Men's Health | 20th Anniversary of Dolly the Cloned Sheep | Men's Health Men's Health 20 years after the world was introduced to Dolly, the Cloned Sheep, we take a look back at what we've learned about cloning. The clones are still among us - Gulf Times |
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20th Anniversary of Dolly the Cloned Sheep | Men's Health - Men's Health
In 1997Dolly the sheep was introducedto the world by biologists Keith Campbell, Ian Wilmut and colleagues. Not just any lamb, Dolly was a clone. Rather than being made from a sperm and an egg, she originated from a mammary gland cell of another, no-longer-living, six-year-old Fynn Dorset ewe.
With her birth, a scientific and societal revolution was also born.
Some prominent scientistsraised doubts; it was too good to be true. But more animals were cloned: first thelaboratory mouse, thencows,goats,pigs,horses, evendogs,ferretsandcamels. By early 2000, the issue was settled: Dolly was real and cloning adults was possible.
The implications of cloning animals in our society were self-evident from the start. Our advancing ability to reprogram adult, already specialized cells and start them over as something new may one day be the key to creating cells and organs that match the immune system of each individual patient in need of replacements.
But what somehow got lost was the fact that a clone was born at day zero created from the cell of another animal that was six years old. Researchers have spent the past 20 years trying to untangle the mysteries of how clones age. How old, biologically, are these animals born from other adult animals cells?
Decades of cloning research
Dolly became an international celebrity, but she was not the first vertebrate to be cloned from a cell taken from the body of another animal. In 1962, developmental biologistJohn Gurdoncloned the first adult animalby taking a cell from the intestine of one frog and injecting it into an egg of another. Gurdons work did not go unnoticed he went on to share the2012 Nobel Prizein Physiology or Medicine. But it was Dolly who had captured our imagination. Was it because she was a warm-blooded animal, a mammal, much closer to human? If you could do it in a sheep, you could do it on us!
Dolly, along with Gurdons frogs from 35 years earlier and all the other experiments in between, redirected our scientific studies. It was amazing to see a differentiated cell an adult cell specialized to do its particular job transform into an embryonic one that could go on to give rise to all the other cells of a normal body. We researchers wondered if we could go further: Could we in the lab make an adult cell once again undifferentiated, without needing to make a cloned embryo?
A decade after Dolly was announced, stem cell researcherShynia Yamanakas teamdid just that. He went on to be the Nobel corecipient with Gurdon for showing that mature cells could bereprogrammed to become pluripotent: able to develop into any specialized adult cell.
Now we have the possibility of making individualized replacement cells potentially any kind to replace tissue damaged due to injury, genetic disorders and degeneration. Not only cells; we may soon be able to haveour own organs grown in a nonhuman host, ready to be transplanted when needed.
If Dolly was responsible for unleashing the events that culminate with new methods of making fully compatible cells and organs, then her legacy would be to improve the health of practically all human beings on this planet. And yet, I am convinced that there are even better things to come.
Dollys secrets still unfolding
In the winter of 2013, I found myself driving on the wrong side of the road through the Nottingham countryside. In contrast to the luscious landscape, I was in a state gloom; I was on my way to see Keith Campbells family after his sudden death a few weeks earlier. Keith was a smart, fun, loving friend who, along with Ian Wilmut andcolleagues at the Roslin Institute, had brought us Dolly 15 years earlier. We had met at a conference in the early 1990s, when we were both budding scientists playing around with cloning, Keith with sheep, me with cows. An extrovert by nature, he quickly dazzled me with his wit, self-deprecating humor and nonstop chat, all delivered in a thick West Midlands accent. Our friendship that began then continued until his death.
When I knocked at the door of his quaint farmhouse, my plan was to stay just a few minutes, pay my respects to his wife and leave. Five hours and several Guinnesses later, I left feeling grateful. Keith could do that to you, but this time it wasnt him, it was his latest work speaking for him. Thats because his wife very generously told me the project Keith was working on at the time of his death. I couldnt hide my excitement: Could it be possible that after 20 years, the most striking aspect of Dollys legacy was not yet revealed?
See, when Dolly was cloned, she was created using a cell from a six-year-old sheep. Andshe died at age six and a half, a premature death for a breed that lives an average of nine years or more. People assumed that an offspring cloned from an adult was starting at an age disadvantage; rather than truly being a newborn, it seemed like a clones internal age would be more advanced that the length of its own life would suggest. Thus the notion that clones biological age and their chronological one were out of sync, and that cloned animals will die young.
Some of us were convinced that if the cloning procedure was done properly, the biological clock should be reset a newborn clone would truly start at zero. We worked very hard to prove our point. We were not convinced by a single DNA analysis done in Dolly showing slightly shortertelomeres the repetitive DNA sequences at the end of chromosomes that count how many times a cell divides. We presented strong scientific evidence showing that cloned cows had all thesame molecular signs of agingas a nonclone, predicting a normal lifespan. Othersshowed the same in cloned mice. But we couldnt ignore reports from colleagues interpretingbiological signs in cloned animalsthat they attributed toincomplete resetting of the biological clock. So the jury was out.
Aging studies are very hard to do because there are only two data points that really count: date of birth and date of death. If you want to know the lifespan of an individual you have to wait until its natural death. Little did I know, that is what Keith was doing back in 2012.
That Saturday afternoon I spent in Keiths house in Nottingham, I saw a photo of the animals in Keiths latest study: several cloned Dollies, all much older than Dolly at the time she had died, and they looked terrific. I was in awe.
The data were confidential, so I had to remain silent until late last year whenthe work was posthumously published. Keiths coauthors humbly said: For those clones that survive beyond the perinatal period [] the emerging consensus, supported by the current data, is that they are healthy and seem to age normally.
These findings became even more relevant when last December researchers at theScripps Research Institutefound that induced pluripotent stem cells reprogrammed using the Yamanaka factorsretain the aging epigenetic signature of the donor individual. In other words, using these four genes to attempt to reprogram the cells does not seem to reset the biological clock.
The new Dollies are now telling us that if we take a cell from an animal of any age, and we introduce its nucleus into a nonfertilized mature egg, we can have an individual born with its lifespan fully restored. They confirmed that all signs of biological and chronological age matched between cloned and noncloned sheep.
There seems to be a natural built-in mechanism in the eggs that can rejuvenate a cell. We dont know what it is yet, but it is there. Our group as well as others are hard at work, and as soon as someone finds it, the most astonishing legacy of Dolly will be realized.
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More lessons from Dolly the sheep: Is a clone really born at age zero ... - Salon
More than seven months earlier, on July 5, 1996, they had aided a Scottish Blackface sheep in giving birth to a Finn Dorset lamb codenamed 6LL3.
Using a breakthrough technique called somatic cell nuclear transfer, scientists at Roslin took a nucleus -- the part of the cell that contains most of its genetic information -- from cells within the mammary gland of an adult sheep and stuck it inside an unfertilized egg from which the nucleus had been removed.
They stimulated the egg to develop into an embryo and planted the embryo into a surrogate mother. The lamb was dubbed Dolly, a nod to country music legend Dolly Parton and her famously ample bosom.
Years later, that same cell cluster was used to make four other sheep just like Dolly.
The lab had kept her birth secret for seven months to make the announcement coincide with the publication of the scientific paper describing the experiments that produced her, they said.
Much of the news reports had focused not on cloning sheep but on its potential for humans, said Alan Colman, who is now a visiting scholar in the Harvard University Department of Stem Cell and Regenerative Biology.
"We'd underestimated the impact the announcement would make," he said. "It was something we had prepared for, but we had been totally overwhelmed by the response."
Previously, cloning had been done using only embryonic cells, and now researchers had showed that it was possible in cells from another part of the body -- and adult body.
"At the time she was born, I was ecstatic, because no one had previously been able to use nuclear transfer to make an adult vertebrate from an adult cell," Colman said.
Despite the headlines, cloning a mammal wasn't the team's main goal. They were out to develop a more efficient way to produce genetically modified livestock.
In fact, Dolly wasn't even the first to ever be cloned. She was the first mammal cloned from an adult cell.
But scientists have learned a lot since developing the technique, and somatic cell nuclear transfer has been used in more than 20 species to make clones.
But by and large, scientists don't see a need to clone humans.
Dolly herself lived out her days at the Roslin Institute and was able to produce six lambs.
But she was euthanized at age 6 after being diagnosed with progressive lung disease and after a long battle with arthritis.
Finn Dorset sheep usually live 10 to 11 years, and her health problems seemed to confirm fears that cloned animals would age faster and die prematurely compared with animals born naturally.
This was further exemplified by Dolly's four cloned "sisters," who were recently euthanized because they too began to show symptoms of osteoarthritis.
"OA, as you may know, is a progressive disease, and we took appropriate measures to manage the condition at the time under veterinary guidance," said Kevin Sinclair, a developmental biologist at the University of Nottingham who led research on the sheep.
"These animals were in their 10th year and so coming towards the end of their natural lifespan."
To investigate this further, the team at Nottingham will now conduct postmortem examinations to truly understand what's going on inside the animals.
"The final phase of our study ... involves detailed postmortem analyses of different tissues and organs in order to gain a better insight into the aging process in these animals," Sinclair said.
The Roslin Institute donated Dolly's body to the National Museum of Scotland, where she stands to this day.
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20 years after Dolly the sheep, potential of cloning remains unclear - CNN
Image: Amazing Spider-Man #24 cover art by Alex Ross.
This weeks issue of Amazing Spider-Man started to wrap up the long, clone-tacular events of Spideys latest event series, The Clone Conspiracywhich has already given us the return of Ben Reilly as the Scarlet Spider. But now weve got confirmation of at least one major thorn in Peter Parkers side perishing... and another making a grand return.
Amazing Spider-Man #24, by Dan Slott, Christos Gage, Giuseppe Camuncoli, Cam Smith, Jason Keith, and Joe Caramagna, pretty much picks up during the final issue of the Clone Conspiracy miniseries, as the cloning virus unleashed by the Jackalne new cloned version of Ben Reillythreatens to wreak havoc across the world. As Peter Parker races to stop that from happening in that issue, we get to see the fallout of events from Bens perspective this week.
As all the other clones around him start disintegrating around him, Ben finds himself brawling with Doctor Octaviusas the two attempt to transfer their minds in the the ultimate clone template Ben and Octavius developed after a lengthy series of horrendous cloning experiments on Ben by Miles Warren, the original Jackal. Considering we knew Ben would make it out of the series alive to return to his role as the Scarlet Spider, many assumed that he would get the body... but he doesnt.
Doc Ock does, meaning that one of Peter Parkers oldest foes is back for good. This is particularly the end of a long road for Octaviuswhos technically been dead since 2012, when he swapped his mind with Peter Parkers in his dying breath in the infamous Spider-Man #700. Long story short: Otto spent several months in Peters body pretending to be a harsher Spider-Man, eventually got kicked out of Peters body by the lingering remnants of Peters subconscious, secretly transferred his mind into the body of Peters former robot assistant the Living Brain (yes, that Living Brain!), and then was eventually re-born in a clone body during Clone Conspiracy at the Jackals hands. Comic books, am I right?
Sure, Otto has swapped one clone body for anotherbut the ultimate template, unlike any other clone Warren has created over his years as a supervillain, has no defects. Unlike Bens original body, or the clones created throughout Clone Conspiracy, it does not slowly but surely degrade. For all intents and purposes, Otto Octavius has been reborn: his original mind, in a brand new (and permanent) body.
After suffering that setback, Ben actually rather conveniently manages to stabilize his own decaying clone body, thanks to the magic plot device soundwave Peter helped release in Clone Conspiracy #5 to stop all the cloned individuals around the world from turning into piles of dust and/or flesh-craving zombie clones. This whole storyline has been crazy. Thats not Bens only problem, however; the death of most of the Clones he createdamong them a whole army of clones of Warrenas the new Jackal leaves the original Miles Warren alive and well.
Infuriated by the torture Ben put him through, he promptly dons his original Jackal uniform and goes after his prized clone for vengeance... and then promptly gets killed by Ben, who lets the burning debris of his former safehouse collapse on Warren, seemingly killing off his creator for good.
I say seemingly because a) this is a comic book and no one ever dies for good, really, and b) we dont actually see Miles perish, its just heavily implied. But while Ben Reilly is now back, hes not the only major twist to Spider-Man that Clone Conspiracy has ultimately given us. One of Spider-Mans oldest villains now has a new leash on life, and another has seemingly fallen.
That is, until a Spider-Man creative team decides that a cloning storyline is a great idea again. Where clone stories go, Miles Warren follows, so its likely weve not seen the last of him yet, despite Bens best efforts.
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As Clone Conspiracy Ends, the Fates of Two Major Spider-Man Villains Are Revealed - Gizmodo
Terrific value investor Mohnish Pabrai teamed up with quant Fei Li to test a cloning strategy. Mohnish Pabrai is a fervent proponent and practitioner of cloning and mostly confines his investment universe to 13-F's of investors he thinks of as highly capable. Studies like this one on Buffett have shown 13-F's can be valuable sources of Alpha although these usually do have an important defect I'll address later. Pabrai created an ETF called the Dhandho Junoon ETF (NYSEARCA:JUNE) based on three distinct strategies of which cloning is one:
To prove his cloning strategy works Pabrai and Fei Li set up an experiment. Pabrai selected eight value managers and himself and Fei Li designed a randomization method to pick five stocks from a random portfolio between these nine managers':
Manager Number
Value Manager
1
Appaloosa Management
2
Cedar Rock Capital
3
FPA Capital
4
Greenlight Capital
5
Markel Insurance
6
Pabrai Investment Funds
7
Sequoia Fund
8
TCI Fund Management
9
ValueAct Capital
The algorithm always selected the largest (highest conviction) pick unless it was disqualified by the additional rules of the algorithm or it had already been selected.
The additional rules further weaken the test results:
Selection Criteria
No utilities, no REITs, no oil and gas exploration, no metals and mining and no multiline retailers.
Positive trailing-12-month net income
The random portfolios ended up doing really well:
Source: Forbes
Criticism
Even though the margin of outperformance is large I wouldn't put too much faith in this 10% outperformance holding up in the future.
Why didn't they run this backtest a gazillion times and publish aggregated results? It seems strange to run it just once as it is clearly a very volatile method because of the limited number of stocks chosen, the concentration in the value strategy.
What invalidates all these types of backtests is the researcher, or in this case Pabrai, starts out with a known big winner or winning group and subsequently comes up with the result they outperformed.
They use this to argue 13-F's contain valuable information that can be arbitraged and I believe that's true. But it is a flawed argument because we didn't know these managers were this good back in 2000. Some didn't even file 13-F's yet at the start date of the experiment.
When Warren Buffett wanted to make a point Hedge Funds wouldn't beat the S&P 500 he didn't say here's proof "look at my backtest". He said let's bet a million dollars to a hedge fund guy.
Source: Longbets
The additional selection criteria have nothing to do with the original premise. Why taint the results by including these. Pabrai could easily have knowledge of a particular spectacular failure by one of these 9 managers. For example the positive trailing 12 month net income criteria heightened the odds of the algorithm avoiding the spectacular Valeant (NYSE:VRX) disaster a prominent Sequoia position for a long time. Even with Valeant Sequoia outperformed but without it, the record is truly outstanding.
In addition most of the industries Pabrai selected for exclusion have underperformed the S&P 500 by a sizeable margin most especially in the later years which greatly influences compounded returns:
^SPXTR data by YCharts
^SPXTR data by YCharts
^SPXTR data by YCharts
^DJUSIM data by YCharts
^MSACMRTTR data by YCharts
My final point of criticism being that is seems a little bit unfair to include long/short managers like David Einhorn. We don't know how Einhorn manages risk exactly but he had only two down years ever. Short books generally limit volatility and it may have enabled Einhorn to be very aggressive with his long book due to eliminating some market risk. When we know after the fact, a managers bets have panned out and we can select from the great half of his portfolio as shorts aren't disclosed on 13-F's outperforming the S&P 500 starts to become easy game.
Even after my critical aside I do believe Pabrai's ETF is going to work and the 13-F strategy will work if you are good at identifying the right investors to follow.
The ETF combines strong strategies where there's compelling evidence they have been working and credible behavioral, systematic and other explanations of why they could continue to outperform.
Pabrai brandished his experiment the Shameless Portfolio and the algorithmic picks for 2017 are:
Oracle (NASDAQ:ORCL)
Berkshire Hathaway (NYSE:BRK.A) (NYSE:BRK.B)
Apple (NASDAQ:AAPL)
Microsoft (NASDAQ:MSFT)
Charter Communications (NYSE:CTR)
Apple continues to be a David Einhorn top pick and represents 14% of his long book. He's been long for a long time in addition to successfully trading the position. If you're an Apple long he's a guy worth checking on.
Berkshire Hathaway is the top position of Sequoia Fund. They have recently blemished their track record with the Valeant debacle and the Berkshire position has been maintained for a long time. It is actually fairly small given their historic position. It represents about 8% of the long book after Valeant cured them of an appetite for huge bets.
Chris Hohn's TCI Fund is betting big on Charter Communications with a 38% position according to the 13-F. TCI is London based however and they do a lot of European investments, only U.S. listed positions are revealed on the 13-F, which means the position is likely a much smaller part of the entire portfolio.
Oracle represents a 6.6% position for L.A. based First Pacific Advisors. Oracle is a popular holding among super investors of the value school but positions are generally small compared to some of the jumbo bets we've observed on the other picks.
Microsoft represents 20% of Value Act's U.S. long book. Value Act is an activist investor and they have been on the board of Microsoft for some time. They did very, very well with Microsoft but most recently added to other positions.
You can do a lot worse than buying any of these or checking out Pabrai's interesting Junoon ETF.
Disclosure: I/we have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours.
I wrote this article myself, and it expresses my own opinions. I am not receiving compensation for it (other than from Seeking Alpha). I have no business relationship with any company whose stock is mentioned in this article.
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Updated February 24, 2017 14:05:37
Graziers in central Queensland have cloned a prize cow, moving the technology from the lab to the paddock.
Owner of the new cloned calf, Bill Geddes, said the technology was becoming more viable for everyday producers and more graziers were using it.
Born via caesarean one week ago, Dasha was created by Richard Fry, of Clone International in Victoria.
He used a method called nuclear transfer, and his creation is the exact genetic copy of a cow from the Brangus breed (a cross between an Angus and a Brahman).
Mr Geddes said the decision to create a cloned calf rather than naturally breed an animal was made in an attempt to preserve the grey-colouring and Angus bloodline of the original Brangus cow.
"Over the years, we've bred quite a lot of calves from this old cow, and been able to breed her a number of different ways," he said.
"With the knowledge of what we've got and what we've bred, we thought it'd be a great opportunity to clone her, then breed from the new [cow], with the knowledge we learned from the old cow."
The Brangus's skin samples were taken to Melbourne and grown as embryos, before being impregnated through IVF into a recipient mother.
Of the 12 embryos implanted, only one survived, and went on to become Dasha.
"The percentage rate is always very low with the clones," Mr Geddes said.
"If you get one, you're very lucky and we got one."
Mr Geddes said he could see the potential for cloning in other areas of the commercial production cattle industry and he would not be surprised if the practice became more common.
He said there was great value in being able to re-create an animal after it had been processed through the abattoir and its full potential was known.
"With the [ability to] clone, they could slaughter the animal, find the one really good bull, and still be able to clone and breed from it," Mr Geddes said.
After the success of his first cloned calf on the property, Mr Geddes said he would definitely consider cloning in the future.
"You'd have to have an exceptional purpose to do it because it's quite expensive you wouldn't do it for practice," he said.
Topics: beef-cattle, cloning, rural, livestock, rockhampton-4700, vic
First posted February 24, 2017 08:39:00
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Another cloning success shows technology being used by everyday graziers - ABC Online
By George Seidel, Colorado State University
Its been 20 years since scientists in Scotland told the world about Dolly the sheep, the first mammal successfully cloned from an adult body cell. What was special about Dolly is that her parents were actually a single cell originating from mammary tissue of an adult ewe. Dolly was an exact genetic copy of that sheep a clone.
Dolly captured peoples imaginations, but those of us in the field had seen her coming through previous research. Ive been working with mammalian embryos for over 40 years, with some work in my lab specifically focusing on various methods of cloning cattle and other livestock species. In fact, one of the coauthors of the paper announcing Dolly worked in our laboratory for three years prior to going to Scotland to help create the famous clone.
Dolly was an important milestone, inspiring scientists to continue improving cloning technology as well as to pursue new concepts in stem cell research. The endgame was never meant to be armies of genetically identical livestock: Rather, researchers continue to refine the techniques and combine them with other methods to turbocharge traditional animal breeding methods as well as gain insights into aging and disease.
Dolly was a perfectly normal sheep who became the mother of numerous normal lambs. She lived to six and a half years, when she was eventually put down after a contagious disease spread through her flock, infecting cloned and normally reproduced sheep alike. Her life wasnt unusual; its her origin that made her unique.
Before the decades of experiments that led to Dolly, it was thought that normal animals could be produced only by fertilization of an egg by a sperm. Thats how things naturally work. These germ cells are the only ones in the body that have their genetic material all jumbled up and in half the quantity of every other kind of cell. That way when these so-called haploid cells come together at fertilization, they produce one cell with the full complement of DNA. Joined together, the cell is termed diploid, for twice, or double. Two halves make a whole.
From that moment forward, nearly all cells in that body have the same genetic makeup. When the one-cell embryo duplicates its genetic material, both cells of the now two-cell embryo are genetically identical. When they in turn duplicate their genetic material, each cell at the four-cell stage is genetically identical. This pattern goes on so that each of the trillions of cells in an adult is genetically exactly the same whether its in a lung or a bone or the blood.
In contrast, Dolly was produced by whats called somatic cell nuclear transfer. In this process, researchers remove the genetic material from an egg and replace it with the nucleus of some other body cell. The resulting egg becomes a factory to produce an embryo that develops into an offspring. No sperm is in the picture; instead of half the genetic material coming from a sperm and half from an egg, it all comes from a single cell. Its diploid from the start.
Dolly was the culmination of hundreds of cloning experiments that, for example, showed diploid embryonic and fetal cells could be parents of offspring. But there was no way to easily know all the characteristics of the animal that would result from a cloned embryo or fetus. Researchers could freeze a few of the cells of a 16-cell embryo, while going on to produce clones from the other cells; if a desirable animal was produced, they could thaw the frozen cells and make more copies. But this was impractical because of low success rates.
Dolly demonstrated that adult somatic cells also could be used as parents. Thus, one could know the characteristics of the animal being cloned.
By my calculations, Dolly was the single success from 277 tries at somatic cell nuclear transfer. Sometimes the process of cloning by somatic cell nuclear transfer still produces abnormal embryos, most of which die. But the process has greatly improved so success rates now are more like 10 percent; its highly variable, though, depending on the cell type used and the species.
More than 10 different cell types have been used successfully as parents for cloning. These days most cloning is done using cells obtained by biopsying skin.
Genetics is only part of the story. Even while clones are genetically identical, their phenotypes the characteristics they express will be different. Its like naturally occurring identical twins: They share all their genes but theyre not really exactly alike, especially if reared in different settings.
Environment plays a huge role for some characteristics. Food availability can influence weight. Diseases can stunt growth. These kinds of lifestyle, nutrition or disease effects can influence which genes are turned on or off in an individual; these are called epigenetic effects. Even though all the genetic material may be the same in two identical clones, they might not be expressing all the same genes.
Consider the practice of cloning winning racehorses. Clones of winners sometimes also will be winners but most of the time theyre not. This is because winners are outliers; they need to have the right genetics, but also the right epigenetics and the right environment to reach that winning potential. For example, one can never exactly duplicate the uterine conditions a winning racehorse experienced when it was a developing fetus. Thus, cloning champions usually leads to disappointment. On the other hand, cloning a stallion that sires a high proportion of race-winning horses will result very reliably in a clone that similarly sires winners. This is a genetic rather than a phenotypic situation.
Even though the genetics are reliable, there are aspects of the cloning procedure that mean the epigenetics and environment are suboptimal. For example, sperm have elegant ways of activating the eggs they fertilize00071-4/abstract), which will die unless activated properly; with cloning, activation usually is accomplished by a strong electric shock. Many of the steps of cloning and subsequent embryonic development are done in test tubes in incubators. These conditions are not perfect substitutes for the female reproductive tract where fertilization and early embryonic development normally occur.
Sometimes abnormal fetuses develop to term, resulting in abnormalities at birth. The most striking abnormal phenotype of some clones is termed large offspring syndrome, in which calves or lambs are 30 or 40 percent larger than normal, resulting in difficult birth. The problems stem from an abnormal placenta30217-5/abstract). At birth, these clones are genetically normal, but are overly large, and tend to be hyperinsulinemic and hypoglycemic. (The conditions normalize over time once the offspring is no longer influenced by the abnormal placenta.)
Recent improvements in cloning procedures have greatly reduced these abnormalities, which also occur with natural reproduction, but at a much lower incidence.
Many thousands of cloned mammals have been produced in nearly two dozen species. Very few of these concern practical applications, such as cloning a famous Angus bull named Final Answer (who recently died at an old age) in order to produce more high-quality cattle via his clones sperm.
But the cloning research landscape is changing fast. The driving force for producing Dolly was not to produce genetically identical animals. Rather researchers want to combine cloning techniques with other methods in order to efficiently change animals genetically much quicker than traditional animal breeding methods that take decades to make changes in populations of species such as cattle.
One recent example is introducing the polled (no horns) gene into dairy cattle, thus eliminating the need for the painful process of dehorning. An even more striking application has been to produce a strain of pigs that is incapable of being infected by the very contagious and debilitating PRRS virus. Researchers have even made cattle that cannot develop Mad Cow Disease. For each of these procedures, somatic cell nuclear transplantation is an essential part of the process.
To date, the most valuable contribution of these somatic cell nuclear transplantation experiments has been the scientific information and insights gained. Theyve enhanced our understanding of normal and abnormal embryonic development, including aspects of aging, and more. This information is already helping reduce birth defects, improve methods of circumventing infertility, develop tools to fight certain cancers and even decrease some of the negative consequences of aging in livestock and even in people. Two decades since Dolly, important applications are still evolving.
George Seidel, Professor of Biomedical Sciences, Colorado State University.
This article was originally published on The Conversation. Read the original article.
Photos via Belkorin, AP Photo/Darron Cummings, AP Photo/Thomas Terry, Getty Images / Jeff J Mitchell
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Twenty years ago today, the worlds first clone made from the cells of an adult mammal made her public debut. Dolly, a Finn Dorset sheep, was introduced to the public in 1997 after scientists at the Roslin Institute at the University of Edinburgh in Scotland implanted the cell nucleus from a sheep into an egg that was subsequently fertilized to create a clone.
Dollys debut set off a firestorm about both the practical value and ethics of cloning, including the possibility of human cloning. Currently, more than 40 countries including the UK, France, Germany and Japan formally ban human cloning. In other countries, including the U.S. and China, there is no legal prohibition on it.
On the anniversary of Dollys unveiling, here are five noteworthy findings about cloning and public opinion:
1 No one has ever cloned ahuman being, though scientists have cloned animals other than Dolly, including dogs, pigs, cows, horses and cats. Part of the reason is that cloning can introduce profound genetic errors, which can result in early and painful death. At the same time, labs in a variety of countries have successfully cloned human embryos for the purpose of producing stem cells that can be used in medical therapies.
2 Eight-in-ten American adults (81%) say cloning a human being is not morally acceptable, according to a May 2016 Gallup poll. There has been overwhelming opposition to human cloning since 2001. Just 13% of adults in 2016 say cloning is morally acceptable.
3 Americans are divided as to whether humans will be cloned in the near future. In a 2010 Pew Research Center survey, 48% of adults said that a human being would definitely or probably be cloned by 2050, compared with 49% who said such an event would not happen.
4 The public is divided about the prospect of using cloning to bring back to life species of animals that are currently extinct, such as the carrier pigeon or even the woolly mammoth. While bringing back dinosaurs, la Jurassic Park, might not possible due to the fact that dinosaurs have been dead for tens of millions of years, scientists could conceivably use fresher tissue samples to bring back more recently extinct species. In a 2013 Pew Research Center poll, half of all adults surveyed (50%) said that by 2050 researchers will be able to use cloning to bring back extinct species, with 48% predicting such a development wont occur.
5 Fewer Americans are concerned with cloning animals than with the prospect of cloning humans, according to the same 2016 Gallup survey. Still, a majority of adults (60%) say cloning animals like Dolly is morally wrong, compared with 34% who say its morally acceptable. Since 2001, there has been little to no change in these numbers.
Topics: Emerging Technology Impacts, Religion and Society, Religious Beliefs and Practices, Science and Innovation
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20 years after Dolly the sheep's debut, Americans remain skeptical of cloning - Pew Research Center
BBC News | Reviving woolly mammoths will take more than two years BBC News In 1996, Dolly the sheep became the first mammal to be cloned from an adult cell. Many different mammalian species have since been cloned, but the elephant is not among them. Cloning research suggests that, just because it is possible to clone one type ... |
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Reviving woolly mammoths will take more than two years - BBC News
Its been 20 years since scientists in Scotland told the world about Dolly the sheep, the first mammal successfully cloned from an adult body cell. What was special about Dolly is that her parents were actually a single cell originating from mammary tissue of an adult ewe. Dolly was an exact genetic copy of that sheepa clone.
Dolly captured peoples imaginations, but those of us in the field had seen her coming through previous research. Ive been working with mammalian embryos for over 40 years, with some work in my lab specifically focusing on various methods of cloning cattle and other livestock species. In fact, one of the coauthors of the paper announcing Dolly worked in our laboratory for three years prior to going to Scotland to help create the famous clone.
Dolly was an important milestone, inspiring scientists to continue improving cloning technology as well as to pursue new concepts in stem cell research. The endgame was never meant to be armies of genetically identical livestock.Rather, researchers continue to refine the techniques and combine them with other methods to turbocharge traditional animal breeding methods as well as gain insights into aging and disease.
Dolly was a perfectly normal sheep who became the mother of numerous normal lambs. She lived to six and a half years, when she was eventually put down after a contagious disease spread through her flock, infecting cloned and normally reproduced sheep alike. Her life wasnt unusual; its her origin that made her unique.
Before the decades of experiments that led to Dolly, it was thought that normal animals could be produced only by fertilization of an egg by a sperm. Thats how things naturally work. These germ cells are the only ones in the body that have their genetic material all jumbled up and in half the quantity of every other kind of cell. That way when these so-called haploid cells come together at fertilization, they produce one cell with the full complement of DNA. Joined together, the cell is termed diploid, for twice, or double. Two halves make a whole.
From that moment forward, nearly all cells in that body have the same genetic makeup. When the one-cell embryo duplicates its genetic material, both cells of the now two-cell embryo are genetically identical. When they in turn duplicate their genetic material, each cell at the four-cell stage is genetically identical. This pattern goes on so that each of the trillions of cells in an adult is genetically exactly the samewhether its in a lung or a bone or the blood.
In contrast, Dolly was produced by whats called somatic cell nuclear transfer. In this process, researchers remove the genetic material from an egg and replace it with the nucleus of some other body cell. The resulting egg becomes a factory to produce an embryo that develops into an offspring. No sperm is in the picture.Instead of half the genetic material coming from a sperm and half from an egg, it all comes from a single cell. Its diploid from the start.
Dolly was the culmination of hundreds of cloning experiments that, for example, showed diploid embryonic and fetal cells could be parents of offspring. But there was no way to easily know all the characteristics of the animal that would result from a cloned embryo or fetus. Researchers could freeze a few of the cells of a 16-cell embryo, while going on to produce clones from the other cells. If a desirable animal was produced, they could thaw the frozen cells and make more copies. But this was impractical because of low success rates.
Dolly demonstrated that adult somatic cells also could be used as parents. Thus, one could know the characteristics of the animal being cloned.
By my calculations, Dolly was the single success from 277 tries at somatic cell nuclear transfer. Sometimes the process of cloning by somatic cell nuclear transfer still produces abnormal embryos, most of which die. But the process has greatly improved so success rates now are more like 10 percent; its highly variable, though, depending on the cell type used and the species.
More than 10 different cell types have been used successfully as parents for cloning. These days most cloning is done using cells obtained by biopsying skin.
Genetics is only part of the story. Even while clones are genetically identical, their phenotypesthe characteristics they expresswill be different. Its like naturally occurring identical twins: They share all their genes but theyre not really exactly alike, especially if reared in different settings.
Environment plays a huge role for some characteristics. Food availability can influence weight. Diseases can stunt growth. These kinds of lifestyle, nutrition, or disease effects can influence which genes are turned on or off in an individual; these are called epigenetic effects. Even though all the genetic material may be the same in two identical clones, they might not be expressing all the same genes.
Consider the practice of cloning winning racehorses. Clones of winners sometimes also will be winnersbut most of the time theyre not. This is because winners are outliers. They need to have the right genetics, but also the right epigenetics and the right environment to reach that winning potential. For example, one can never exactly duplicate the uterine conditions a winning racehorse experienced when it was a developing fetus. Thus, cloning champions usually leads to disappointment. On the other hand, cloning a stallion that sires a high proportion of race-winning horses will result very reliably in a clone that similarly sires winners. This is a genetic rather than a phenotypic situation.
Even though the genetics are reliable, there are aspects of the cloning procedure that mean the epigenetics and environment are suboptimal. For example, sperm have elegant ways of activating the eggs they fertilize, which will die unless activated properly. With cloning, activation usually is accomplished by a strong electric shock. Many of the steps of cloning and subsequent embryonic development are done in test tubes in incubators. These conditions are not perfect substitutes for the female reproductive tract where fertilization and early embryonic development normally occur.
Sometimes abnormal fetuses develop to term, resulting in abnormalities at birth. The most striking abnormal phenotype of some clones is termed large offspring syndrome, in which calves or lambs are 30 or 40 percent larger than normal, resulting in difficult birth. The problems stem from an abnormal placenta. At birth, these clones are genetically normal, but are overly large, and tend to be hyperinsulinemic and hypoglycemic. (The conditions normalize over time once the offspring is no longer influenced by the abnormal placenta.)
Recent improvements in cloning procedures have greatly reduced these abnormalities, which also occur with natural reproduction, but at a much lower incidence.
Many thousands of cloned mammals have been produced in nearly two dozen species. Very few of these concern practical applications, such as cloning a famous Angus bull named Final Answer (who recently died at an old age) in order to produce more high-quality cattle via his clones sperm.
But the cloning research landscape is changing fast. The driving force for producing Dolly was not to produce genetically identical animals. Rather, researchers want to combine cloning techniques with other methods in order to efficiently change animals geneticallymuch quicker than traditional animal breeding methods that take decades to make changes in populations of species such as cattle.
One recent example is introducing the polled (no horns) gene into dairy cattle, thus eliminating the need for the painful process of dehorning. An even more striking application has been to produce a strain of pigs that is incapable of being infected by the very contagious and debilitating PRRS virus. Researchers have even made cattle that cannot develop Mad Cow Disease. For each of these procedures, somatic cell nuclear transplantation is an essential part of the process.
To date, the most valuable contribution of these somatic cell nuclear transplantation experiments has been the scientific information and insights gained. Theyve enhanced our understanding of normal and abnormal embryonic development, including aspects of aging, and more. This information is already helping reduce birth defects, improve methods of circumventing infertility, develop tools to fight certain cancers, and even decrease some of the negative consequences of agingin livestock and even in people. Two decades since Dolly, important applications are still evolving.
George Seidel, professor of biomedical sciences, Colorado State University
This article was originally published on The Conversation. Read the original article.
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First, it was Facebook-owned Instagram. Now it is WhatsApp, another company controlled by Marck Zuckerberg. It's safe to say that Facebook is very fond of Evan Spiegel's soon-to-list unicorn and social media darling, Snapchat. In August, Instagram copied Snapchats popular Stories feature.
Now, WhatsApp has gone ahead and done the same. Stories is essentially a feature wherein one can share photos, videos for up to 24 hours before they disappear altogether. Furthermore, WhatsApp has allowed people to add GIFs into their Stories. The format that Snapchat invented is now becoming universal.
Stories is essentially a feature wherein one can share photos, videos for up to 24 hours before they disappear altogether. Furthermore, WhatsApp has allowed people to add GIFs into their Stories. The format that Snapchat invented is now becoming universal.
WhatsApp on Monday, 20 February, unveiled a new version of its existing plain status update simply calling it WhatsApp Status to its 1.2 billion users. Previously, one could only share a short message like, "out to lunch" or "gone to the doctor's" or maybe even something philosophical. Who knows, at the rate, they are going, Facebook might just be next. In fact, Facebook's Messenger product was revamped in December, to make sending photos a the forefront. At least Facebook hasn't made the camera the first thing that people see when the app opens.
WhatsApp though does stand out from the crowd. It added the abilities to add GIFs to Status'. They've even gone and made sure that all status updates are end-to-end encrypted (disappear means disappear). Unlike Snapchat and Instagram, WhatsApp videos can be as long as 45 seconds - a welcome addition. Also, WhatsApp status' are shared only with those in your address book and not others.
This is a format that is being broadly adopted, and were adopting it as well, product manager at WhatsApp, Randall Sarafa, told Recode. There are some pretty interesting things that weve done to make it unique to WhatsApp. Remember, Facebook had offered Spiegel $3 billion to buy Snapchat back in 2013 but that offer was turned down.
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Facebook does it again. WhatsApp launches revamped Status, cloning Snapchat - Catch News
Cloning, to some a glimpse of the future, to others a step too far. There can be no doubt, however, that this technology will have important ramifications for your future, for illor good no one can yet tell. Cloned steaks are currently available on supermarket shelves but cloning is nothing new. Animals have been cloned since 1885 when Hans Adolf Edward Dreisch cloned a sea urchin. Cloning may well be the saving grace for many an endangered species. If you believe inconspiracy theorieshumans have either already been cloned. There can, however, be no doubt that this is inevitable in the not too distant future.
In the mean-time, we will happily be consuming cloned meat, which in the US doesnt require producers to label as such. Lets have a look at fifteen animals that have been successfully cloned. The following list is not exhaustive and merely a selection of interesting examples for your pleasure. Youre welcome.
An Asian carp was successfully cloned in 1963 and a mere decade later Tong Dizhou also cloned a European crucian carp. We often think of cloning as a modern development so excusing the 1885 example this is actually amazing.
Perhaps the most famous of all cloned animals, Dolly was created artificially in 1996. Dolly lived to the grand old age of six. She was the first cloned mammal and to this day is considered a great success. There have been many versions of Dolly since, which is a little perturbing. The author has fond memories of first hearing of this breakthrough during his formative teenage years.
This cheeky little rodent was cloned in Hawaii in 1997. Unsurprisingly, Cumulima was the first successfully cloned mouse. She lived until the ripe old age of two years and seven months. This was a great achievement for her creators. She produced two litters and was, ahem, later retired.
The Japanese were quite prolific during the 90s and their cloning program. These two cows were created in 1998 and have subsequently been duplicated several thousand times since. Noto and Kaga have paved the way for many other clones engineered to produce improved meat and milk products.
Another example of a cloned ruminant, Mira was cloned in 1998. Mira and her sisters were created in a US lab as predecessors of livestock engineering for the pharmaceutical industry.
This family of clones, if an accurate collective term for clones, were created for modification to allow for human cell and organ transplant. Millie and her copies were created in 2000 by a US based company.
Ombretta is a great example of cloning for the good. Before Ombretta, Mouflon were an endangered species until, of course, 2001 when this species was brought back from the brink of extinction. This was a great example of how surrogacy can help to produce a viable clone of endangered species. Thanks, Ombretta.
The lab monkey world received its first clone in 2000. US-based Tetra is the first in a series of cloned monkeys that scientists could use as test subjects to learn more about diseases like diabetes.
Guar what now? A Guar is an Asian ox that has been dwindling in numbers. Thankfully, they were succesfully cloned in 2001. Sadly, Noah lived for two days and died of dysentery soon after.
Copy Cat could well be the starting gun for an entirely new industry of pet clones. Created in 2001 Copy Cat, was, well, a domestic cat. Copy Cat was the worlds first cloned pet.
Given the never-ending game of cat and, ahem, rat it is only fair to include Ralph. Ralph was one, or is it legion, of three rat pups created in 2002. Ralphs genetic makeup may well be used in research labs in the future. 129 embryos were implanted into two female rats with three being viable rats. Ok, so not a legion of rats, but it sounded cool ok? Is is just me who believes that rats arent exactly in need of cloning technology?
Mules are sterile right? Not if you clone them! Well yes, they are still sterile but this is a great way of sticking your middle finger up to biological boundaries. Idaho Gem was born in 2003.
No, not Prometheus damn your devious mindunless, well actually yes if you can speak Greek, of course. An Italian team created this cloned horse in 2003. The belief was that they could mass produce Italian stallions. Sadly the experiment failed. She was birthed by her own clone source parent.
Being endangered is not a prerequisite of cloning potential. The African Wildcat was cloned for no other reason than we just can. US scientists used Ditteaux as a template for cloning other, more vulnerable animals.
Who doesnt like ferrets? Surely if any animal was worthy of replication its these furry, limbed bitty snake beasts? Ok, I might be a bit biased. Libby and Lilly were cloned in 2004. But why? As it turns out, ferrets are useful for the study of human respiratory diseases. They are still nasty bitty furry snake monsters, however. They also smell of pee.
Sources:businesspundit.com
[Featured Image Source: PublicDomainPictures via Pixabay]
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15 Animals That Have Been Successfully Cloned by Scientists - Interesting Engineering
February 20, 2017 by Jos Cibelli, The Conversation More Dollies, cloned from the same cell line. Credit: Kevin Sinclair, University of Nottingham, CC BY-ND
In 1997 Dolly the sheep was introduced to the world by biologists Keith Campbell, Ian Wilmut and colleagues. Not just any lamb, Dolly was a clone. Rather than being made from a sperm and an egg, she originated from a mammary gland cell of another, no-longer-living, six-year-old Fynn Dorset ewe.
With her birth, a scientific and societal revolution was also born.
Some prominent scientists raised doubts; it was too good to be true. But more animals were cloned: first the laboratory mouse, then cows, goats, pigs, horses, even dogs, ferrets and camels. By early 2000, the issue was settled: Dolly was real and cloning adults was possible.
The implications of cloning animals in our society were self-evident from the start. Our advancing ability to reprogram adult, already specialized cells and start them over as something new may one day be the key to creating cells and organs that match the immune system of each individual patient in need of replacements.
But what somehow got lost was the fact that a clone was born at day zero created from the cell of another animal that was six years old. Researchers have spent the past 20 years trying to untangle the mysteries of how clones age. How old, biologically, are these animals born from other adult animals' cells?
Decades of cloning research
Dolly became an international celebrity, but she was not the first vertebrate to be cloned from a cell taken from the body of another animal. In 1962, developmental biologist John Gurdon cloned the first adult animal by taking a cell from the intestine of one frog and injecting it into an egg of another. Gurdon's work did not go unnoticed he went on to share the 2012 Nobel Prize in Physiology or Medicine. But it was Dolly who had captured our imagination. Was it because she was a warm-blooded animal, a mammal, much closer to human? If you could do it in a sheep, you could do it on us!
Dolly, along with Gurdon's frogs from 35 years earlier and all the other experiments in between, redirected our scientific studies. It was amazing to see a differentiated cell an adult cell specialized to do its particular job transform into an embryonic one that could go on to give rise to all the other cells of a normal body. We researchers wondered if we could go further: Could we in the lab make an adult cell once again undifferentiated, without needing to make a cloned embryo?
A decade after Dolly was announced, stem cell researcher Shynia Yamanaka's team did just that. He went on to be the Nobel corecipient with Gurdon for showing that mature cells could be reprogrammed to become pluripotent: able to develop into any specialized adult cell.
Now we have the possibility of making individualized replacement cells potentially any kind to replace tissue damaged due to injury, genetic disorders and degeneration. Not only cells; we may soon be able to have our own organs grown in a nonhuman host, ready to be transplanted when needed.
If Dolly was responsible for unleashing the events that culminate with new methods of making fully compatible cells and organs, then her legacy would be to improve the health of practically all human beings on this planet. And yet, I am convinced that there are even better things to come.
Dolly's secrets still unfolding
In the winter of 2013, I found myself driving on the wrong side of the road through the Nottingham countryside. In contrast to the luscious landscape, I was in a state gloom; I was on my way to see Keith Campbell's family after his sudden death a few weeks earlier. Keith was a smart, fun, loving friend who, along with Ian Wilmut and colleagues at the Roslin Institute, had brought us Dolly 15 years earlier. We had met at a conference in the early 1990s, when we were both budding scientists playing around with cloning, Keith with sheep, me with cows. An extrovert by nature, he quickly dazzled me with his wit, self-deprecating humor and nonstop chat, all delivered in a thick West Midlands accent. Our friendship that began then continued until his death.
When I knocked at the door of his quaint farmhouse, my plan was to stay just a few minutes, pay my respects to his wife and leave. Five hours and several Guinnesses later, I left feeling grateful. Keith could do that to you, but this time it wasn't him, it was his latest work speaking for him. That's because his wife very generously told me the project Keith was working on at the time of his death. I couldn't hide my excitement: Could it be possible that after 20 years, the most striking aspect of Dolly's legacy was not yet revealed?
See, when Dolly was cloned, she was created using a cell from a six-year-old sheep. And she died at age six and a half, a premature death for a breed that lives an average of nine years or more. People assumed that an offspring cloned from an adult was starting at an age disadvantage; rather than truly being a "newborn," it seemed like a clone's internal age would be more advanced that the length of its own life would suggest. Thus the notion that clones' biological age and their chronological one were out of sync, and that "cloned animals will die young."
Some of us were convinced that if the cloning procedure was done properly, the biological clock should be reset a newborn clone would truly start at zero. We worked very hard to prove our point. We were not convinced by a single DNA analysis done in Dolly showing slightly shorter telomeres the repetitive DNA sequences at the end of chromosomes that "count" how many times a cell divides. We presented strong scientific evidence showing that cloned cows had all the same molecular signs of aging as a nonclone, predicting a normal lifespan. Others showed the same in cloned mice. But we couldn't ignore reports from colleagues interpreting biological signs in cloned animals that they attributed to incomplete resetting of the biological clock. So the jury was out.
Aging studies are very hard to do because there are only two data points that really count: date of birth and date of death. If you want to know the lifespan of an individual you have to wait until its natural death. Little did I know, that is what Keith was doing back in 2012.
That Saturday afternoon I spent in Keith's house in Nottingham, I saw a photo of the animals in Keith's latest study: several cloned Dollies, all much older than Dolly at the time she had died, and they looked terrific. I was in awe.
The data were confidential, so I had to remain silent until late last year when the work was posthumously published. Keith's coauthors humbly said: "For those clones that survive beyond the perinatal period [] the emerging consensus, supported by the current data, is that they are healthy and seem to age normally."
These findings became even more relevant when last December researchers at the Scripps Research Institute found that induced pluripotent stem cells reprogrammed using the "Yamanaka factors" retain the aging epigenetic signature of the donor individual. In other words, using these four genes to attempt to reprogram the cells does not seem to reset the biological clock.
The new Dollies are now telling us that if we take a cell from an animal of any age, and we introduce its nucleus into a nonfertilized mature egg, we can have an individual born with its lifespan fully restored. They confirmed that all signs of biological and chronological age matched between cloned and noncloned sheep.
There seems to be a natural built-in mechanism in the eggs that can rejuvenate a cell. We don't know what it is yet, but it is there. Our group as well as others are hard at work, and as soon as someone finds it, the most astonishing legacy of Dolly will be realized.
Explore further: How much do you know about Dolly the Sheep?
This article was originally published on The Conversation. Read the original article.
This week marked the 20th anniversary of the birth of arguably the most famous sheep that ever chewed grass. Dolly was created at The Roslin Institute, Scotland, which receives long-term strategic funding from BBSRC.
It's now 20 years since the birth of Dolly the sheep, the first mammal to be cloned. This groundbreaking scientific achievement was accompanied by warnings that Dolly might age prematurely because she had been cloned from ...
(AP)Keith Campbell, a prominent biologist who worked on cloning Dolly the sheep, has died at 58, the University of Nottingham said Thursday.
Three weeks after the scientific world marked the 20th anniversary of the birth of Dolly the sheep new research, published by The University of Nottingham, in the academic journal Nature Communications has shown that four ...
There's a three- or four-way dispute among British scientists about who deserves the credit for Dolly, the first cloned sheep.
A petition has called on Britain's Queen Elizabeth II to take away the knighthood she bestowed on Ian Wilmut for his cloning of the sheep Dolly.
Forest elephant populations in one of Central Africa's largest and most important preserves have declined between 78 percent and 81 percent because of poaching, a new Duke University-led study finds.
The winter habits of Britain's basking sharks have been revealed for the first time.
What looks like a caterpillar chewing on a leaf or a beetle consuming fruit is likely a three-way battle that benefits most, if not all of the players involved, according to a Penn State entomologist.
By tagging individual bumblebees with microchips, biologists have gained insights into the daily life of a colony of bumblebees (Bombus impatiens) in unprecedented detail. The team found that while most bees are generalists ...
Climate change from political and ecological standpoints is a constant in the media and with good reason, said a Texas A&M AgriLife Research scientist, but proof of its impact is sometimes found in unlikely places.
At what point on the journey along the branches of the evolutionary tree does a population become its own, unique species? And is a species still distinct, if it mates with a different, but closely related species? Evolutionary ...
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More lessons from Dolly the sheepis a clone really born at age ... - Phys.Org
Good morning! This week were delving into longreads on the present and future of women, the groundwork for Trump, andcloning? Follow us down the rabbit hole, please drop your favourite reads of the week in comments, and stay tuned this week, because we have an exciting announcement coming up!
Some of the most astute predictions about the rise of Trump came not from leftist visionaries, but sharp conservative thinkers which is perhaps a sharp reminder that reading conservatives can provide valuable insight into preventable situations.
But unlike the old kind of populism that struck terror in the hearts of the Founding Fathers, the new populism, as Kristol dubbed it, was nothing to worry about. In his view, the sentiments of the people now represented a common sense reaction against the un-wisdom of the elites. What was needed, he believed, was a strong leader who could rally the masses to reclaim American democracy from the clutches of liberal intellectuals, institute a faith-based government, and bind the nation together by preaching an assertive nationalism.
Women militants are often dismissed, belittled, or treated as secondary to their male counterparts. Society rarely allows women to respond to oppression with violence, to consider violence as a rational and reasonable reaction, and Ensler challenges this notion through conversations with women fighters.
I have interviewed women guerillas in the mountains of the Philippines and the indigenous Lumads fighting back against the mining corporations stealing and poisoning their lands, women in US prisons involved in the Black Liberation movement in the US imprisoned for violent acts. It is clear in joining militant movements that women escaped traditional oppressive gender role assignments in every society. Every woman I spoke to talked about rage, rage and helplessness in the face of state power. For them, becoming an armed militant was a way of expressing political outrage and not being rolled over by the neoliberal, racist, capitalist patriarchy. It was a way of keeping dignity and fighting for their families and land and traditions and life itself. It was a way of surviving.
The social contract that governs our conduct is faded, disrupted, chaotic. What does that mean for the way we interact with each other, and the world? Can we reclaim an age of manners?
The social code remains unwritten, and it has always interested me how many problems this poses in the matter of ascertaining the truth. The truth often appears in the guise of a threat to the social code. It has this in common with rudeness. When people tell the truth, they can experience a feeling of release from pretense that is perhaps similar to the release of rudeness. It might follow that people can mistake truth for rudeness, and rudeness for truth. It may only be by examining the aftermath of each that it becomes possible to prove which was which.
The editorial team at Catapult are consistently developing some of my favourite longreads on a regular basis I stop by at least once a week for absolutely stunning work. This layered, complicated, lyrical piece about being a woman in a world that hates women is a superb read.
Now there is only one man in my office who will hold a conversation with me without looking self-conscious. We are at a happy hour after a work conference where we talk about being writers. The conversation means something to me; it is raining outside and the bar is crowded and loud and we have all come from the conference and I am happy to talk about the thing I love best. Then we talk about our office. It turns out that he knows the story already. It turns out everyone knows the story, just as I feared. Im so happy, I could kiss you right now. I drink. I drink so much that later I will have to walk past my car and keep walking. I ask, is it something, or is it nothing? He hates the boss, too. Everyone hates the boss, wants him out, wants this to be something.
I have a vivid memory of hearing a report about Dolly the sheep on Morning Edition and the series of conversations the earthshattering event sparked what would cloning mean for society? 20 years later, we still arent sure.
Instantly understandable to an excited Mrs WalkerI knew we had done what we had thought we had donethe fax had been kept terse and cryptic because the breakthrough was, at the time, hush-hush. The existence of Dolly the sheep would not be revealed to the world at large until the following February, when a scientific paper was published in Natureat which point a furore broke out that went far beyond the scientific world.
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Must reads: Populism, sexism, cloning, and rudeness - GlobalComment.com
Well hello, Dolly.
Its been 20 years since scientists in Scotland told the world about Dolly the sheep, the first mammal successfully cloned from an adult body cell. What was special about Dolly is that her parents were actually a single cell originating from mammary tissue of an adult ewe. Dolly was an exact genetic copy of that sheep a clone.
Dolly captured peoples imaginations, but those of us in the field had seen her coming through previous research. Ive been working with mammalian embryos for over 40 years, with some work in my lab specifically focusing on various methods of cloning cattle and other livestock species. In fact, one of the coauthors of the paper announcing Dolly worked in our laboratory for three years prior to going to Scotland to help create the famous clone.
Dolly was an important milestone, inspiring scientists to continue improving cloning technology as well as to pursue new concepts in stem cell research. The endgame was never meant to be armies of genetically identical livestock: Rather, researchers continue to refine the techniques and combine them with other methods to turbocharge traditional animal breeding methods as well as gain insights into aging and disease.
Dolly was a perfectly normal sheep who became the mother of numerous normal lambs. She lived to six and a half years, when she was eventually put down after a contagious disease spread through her flock, infecting cloned and normally reproduced sheep alike. Her life wasnt unusual; its her origin that made her unique.
Before the decades of experiments that led to Dolly, it was thought that normal animals could be produced only by fertilization of an egg by a sperm. Thats how things naturally work. These germ cells are the only ones in the body that have their genetic material all jumbled up and in half the quantity of every other kind of cell. That way when these so-called haploid cells come together at fertilization, they produce one cell with the full complement of DNA. Joined together, the cell is termed diploid, for twice, or double. Two halves make a whole.
From that moment forward, nearly all cells in that body have the same genetic makeup. When the one-cell embryo duplicates its genetic material, both cells of the now two-cell embryo are genetically identical. When they in turn duplicate their genetic material, each cell at the four-cell stage is genetically identical. This pattern goes on so that each of the trillions of cells in an adult is genetically exactly the same whether its in a lung or a bone or the blood.
In contrast, Dolly was produced by whats called somatic cell nuclear transfer. In this process, researchers remove the genetic material from an egg and replace it with the nucleus of some other body cell. The resulting egg becomes a factory to produce an embryo that develops into an offspring. No sperm is in the picture; instead of half the genetic material coming from a sperm and half from an egg, it all comes from a single cell. Its diploid from the start.
Dolly was the culmination of hundreds of cloning experiments that, for example, showed diploid embryonic and fetal cells could be parents of offspring. But there was no way to easily know all the characteristics of the animal that would result from a cloned embryo or fetus. Researchers could freeze a few of the cells of a 16-cell embryo, while going on to produce clones from the other cells; if a desirable animal was produced, they could thaw the frozen cells and make more copies. But this was impractical because of low success rates.
Dolly demonstrated that adult somatic cells also could be used as parents. Thus, one could know the characteristics of the animal being cloned.
By my calculations, Dolly was the single success from 277 tries at somatic cell nuclear transfer. Sometimes the process of cloning by somatic cell nuclear transfer still produces abnormal embryos, most of which die. But the process has greatly improved so success rates now are more like 10 percent; its highly variable, though, depending on the cell type used and the species.
More than 10 different cell types have been used successfully as parents for cloning. These days most cloning is done using cells obtained by biopsying skin.
Genetics is only part of the story. Even while clones are genetically identical, their phenotypes the characteristics they express will be different. Its like naturally occurring identical twins: They share all their genes but theyre not really exactly alike, especially if reared in different settings.
Environment plays a huge role for some characteristics. Food availability can influence weight. Diseases can stunt growth. These kinds of lifestyle, nutrition or disease effects can influence which genes are turned on or off in an individual; these are called epigenetic effects. Even though all the genetic material may be the same in two identical clones, they might not be expressing all the same genes.
Consider the practice of cloning winning racehorses. Clones of winners sometimes also will be winners but most of the time theyre not. This is because winners are outliers; they need to have the right genetics, but also the right epigenetics and the right environment to reach that winning potential. For example, one can never exactly duplicate the uterine conditions a winning racehorse experienced when it was a developing fetus. Thus, cloning champions usually leads to disappointment. On the other hand, cloning a stallion that sires a high proportion of race-winning horses will result very reliably in a clone that similarly sires winners. This is a genetic rather than a phenotypic situation.
Even though the genetics are reliable, there are aspects of the cloning procedure that mean the epigenetics and environment are suboptimal. For example, sperm have elegant ways of activating the eggs they fertilize, which will die unless activated properly; with cloning, activation usually is accomplished by a strong electric shock. Many of the steps of cloning and subsequent embryonic development are done in test tubes in incubators. These conditions are not perfect substitutes for the female reproductive tract where fertilization and early embryonic development normally occur.
Sometimes abnormal fetuses develop to term, resulting in abnormalities at birth. The most striking abnormal phenotype of some clones is termed large offspring syndrome, in which calves or lambs are 30 or 40 percent larger than normal, resulting in difficult birth. The problems stem from an abnormal placenta. At birth, these clones are genetically normal, but are overly large, and tend to be hyperinsulinemic and hypoglycemic. (The conditions normalize over time once the offspring is no longer influenced by the abnormal placenta.)
Recent improvements in cloning procedures have greatly reduced these abnormalities, which also occur with natural reproduction, but at a much lower incidence.
Many thousands of cloned mammals have been produced in nearly two dozen species. Very few of these concern practical applications, such as cloning a famous Angus bull named Final Answer (who recently died at an old age) in order to produce more high-quality cattle via his clones sperm.
But the cloning research landscape is changing fast. The driving force for producing Dolly was not to produce genetically identical animals. Rather researchers want to combine cloning techniques with other methods in order to efficiently change animals genetically much quicker than traditional animal breeding methods that take decades to make changes in populations of species such as cattle.
One recent example is introducing the polled (no horns) gene into dairy cattle, thus eliminating the need for the painful process of dehorning. An even more striking application has been to produce a strain of pigs that is incapable of being infected by the very contagious and debilitating PRRS virus. Researchers have even made cattle that cannot develop Mad Cow Disease. For each of these procedures, somatic cell nuclear transplantation is an essential part of the process.
To date, the most valuable contribution of these somatic cell nuclear transplantation experiments has been the scientific information and insights gained. Theyve enhanced our understanding of normal and abnormal embryonic development, including aspects of aging, and more. This information is already helping reduce birth defects, improve methods of circumventing infertility, develop tools to fight certain cancers and even decrease some of the negative consequences of aging in livestock and even in people. Two decades since Dolly, important applications are still evolving.
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20 years after Dolly: Everything you always wanted to know about ... - The Conversation US
Its been 20 years since scientists in Scotland told the world about Dolly the sheep, the first mammal successfully cloned from an adult body cell. What was special about Dolly is that her parents were actually a single cell originating from mammary tissue of an adult ewe. Dolly was an exact genetic copy of that sheep a clone.
Dolly captured peoples imaginations, but those of us in the field had seen her coming through previous research. Ive been working with mammalian embryos for over 40 years, with some work in my lab specifically focusing on various methods of cloning cattle and other livestock species. In fact, one of the coauthors of the paper announcing Dolly worked in our laboratory for three years prior to going to Scotland to help create the famous clone.
Dolly was an important milestone, inspiring scientists to continue improving cloning technology as well as to pursue new concepts in stem cell research. The endgame was never meant to be armies of genetically identical livestock: Rather, researchers continue to refine the techniques and combine them with other methods to turbocharge traditional animal breeding methods as well as gain insights into aging and disease.
Not the usual sperm + egg Dolly was a perfectly normal sheep who became the mother of numerous normal lambs. She lived to six and a half years, when she was eventually put down after a contagious disease spread through her flock, infecting cloned and normally reproduced sheep alike. Her life wasnt unusual; its her origin that made her unique.
Before the decades of experiments that led to Dolly, it was thought that normal animals could be produced only by fertilization of an egg by a sperm. Thats how things naturally work. These germ cells are the only ones in the body that have their genetic material all jumbled up and in half the quantity of every other kind of cell. That way when these so-called haploid cells come together at fertilization, they produce one cell with the full complement of DNA. Joined together, the cell is termed diploid, for twice, or double. Two halves make a whole.
From that moment forward, nearly all cells in that body have the same genetic makeup. When the one-cell embryo duplicates its genetic material, both cells of the now two-cell embryo are genetically identical. When they in turn duplicate their genetic material, each cell at the four-cell stage is genetically identical. This pattern goes on so that each of the trillions of cells in an adult is genetically exactly the same whether its in a lung or a bone or the blood.
In contrast, Dolly was produced by whats called somatic cell nuclear transfer. In this process, researchers remove the genetic material from an egg and replace it with the nucleus of some other body cell. The resulting egg becomes a factory to produce an embryo that develops into an offspring. No sperm is in the picture; instead of half the genetic material coming from a sperm and half from an egg, it all comes from a single cell. Its diploid from the start.
Long research path led to Dolly Dolly was the culmination of hundreds of cloning experiments that, for example, showed diploid embryonic and fetal cells could be parents of offspring. But there was no way to easily know all the characteristics of the animal that would result from a cloned embryo or fetus. Researchers could freeze a few of the cells of a 16-cell embryo, while going on to produce clones from the other cells; if a desirable animal was produced, they could thaw the frozen cells and make more copies. But this was impractical because of low success rates.
Dolly demonstrated that adult somatic cells also could be used as parents. Thus, one could know the characteristics of the animal being cloned.
By my calculations, Dolly was the single success from 277 tries at somatic cell nuclear transfer. Sometimes the process of cloning by somatic cell nuclear transfer still produces abnormal embryos, most of which die. But the process has greatly improved so success rates now are more like 10 percent; its highly variable, though, depending on the cell type used and the species.
More than 10 different cell types have been used successfully as parents for cloning. These days most cloning is done using cells obtained by biopsying skin.
More than genes can affect a clone Genetics is only part of the story. Even while clones are genetically identical, their phenotypes the characteristics they express will be different. Its like naturally occurring identical twins: They share all their genes but theyre not really exactly alike, especially if reared in different settings.
Environment plays a huge role for some characteristics. Food availability can influence weight. Diseases can stunt growth. These kinds of lifestyle, nutrition or disease effects can influence which genes are turned on or off in an individual; these are called epigenetic effects. Even though all the genetic material may be the same in two identical clones, they might not be expressing all the same genes.
Consider the practice of cloning winning racehorses. Clones of winners sometimes also will be winners but most of the time theyre not. This is because winners are outliers; they need to have the right genetics, but also the right epigenetics and the right environment to reach that winning potential. For example, one can never exactly duplicate the uterine conditions a winning racehorse experienced when it was a developing fetus. Thus, cloning champions usually leads to disappointment. On the other hand, cloning a stallion that sires a high proportion of race-winning horses will result very reliably in a clone that similarly sires winners. This is a genetic rather than a phenotypic situation.
Even though the genetics are reliable, there are aspects of the cloning procedure that mean the epigenetics and environment are suboptimal. For example, sperm have elegant ways of activating the eggs they fertilize, which will die unless activated properly; with cloning, activation usually is accomplished by a strong electric shock. Many of the steps of cloning and subsequent embryonic development are done in test tubes in incubators. These conditions are not perfect substitutes for the female reproductive tract where fertilization and early embryonic development normally occur.
Sometimes abnormal fetuses develop to term, resulting in abnormalities at birth. The most striking abnormal phenotype of some clones is termed large offspring syndrome, in which calves or lambs are 30 or 40 percent larger than normal, resulting in difficult birth. The problems stem from an abnormal placenta. At birth, these clones are genetically normal, but are overly large, and tend to be hyperinsulinemic and hypoglycemic. (The conditions normalize over time once the offspring is no longer influenced by the abnormal placenta.)
Recent improvements in cloning procedures have greatly reduced these abnormalities, which also occur with natural reproduction, but at a much lower incidence.
Continuing onward with cloning Many thousands of cloned mammals have been produced in nearly two dozen species. Very few of these concern practical applications, such as cloning a famous Angus bull named Final Answer (who recently died at an old age) in order to produce more high-quality cattle via his clones sperm.
But the cloning research landscape is changing fast. The driving force for producing Dolly was not to produce genetically identical animals. Rather researchers want to combine cloning techniques with other methods in order to efficiently change animals genetically much quicker than traditional animal breeding methods that take decades to make changes in populations of species such as cattle.
One recent example is introducing the polled (no horns) gene into dairy cattle, thus eliminating the need for the painful process of dehorning. An even more striking application has been to produce a strain of pigs that is incapable of being infected by the very contagious and debilitating PRRS virus. Researchers have even made cattle that cannot develop Mad Cow Disease. For each of these procedures, somatic cell nuclear transplantation is an essential part of the process.
To date, the most valuable contribution of these somatic cell nuclear transplantation experiments has been the scientific information and insights gained. Theyve enhanced our understanding of normal and abnormal embryonic development, including aspects of aging, and more. This information is already helping reduce birth defects, improve methods of circumventing infertility, develop tools to fight certain cancers and even decrease some of the negative consequences of aging in livestock and even in people. Two decades since Dolly, important applications are still evolving.
Credit : Associated Press (AP)
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Antiquities Minister Khaled al-Anany and Luxor governor Mohamed Badr inaugurated on Friday the first center for cloning the tombs of Pharaonic kings and queens.
The officials inaugurated as well the Stoppelaere House near the Valley of the Kings, west of Luxor.
The Ambassador of Switzerland to Egypt, Markus Leitner, attended the inauguration.
An archaeological Egyptian source told DPA agency that the project was held in collaboration with the Spanish and Swiss governments and aims to train Egyptians on the uses of the three-dimentional survey and compound photography which are used in cloning pharaonic tombs such as King Tutankhamun's cloned tomb, which was constructed by Spanish Factum Arte Foundation.
The Center aims to implement two projects to clone King Seti the First's tomb in the Valley of the Kings, and the tomb of Queen Nefertari in the Valley of the Queens, so that tourists can visit the two imitated tombs in case the original ones are closed.
The two original archaeological tombs are periodically closed to protect their inscriptions.
Stoppelaere House belongs to deceased Italian restorer Alexandre Stoppelaere who was head of the Restoration Department of the Egyptian Antiquities Authority in the mid-20th century. It was designed and built by Egyptian architect Hassan Fathy in 1950.
The house will serve as headquarters for training Egyptian archaeologists and restorers as part of the cloning project.
Edited translation from Al-Masry Al-Youm
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Antiquities Minister inaugurates first Pharaonic cloning center in Luxor - Egypt Independent
Its been 20 years since scientists in Scotland told the world about Dolly the sheep, the first mammal successfully cloned from an adult body cell. What was special about Dolly is that her parents were actually a single cell originating from mammary tissue of an adult ewe. Dolly was an exact genetic copy of that sheep a clone.
Dolly captured peoples imaginations, but those of us in the field had seen her coming through previous research. Ive been working with mammalian embryos for over 40 years, with some work in my lab specifically focusing on various methods of cloning cattle and other livestock species. In fact, one of the coauthors of the paper announcing Dolly worked in our laboratory for three years prior to going to Scotland to help create the famous clone.
Dolly was an important milestone, inspiring scientists to continue improving cloning technology as well as to pursue new concepts in stem cell research. The endgame was never meant to be armies of genetically identical livestock: Rather, researchers continue to refine the techniques and combine them with other methods to turbocharge traditional animal breeding methods as well as gain insights into aging and disease.
Dolly was a perfectly normal sheep who became the mother of numerous normal lambs. She lived to six and a half years, when she was eventually put down after a contagious disease spread through her flock, infecting cloned and normally reproduced sheep alike. Her life wasnt unusual; its her origin that made her unique.
Before the decades of experiments that led to Dolly, it was thought that normal animals could be produced only by fertilization of an egg by a sperm. Thats how things naturally work. These germ cells are the only ones in the body that have their genetic material all jumbled up and in half the quantity of every other kind of cell. That way when these so-called haploid cells come together at fertilization, they produce one cell with the full complement of DNA. Joined together, the cell is termed diploid, for twice, or double. Two halves make a whole.
From that moment forward, nearly all cells in that body have the same genetic makeup. When the one-cell embryo duplicates its genetic material, both cells of the now two-cell embryo are genetically identical. When they in turn duplicate their genetic material, each cell at the four-cell stage is genetically identical. This pattern goes on so that each of the trillions of cells in an adult is genetically exactly the same whether its in a lung or a bone or the blood.
In contrast, Dolly was produced by whats called somatic cell nuclear transfer. In this process, researchers remove the genetic material from an egg and replace it with the nucleus of some other body cell. The resulting egg becomes a factory to produce an embryo that develops into an offspring. No sperm is in the picture; instead of half the genetic material coming from a sperm and half from an egg, it all comes from a single cell. Its diploid from the start.
Dolly was the culmination of hundreds of cloning experiments that, for example, showed diploid embryonic and fetal cells could be parents of offspring. But there was no way to easily know all the characteristics of the animal that would result from a cloned embryo or fetus. Researchers could freeze a few of the cells of a 16-cell embryo, while going on to produce clones from the other cells; if a desirable animal was produced, they could thaw the frozen cells and make more copies. But this was impractical because of low success rates.
Dolly demonstrated that adult somatic cells also could be used as parents. Thus, one could know the characteristics of the animal being cloned.
By my calculations, Dolly was the single success from 277 tries at somatic cell nuclear transfer. Sometimes the process of cloning by somatic cell nuclear transfer still produces abnormal embryos, most of which die. But the process has greatly improved so success rates now are more like 10 percent; its highly variable, though, depending on the cell type used and the species.
More than 10 different cell types have been used successfully as parents for cloning. These days most cloning is done using cells obtained by biopsying skin.
Genetics is only part of the story. Even while clones are genetically identical, their phenotypes the characteristics they express will be different. Its like naturally occurring identical twins: They share all their genes but theyre not really exactly alike, especially if reared in different settings.
Environment plays a huge role for some characteristics. Food availability can influence weight. Diseases can stunt growth. These kinds of lifestyle, nutrition or disease effects can influence which genes are turned on or off in an individual; these are called epigenetic effects. Even though all the genetic material may be the same in two identical clones, they might not be expressing all the same genes.
Consider the practice of cloning winning racehorses. Clones of winners sometimes also will be winners but most of the time theyre not. This is because winners are outliers; they need to have the right genetics, but also the right epigenetics and the right environment to reach that winning potential. For example, one can never exactly duplicate the uterine conditions a winning racehorse experienced when it was a developing fetus. Thus, cloning champions usually leads to disappointment. On the other hand, cloning a stallion that sires a high proportion of race-winning horses will result very reliably in a clone that similarly sires winners. This is a genetic rather than a phenotypic situation.
Even though the genetics are reliable, there are aspects of the cloning procedure that mean the epigenetics and environment are suboptimal. For example, sperm have elegant ways of activating the eggs they fertilize, which will die unless activated properly; with cloning, activation usually is accomplished by a strong electric shock. Many of the steps of cloning and subsequent embryonic development are done in test tubes in incubators. These conditions are not perfect substitutes for the female reproductive tract where fertilization and early embryonic development normally occur.
Sometimes abnormal fetuses develop to term, resulting in abnormalities at birth. The most striking abnormal phenotype of some clones is termed large offspring syndrome, in which calves or lambs are 30 or 40 percent larger than normal, resulting in difficult birth. The problems stem from an abnormal placenta. At birth, these clones are genetically normal, but are overly large, and tend to be hyperinsulinemic and hypoglycemic. (The conditions normalize over time once the offspring is no longer influenced by the abnormal placenta.)
Recent improvements in cloning procedures have greatly reduced these abnormalities, which also occur with natural reproduction, but at a much lower incidence.
Many thousands of cloned mammals have been produced in nearly two dozen species. Very few of these concern practical applications, such as cloning a famous Angus bull named Final Answer (who recently died at an old age) in order to produce more high-quality cattle via his clones sperm.
But the cloning research landscape is changing fast. The driving force for producing Dolly was not to produce genetically identical animals. Rather researchers want to combine cloning techniques with other methods in order to efficiently change animals genetically much quicker than traditional animal breeding methods that take decades to make changes in populations of species such as cattle.
One recent example is introducing the polled (no horns) gene into dairy cattle, thus eliminating the need for the painful process of dehorning. An even more striking application has been to produce a strain of pigs that is incapable of being infected by the very contagious and debilitating PRRS virus. Researchers have even made cattle that cannot develop Mad Cow Disease. For each of these procedures, somatic cell nuclear transplantation is an essential part of the process.
To date, the most valuable contribution of these somatic cell nuclear transplantation experiments has been the scientific information and insights gained. Theyve enhanced our understanding of normal and abnormal embryonic development, including aspects of aging, and more. This information is already helping reduce birth defects, improve methods of circumventing infertility, develop tools to fight certain cancers and even decrease some of the negative consequences of aging in livestock and even in people. Two decades since Dolly, important applications are still evolving.
This article was originally published on The Conversation. Read the original article.
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20 years after Dolly: Everything you always wanted to know about ... - Source
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A group of Harvard researchers have announced that they are close to resurrecting the woolly mammoth. The researchers believe they are less than two years away from creating a functioning embryo, although creating a fully-grown mammoth would take much longer.
Bringing back an extinct animal is not easy. The mammoth is an ideal candidate to become the first resurrected species, both because of the large amount of intact mammoth specimens available, and also because its close living relatives, the elephants, still walk the Earth. Still, there is considerable debate around just how to bring the mammoth back to life.
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The primary issue is the lack of suitable genetic material for cloning. While a significant amount of mammoth tissue has been found, most of the DNA has been destroyed after being frozen for so long. A team of South Korean researchers are hoping to find enough DNA to clone a mammoth, but the Harvard group is taking a different approach.
The Harvard team is genetically modifying an elephant genome, replacing some elephant genes with mammoth ones. Essentially, they're trying to manually rebuild the mammoth genome. The final product won't be exactly the same as the extinct version, but it'll look pretty much identical.
The Harvard researchers ultimately want to implant their engineered genome inside an elephant embryo, which they expect will happen sometime in the next two years. Once that occurs, they will try to bring the embryo to term using an artificial womb. However, such a feat may not be possible for several more years, so it might be a while before you can see a live woolly mammothor a theme park full of them.
Source: The Guardian
Read more here:
Scientists Are Close to Cloning a Woolly Mammoth - Popular Mechanics
By Christopher Thomas Scott and Irving L. Weissman, MD
Most cloningthe process of making an exact genetic replica of a cell, a tissue, or an organismhappens naturally. When the fertilized egg first divides, occasionally each daughter cell goes on to form separate embryos. The result: identical twins, each one a clone of the other. Organisms that reproduce asexually, such as aphids, brine shrimp, yeast, and bacteria, are clones. Horticulture uses the term clone for a form of propagation that involves cutting up one plant into pieces that are used to grow hundreds or thousands of identical seedlings.
Scientific cloning takes up where nature leaves off. Genetic, or molecular, cloning makes copies of genes or segments of DNA. They can be used to create colonies of genetically modified bacteria or viruses, which can produce drugs and vaccines. Laboratory culture methods can clone a single cell into a population of cells, comprising a limitless number of identical progeny. Various techniques to make copies of whole animals are called reproductive cloning. Finally, there is reprogramming, in which the genes from adult cells are reset to an embryonic state. The hope is that these cells can help scientists understand genetic disease mechanisms and create stem cell-based therapies for diseases and injuries that are genetically matched to individual patients. As of this writing, no such therapies exist.
Cloning technologies are essential tools; without them modern biology would still be the stuff of science fiction. Cloning has led to scores of important drugs and newly developed therapies, such as human insulin, interferon to fight viral infections, and blood growth factors such as erythropoietin to generate new red blood cells.
The ethical debates surrounding cloning pivot on several issues. One controversial method of cloningsomatic cell nuclear transfer (SCNT)involves the production of a two-to-four day-old blastocyst (a preimplantation embryo), whose cells are then removed to make a line of embryonic stem cellsa process that destroys the embryo. Another concern is over what might be done with these embryos prior to deriving a stem cell line. Because the technique employs some of the same culture methods used by in vitro fertilization clinics, some fear a cloned human embryo could be transferred to a woman, possibly resulting in a baby. And experience with animal reproductive cloning suggests more ethically troubling issuesearly implantation of these clones always results in their death and often causes maternal death or morbidity. With cloning that involves human embryos, still another concern is assuring that the process for obtaining human eggs for research involves proper informed consent from the donors.
How does the embryo control development by gene expression, the process by which genes turn on and off? Could a developmentally older or differentiated cell have its genes reset to an earlier version of itself by being put into an embryo?
Researchers first addressed these questions in the 1950s (see box, Cloning and Stem Cell Milestones: A Timeline). A nucleus from an unfertilized frog egg cell was removed by sucking it out with a very fine, hollow needle called a micropipette. In the same fashion, a nucleus was removed from a cell inside a developing frog embryo. Injecting it into the empty egg began the process of embryogenesis. This process rarely resulted in tadpoles, a few of which grew into frogs. This was the earliest version of nuclear transfer, the cloning technique in which a nucleus without a cell is inserted into a cell without a nucleus. The evidence of the eggs power to reprogram genes was an important result, and the research moved to mammals.
Until the appearance of Dolly, a cloned sheep, most animal clones resulted from nuclei taken directly from embryos. Ian Wilmut, a Scottish researcher, inserted a somatic cell taken from the udder of a six-year-old sheep into an unfertilized sheep egg whose chromosomes had been removed. After the procedure, the proteins in the eggs cytoplasm reprogrammed the developmental instructions contained in the DNA. The genes switched from their fully differentiated mammary cell program to a program that produced a baby sheep. This is an enormously inefficient method for producing offspring, presumably because there is not enough time for the eggs cytoplasm to correctly reprogram all the genes from the udder cell to a pluripotent state. Over 99% of such clones die after implantation. Also, animals made in this fashion are not true genetic clones. The egg contains genetic material outside the chromosomes in organelles called mitochondria. The resulting organism or cell line is a clone at the chromosomal level, but has a mixture of mitochondrial genes.
The same method used to produce an animal cloneSCNTcould theoretically be used to make a cloned line of human cells with a near genetic match to any person who needed them. The nucleus from a donor cell would be inserted into an egg stripped of its nucleus. Then, just as in animal cloning, the egg would divide, and an embryo might be cultured to the blastocyst stage and have its stem cell line harvested.
Another hope is that reprogrammed cell lines made by SCNT could be powerful tools for studying the genetic basis of human development and disease, as well as for drug discovery. In the most optimistic scenario, cloning could produce a lifetime supply of therapeutic stem cells genetically matched to a patient and, therefore, posing minimal risk of immune rejection. Unfortunately, the mitochondrial mismatches usually lead to immune rejection, albeit at a slower rate than when the chromosomal genes are also unmatched. As in other dimensions of stem cell research, the promise of therapeutic stem cells has proven difficult to realize due to moral and technical obstacles.
These difficulties came into sharp focus with the South Korean stem cell scandal. A research team announced in 2004 and 2005 that, using somatic cell nuclear transfer, they had established the first patient-specific human embryonic stem cell lines. Moreover, the researchers claimed to have accomplished the cloning with astounding efficiencies, easing worries that hundreds or thousands of human eggs would be needed. It was later revealed that thousands of eggs were indeed used, and some were obtained under questionable circumstances from women working in the laboratories. The lines themselves were not made by SCNT; they were derived from parthenoteseggs treated in a way that causes them to divide without being fertilizedor possibly directly from IVF embryos.
This fraud fueled efforts to find uncontroversial substitutes for cloned human cells. First, experiments in which somatic and embryonic stem cells were fused successfully reprogrammed the genes in the somatic cell nucleus. This meant that genes expressed in embryonic cells keep them pluripotent, or able to make any cell or tissue in the body. More recently, researchers have reprogrammed skin cells with subsets of these embryonic genes by introducing them with mouse leukemia virus vectors. These experiments make cell lines with embryonic qualities (see chapter 34, Stem Cells ). These linescalled induced pluripotent stem cells (iPS)express markers and genes indicative of embryonic stem cells; they also possess the ability to redifferentiate into adult cell types. If they are found to be equivalent to embryonic cells, then they couldin principlereplace nuclear transfer as a means of generating pluripotent lines that genetically match a patient. Since both the chromosomes and the mitochondria come from the induced cell, iPS cells are a better match than stem cells from SCNT. Though several labs have now made human iPS lines, experiments with mouse iPS cells show that the genes and the vectors that carry them cause cancer. Elimination of these oncogenes is a goal of many reprogramming labs.
Blastocyst In humans, a two-to-four-day-old embryo, roughly the diameter of a human hair.
Embryo An early stage of human development. Medical texts describe embryonic development as a gradual process, beginning when the blastocyst attaches to the uterus and ending eight weeks later, as the organs begin to form.
Differentiation The process by which stem cells make other kinds of cells and tissue in the body.
Stem cell A cell that has the capacity to make new copies of itself and differentiate.
Somatic cell A differentiated cell of the body, such as a skin or intestinal cell.
Induced pluripotent stem (iPS) cells Stem cells derived from somatic cells following transfer of reprogramming genes taken from embryonic stem cells. The cells exhibit pluripotence, or the ability to copy themselves and change into different types of cells.
Reprogramming The molecular and chemical mechanisms at work in SCNT and iPS cell experiments that reset genes in differentiated cells (such as skin cells) to an embryonic state.
Somatic cell nuclear transfer (SCNT) Also called nuclear transfer. A technical step in which a somatic cell nucleus (containing the genetic material) is removed and transferred to an egg with no nucleus.
Therapeutic cloning A popular term for the anticipated application of SCNT to make genetically-matched embryonic stem cell lines for therapies.
Nuclear transfer is a crude disruption of a delicate and barely understood biological process. Most cloned animals die during gestation and, because of abnormal placentas or abnormally large fetuses, can kill the surrogate mother. Of the few reproductive clones that survive, many are unhealthy, most likely due to failures of reprogramming. Skeletal abnormalities and arthritis are common, as are malformed organs, circulatory disorders, respiratory problems, and immune system dysfunction. Cloned animals often suffer from either abnormally high or low birth weight. For these reasons alone, attempting to clone a human being would be clearly unethical. As a result, every major national and international ethical and scientific body condemns human cloning.
However, even if cloning humans could be done as safely as IVF, opinions on whether it should be allowed are divided. Would we deny an infertile couple a chance to have a cloned child? Are there other personal and private reasons for humans to clone a lost loved one, and should we deny them that possibility? Critics maintain that research cloning may lead to a slippery slopecondoning the process for research purposes could eventually result in condoning it for reproductive purposes. Cloning babies also creates life without sexual reproduction, which some believe undermines a vital dimension of humanness.
These arguments are based on an imagined world without societal checks or balances invoked by a moral consensus against the practice of cloning humansthe same pressures that condemn unethical treatment of human subjects in clinical research or payment for organs used in transplant procedures. Once it was clear that a stem cell line could make all tissues, we would certainly have a moral responsibility to use the line of cells to understand disease. These cells could also eventually provide therapies and cures. The moral justifications rest on the positive principle of beneficence: the research may reduce human suffering due to aging, injury, and disease, especially for those who may have a very short window of opportunity for treatment.
Resource constraints join funding restrictions as major hurdles to producing human stem cell lines by somatic cell nuclear reprogramming. Current technology requires the use of thousands of surplus or donated human eggs. The egg retrieval procedure is invasive and not without risk to women, raising concerns about obtaining proper informed consent. Whether women should be paid for removal of their eggs is hotly debated among ethics and policy scholars; national and state guidelines prohibit paying women for eggs over and above reasonable expenses related to the clinical procedure. Others point out inconsistencies in social policy that permit women to sell their eggs for reproductive purposes. Nevertheless, research using human and primate eggs may dramatically improve the efficiency of reprogramming, and, unlike the creation of iPS cells, nuclear transfer does not involve introduction of cancer genes.
The United States is the only nation conducting human embryonic stem cell research that does not have a federal law prohibiting human reproductive cloning. This incongruous fact springs from legislative wrangling in Congress since 2001. Opponents of human embryonic stem cell research introduced measures that would criminalize both human reproductive cloning and production of such lines by nuclear transfer. The tightly bound issues prevented a majority rule against reproductive cloning that would have carried easily in other countries. The vacuum in federal policy has led to a welter of state laws, some of which are permissive and others restrictive. It also leads to border dilemmas (by restricting the movement of eggs and cloned lines from permissive to restrictive states and vice versa) and, in South Dakota and Michigan, the threat of jail and other penalties for researchers. The regulatory environment is uncertain in the majority of states that are either silent on cloning or have laws that consider donated IVF embryos separately from embryos made for research purposes, including embryos made by nuclear transfer.
What is lost in the discussion about human embryonic stem cell funding restrictions is a longstanding federal prohibition on funding of embryo research generally, a legislative action that swept essential questions about infertility, reproductive medicine, and prenatal diagnosis beyond the reach of many American clinicians and scientists. Just as political controversies surrounding abortion and assisted reproductive technologies are used as proxies for restrictions on embryonic stem cell research, lines made by nuclear transfer are presumably bound by the same prohibitions as frozen embryos, despite national ethics committees and advisory groups such as the National Academy of Sciences recommending that the research proceed.
The future of cloning research faces at least four major scientific and policy questions.
Christopher Thomas Scott is a senior research scholar at the Center for Biomedical Ethics at Stanford University and Irving L. Weissman, MD, is a professor at Stanford University.
Christopher Thomas Scott and Irving L. Weissman, Cloning, in From Birth to Death and Bench to Clinic: The Hastings Center Bioethics Briefing Book for Journalists, Policymakers, and Campaigns, ed. Mary Crowley (Garrison, NY: The Hastings Center, 2008), 25-30.
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