The 2005 Kazuo Ishiguro novel Never Let Me Go and the 2010 film adaption[122] are set in an alternate history in which cloned humans are created for the sole purpose of providing organ donations to naturally born humans, despite the fact that they are fully sentient and self-aware. The 2005 film The Island[123] revolves around a similar plot, with the exception that the clones are unaware of the reason for their existence. In Raymond Han’s 2017 novel, The Mind Clones Trilogy,[124] a dictator who suffered a terminal illness sought to implant his mind clone into his son’s mind so that he could continue to rule the country. In another part of the trilogy, usurpers plotted to replace members of the Chinese Politburo Standing Committee using look-alike human clones.

The exploitation of human clones for dangerous and undesirable work was examined in the 2009 British science fiction film Moon.[125] In the futuristic novel Cloud Atlas and subsequent film, one of the story lines focuses on a genetically-engineered fabricant clone named Sonmi~451, one of millions raised in an artificial “wombtank,” destined to serve from birth. She is one of thousands created for manual and emotional labor; Sonmi herself works as a server in a restaurant. She later discovers that the sole source of food for clones, called ‘Soap’, is manufactured from the clones themselves.[126]

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Cloning – Wikipedia

Dolly (sheep) – Wikipedia

Dolly (5 July 1996 14 February 2003) was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer.

Dolly was cloned by Keith Campbell, Ian Wilmut and colleagues at the Roslin Institute, part of the University of Edinburgh, Scotland, and the biotechnology company PPL Therapeutics, based near Edinburgh. The funding for Dolly’s cloning was provided by PPL Therapeutics and the Ministry of Agriculture.[2] She was born on 5 July 1996 and died from a progressive lung disease five months before her seventh birthday (the disease was not considered related to her being a clone).[3] She has been called “the world’s most famous sheep” by sources including BBC News and Scientific American.[4][5]

The cell used as the donor for the cloning of Dolly was taken from a mammary gland, and the production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. On Dolly’s name, Wilmut stated “Dolly is derived from a mammary gland cell and we couldn’t think of a more impressive pair of glands than Dolly Parton’s”.[1]

Dolly was born on 5 July 1996 and had three mothers: one provided the egg, another the DNA, and a third carried the cloned embryo to term.[6] She was created using the technique of somatic cell nuclear transfer, where the cell nucleus from an adult cell is transferred into an unfertilized oocyte (developing egg cell) that has had its cell nucleus removed. The hybrid cell is then stimulated to divide by an electric shock, and when it develops into a blastocyst it is implanted in a surrogate mother.[7] Dolly was the first clone produced from a cell taken from an adult mammal.[8][9] The production of Dolly showed that genes in the nucleus of such a mature differentiated somatic cell are still capable of reverting to an embryonic totipotent state, creating a cell that can then go on to develop into any part of an animal.[10] Dolly’s existence was announced to the public on 22 February 1997.[1] It gained much attention in the media. A commercial with Scottish scientists playing with sheep was aired on TV, and a special report in Time magazine featured Dolly the sheep.[2] Science featured Dolly as the breakthrough of the year. Even though Dolly was not the first animal cloned, she received media attention because she was the first cloned from an adult cell.[11]

Dolly lived her entire life at the Roslin Institute in Midlothian.[12] There she was bred with a Welsh Mountain ram and produced six lambs in total. Her first lamb, named Bonnie, was born in April 1998.[3] The next year Dolly produced twin lambs Sally and Rosie, and she gave birth to triplets Lucy, Darcy and Cotton in 2000.[13] In late 2001, at the age of four, Dolly developed arthritis and began to walk stiffly. This was treated with anti-inflammatory drugs.[14]

On 14 February 2003, Dolly was euthanised because she had a progressive lung disease and severe arthritis.[15] A Finn Dorset such as Dolly has a life expectancy of around 11 to 12 years, but Dolly lived 6.5 years. A post-mortem examination showed she had a form of lung cancer called ovine pulmonary adenocarcinoma, also known as Jaagsiekte,[16] which is a fairly common disease of sheep and is caused by the retrovirus JSRV.[17] Roslin scientists stated that they did not think there was a connection with Dolly being a clone, and that other sheep in the same flock had died of the same disease.[15] Such lung diseases are a particular danger for sheep kept indoors, and Dolly had to sleep inside for security reasons.

Some in the press speculated that a contributing factor to Dolly’s death was that she could have been born with a genetic age of six years, the same age as the sheep from which she was cloned.[18] One basis for this idea was the finding that Dolly’s telomeres were short, which is typically a result of the aging process.[19][20] The Roslin Institute stated that intensive health screening did not reveal any abnormalities in Dolly that could have come from advanced aging.[18]

In 2016 scientists reported no defects in thirteen cloned sheep, including four from the same cell line as Dolly. The first study to review the long-term health outcomes of cloning, the authors found no evidence of late-onset, non-communicable diseases other than some minor examples of osteoarthritis and concluded “We could find no evidence, therefore, of a detrimental long-term effect of cloning by SCNT on the health of aged offspring among our cohort.”[21][22]

After cloning was successfully demonstrated through the production of Dolly, many other large mammals were cloned, including pigs,[23][24] deer,[25] horses[26] and bulls.[27] The attempt to clone argali (mountain sheep) did not produce viable embryos. The attempt to clone a banteng bull was more successful, as were the attempts to clone mouflon (a form of wild sheep), both resulting in viable offspring.[28] The reprogramming process that cells need to go through during cloning is not perfect and embryos produced by nuclear transfer often show abnormal development.[29][30] Making cloned mammals was highly inefficient in 1996 Dolly was the only lamb that survived to adulthood from 277 attempts. By 2014 Chinese scientists were reported to have 7080% success rates cloning pigs[24] and in 2016, a Korean company, Sooam Biotech, was producing 500 cloned embryos a day.[31] Wilmut, who led the team that created Dolly, announced in 2007 that the nuclear transfer technique may never be sufficiently efficient for use in humans.[32]

Cloning may have uses in preserving endangered species and may become a viable tool for reviving extinct species.[33] In January 2009, scientists from the Centre of Food Technology and Research of Aragon, in northern Spain announced the cloning of the Pyrenean ibex, a form of wild mountain goat, which was officially declared extinct in 2000. Although the newborn ibex died shortly after birth due to physical defects in its lungs, it is the first time an extinct animal has been cloned, and may open doors for saving endangered and newly extinct species by resurrecting them from frozen tissue.[34][35]

In July 2016, four identical clones of Dolly (Daisy, Debbie, Dianna, and Denise) were alive and healthy at nine years old.[36][37]

Scientific American concluded in 2016 that the main legacy of Dolly the sheep has not been cloning of animals but in advances into stem cell research.[38] After Dolly, researchers realised that ordinary cells could be reprogrammed to induced pluripotent stem cells which can be grown into any tissue.[39]

The first successful cloning of a primate species using the same method for producing Dolly was reported in January 2018. Two identical clones of a macaque monkey, Zhong Zhong and Hua Hua, were created by researchers in China and were born in late 2017.[40][41][42][43]

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Dolly (sheep) – Wikipedia

Free cloning Essays and Papers – 123helpme.com

– The Pleistocene epoch spanned from 1.8 million years ago to 10,000 years ago [1]. Many genera and even species such as conifers, mosses, flowering plants, insects, mollusks, birds, and mammals from that era still survive today [1]. Others, such as the long-horned bison, saber-toothed cats, giant ground sloths, and the mammoth did not survive [1]. The woolly mammoth was commonly found during the last ice age [2]. These animals were similar in size to todays elephants but were adapted for living in the extremely cold conditions typical of an ice age [2]…. [tags: mammoths, ice age, extinct, climate]

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