Daily Archives: June 3, 2017

Ancient Egyptians were an archaeologist's dream. Theyleft behind intricate coffins, massive pyramids and gorgeous hieroglyphs, the pictorial writing code cracked in 1799. Egyptians recorded tales of royalty and gods. They jotted downlife's miscellanies, too, as humdrum as beer recipes anddoctor's notes.

But there was one persistent hole in ancient Egyptian identity: their chromosomes. Cool, dry permafrost can preserve prehistoric DNA like anatural freezer, but Egypt is a gene incinerator. The regionis hot. Within the mummies' tombs, where scientists would hope to findgenetic samples, humidity wrecked their DNA. What's more, soda ash and other chemicals used by Egyptian embalmers damaged geneticmaterial.

A study led by researchers at the Max Planck Institute for the Science of Human History and the University of Tubingen in Germany managed to plug some of those genetic gaps. Researchers wrunggenetic material from 151 Egyptian mummies, radiocarbon dated between Egypt'sNew Kingdom (the oldest at 1388 B.C.) to the Roman Period (the youngest at 426 A.D.), as reported Tuesday in the journalNature Communications.

Johannes Krause, a University of Tubingen paleogeneticist and an author of the study, said the major findingwas that for 1,300 years, we see complete geneticcontinuity. Despite repeated conquests of Egypt, by Alexander the Great, Greeks, Romans, Arabs and Assyrians the list goes onancient Egyptians showed little genetic change.The other big surprise, Krause said, was we didn't find much sub-Saharan African ancestry.

The remains came from Abusir el-Meleq, an ancient Nile community in the middle of Egypt. From the mummies the scientists extracted bone, teeth and soft tissue samples. (Although Egyptian embalmers removed thebrains of the deceased, the scientists wrote that in most cases, non-macerated mummy heads still have much of their soft tissue preserved.)

The hard samples yielded the most DNA, perhaps because the teeth and bones were protected by soft tissue or because the embalming processes left tougher material intact.After preparing the samples in a sterilized room in Germany, the researchers bathed the samples in UV radiation for an hour to minimize contamination.

Ancient Egyptianswere closely related to people who lived along the eastern Mediterranean, the analysis showed. They also shared genetic material with residents of the Turkish peninsula at the time and Europe.

Given Egypt's location at the intersection of Africa, Europe and Asia, and the influx of foreign rulers, Krause said he was surprised at how stable the genetics seemed to be over this period. The scientists were particularly interested in the change in ruling class at the turn of the first millennium. First came the Hellenistic dynasty, in the aftermath of Alexander the Greats conquests, from 332 B.C. to 30 B.C., and thenRoman rule from 30 B.C. to about 400 A.D. And yet the genetics of the Abusir el-Meleq community appeared to be unperturbed by shifting politics.

The scientists compared these ancient genetics with those of 100 modern Egyptians and 125 modern Ethiopians that had been previously analyzed. If you ask Egyptians, they'll say that they have become more European recently, Krause said. We see exactly the opposite, he said.

It was not until relatively recently inEgypt's long history that sub-Saharan geneticinfluences became more pronounced.In the last 1,500 years, Egypt became more African, if you want, Krause said.

In their paper, the researchers acknowledged that all our genetic data were obtained from a single site in Middle Egypt and may not be representative for all of ancient Egypt. In the south of Egypt, the authors wrote, sub-Saharan influences may have been stronger.

This study left two gaps in the Egyptian timeline that Krause wants to fill, he said. It is not clear when theAfrican gene flow, present in modern Egyptians, occurred. Nor could the study determine theorigin of the Egyptians.The other big question is, 'Where did the ancient Egyptians come from?' Krause said. To answer that, scientists will have to find genomes back further in time, in prehistory.

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Egyptian mummy DNA shows Mediterranean, Turkish and European ...

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Dutch families win right to test DNA of sperm bank doctor BBC News A Dutch court has approved a request by families seeking DNA tests on the belongings of a late fertility clinic doctor accused of using his own sperm in dozens of cases. Jan Karbaat is suspected of fathering about 60 children at the centre he ran in ... DNA tests allowed in IVF doctor scandal, Dutch court rulesDeutsche Welle Dutch court allows posthumous DNA tests on doctor in IVF scandalThe Guardian Court allows DNA tests on fertility doctor accused of sperm swapNew York Daily News The Hindu -UPI.com -Sky News all 11 news articles »

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Dutch families win right to test DNA of sperm bank doctor - BBC News

A Chesterfield County teen who was identified through the states DNA databank as a suspect in the 2015 rape and beating of a 47-year-old Chesterfield woman was convicted Friday of maliciously wounding her in a random attack.

In a deal struck by the prosecution and defense after the teens first trial on rape and sodomy charges ended with a hung jury, Quaseer L. Carter, 18, pleaded no contest to the felony count in the Oct. 7, 2015, attack. The woman was raped, sodomized and struck twice in the face after she was dragged off the street into a grassy area between two homes, according to evidence at Carters first trial in late March.

The plea agreement was reached after both sides recognized they faced substantial credibility issues with their respective cases. The victim, who attended Fridays proceeding in Chesterfield Circuit Court, was on board with the decision, Chesterfield prosecutor Stephen Sharpe told the court.

On the day of the attack, the victim was helping her former husband pack up some items for an upcoming trip at his home in the 2900 block of Goolsby Court, Sharpe said in a summary of evidence. At one point, she left and walked down Goolsby Avenue to a friends house less than a quarter-mile away to socialize.

She drank some beer with her friend before eventually leaving to walk back to her former husbands home at about 9 p.m. She was only a few houses away when a black male stopped her and asked for a cigarette, Sharpe said in his summary.

As the victim looked for a cigarette, the suspect struck her in the face in a blow that knocked her to the ground. The man then sexually assaulted the woman before raising her to her knees, when he struck her again in the face. She again was knocked to the ground.

The victim testified at Carters first trial that something must have startled the suspect, because he jumped up quickly and ran off.

The victim managed to stumble back to her former husbands house, where police were immediately called. The woman suffered several scratches and cuts, a bloodied face and other injuries to her body, Sharpe said.

The suspect was wearing dark pants and a dark-hooded sweatshirt with the hood pulled down tightly over his face. It was dark outside, and the victim was unable to make out his facial features, according to evidence.

After the victim reported the attack to police, she was taken to a local hospital, where a physical evidence recovery kit was used to collect semen and other biological evidence.

The recovered evidence was sent to the Virginia Department of Forensic Science, where a sample was entered into the departments computerized DNA databank that contains the DNA profiles of hundreds of thousands of convicted felons. A match was made that identified Carter as a suspect.

Carters genetic fingerprint had been added to the database after his conviction as a juvenile in Richmond on a charge of felony theft from a person. Under Virginia law, juvenile offenders ages 14 or older and convicted of a felony are required to submit a DNA sample, the same as adult offenders.

Two weeks after the Oct. 7, 2015, attack on the woman, Carter was arrested in a carjacking that occurred just two days after the Goolsby Avenue assault. But a Chesterfield jury acquitted him of that charge at his April 21 trial.

At his rape trial, Carter claimed in testimony that his victim had propositioned him for sex in exchange for money an accusation that prosecutors said the woman would emphatically deny. The teen offered no explanation for the injuries she sustained during the attack. But he claimed she filed charges against him as an act of revenge, because she was angry that he only had $5 to pay her for sex.

Carter, who was 16 at the time and lived in the area, testified that he was walking home to dinner when he encountered the woman.

The teen faces up to five years in prison when he is sentenced in September. The judge allowed him to remain free on bond, but he remains under electronic monitoring with an ankle bracelet.

Originally posted here:
Chesterfield teen ID'd as rape suspect through DNA "cold hit" pleads no contest in 2015 attack - Richmond.com

June 2, 2017 by Hayley Dunning Proteins interacting with the DNA strand. Credit: Imperial College London

Scientists have watched a cell's genetic machinery in the first stages of 'reading' genes, giving a potential way to stop the process in bacteria.

By reading certain genes - a process known as transcription - cells can produce and regulate proteins, which perform almost all the functions necessary for life.

In the new study, researchers used an extremely powerful technique called cryo-electron microscopy to physically see how this process happens in detail, for the first time. The insights could help researchers target this stage of transcription in bacteria with new antibiotics.

DNA is composed of two strands, which are normally linked together in a twisted helical structure. The strands are pulled apart by several specialist molecules that 'melt' it preventing the strands from coming back together as they normally try to do. This step in transcription usually happens very quickly, with a lot of changes occurring over a short time span, meaning it has been impossible to track in detail before.

In the study published today in Molecular Cell, the research team led by scientists at Imperial College London viewed the DNA opening in action.

Since transcription of DNA is so fundamental to the functioning of a cell, the team believe that knowing how it operates in bacteria could provide avenues for blocking the process, potentially shutting down the actions of harmful infections.

New ways to stop bacteria

Lead researcher Professor Xiaodong Zhang, from the Department of medicine at Imperial, said: "Bacteria are becoming increasingly resistant to antibiotics, so our insights into the first stage of transcription provide new ways of thinking about stopping bacteria.

"Understanding how the fundamental machinery works hopefully gives us additional tools for developing new kinds of antibiotics. As we investigate more steps in the process of transcription, we may find more stages during which we can intervene and attack harmful bacteria."

The process of transcription occurs in all living things and plays a crucial role in many cellular processes, including those related to diseases like cancer. The new insights might therefore apply across a whole range of organisms and disease processes.

Activating transcription

In particular, the team studied the action of a protein called sigma54, which controls a wide range of bacterial defences, holding them back until they need to be used. If drugs could be designed to interfere with this step, and preserve sigma54's power to hold back defences, they could make bacteria more vulnerable to attack.

Sigma54 unleashes the bacterial defences after being activated by a protein that changes sigma54's shape. The 'activator' protein, together with sigma54, then forms a protein wedge that drives the two DNA strands apart. The bacterial defence genes are then read and kicked into action.

The researchers were able to watch this transcription process in detail, giving them new insights into how they might use sigma54 to disable the bacteria's defences.

Study co-author Professor Martin Buck, from the Department of Life Sciences at Imperial, said: "DNA contains genetic information, which is converted to proteins that carry out all cell functions. Transcription is the first stage in accessing that information.

"It underpins all environmental adaptation in organisms it's how cells deal with their changing environments or even become abnormal, such as in cancer cells. Our work could therefore have implications across a range of biological processes."

Explore further: Discovery of trigger for bugs' defenses could lead to new antibiotics

More information: Robert Glyde et al. Structures of RNA Polymerase Closed and Intermediate Complexes Reveal Mechanisms of DNA Opening and Transcription Initiation, Molecular Cell (2017). DOI: 10.1016/j.molcel.2017.05.010

It is unusual enough to see one of nature's biggest, rarestnot to mention smelliestflowers bloom. But it is extraordinary to see two bloom at once.

As the United Nations Oceans Conference convenes in New York, a new paper calls on marine scientists to focus on social issues such as human rights violations in the seafood industry.

Scientists are now confident animal life on solid ground started with a few short bursts of marine creatures making the leap from the oceans.

Scientists have watched a cell's genetic machinery in the first stages of 'reading' genes, giving a potential way to stop the process in bacteria.

Passing skills down through the generations, previously thought to be unique to humanity, has been discovered in chimpanzees.

Once we start coloring our hair, we may be surprised to learn that we begin to have a problem in common with plant biologists: finding the right dye for our roots. In the case of the biologists, just the right chemical is ...

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Fact: The production and reproduction of life depends on the most complex, dense and miniaturized codes and coded information known to man.

Fact: the whole scientific community cannot understand the huge ammounts of DNA coded information.

Fact: codes and coded information are imaterial meanings ascribed to sequences of symbols (vg. A, T, G, C) and not matter or energy.

Fact: There is no natural law or physical process able to create meaningful codes and coded information.

Fact: There is no viable naturalistic explanation for the origin of life.

Fact: the molecular machines that transcribe, read and execute DNA coded information are thenselves coded in DNA.

Fact: random mutations are cumulative and degerative creating "noise", degrading information and causing disease, cancer, suffering and death.

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First-ever look at DNA opening reveals initial stage of reading the ... - Phys.Org