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See the face of your 100,000-year-old ancestor – HEALTH & SCIENCE



  Portrait of a female teenager Denisovan

Portrait of a female teenager Denisovan.
(photo credit: GOOD HAREL)

Meet "Denise," the first reconstructed anatomical profile of what has hitherto been considered mysterious Denisovans, a group of archaic people.

He was announced Thursday by the Hebrew University of Jerusalem. Researchers who have managed to recreate his profile say that their long-term research demonstrates the possible strategies available for forensic applications.

The Denisovans lived in Siberia and East Asia and were completed about 50,000 years ago, said Hebrew University of Jerusalem researcher Prof. Liran Carmel, who led the study. But exactly what Denisovan might look like is anyone's guess. That's because since their discovery in 2008, researchers have only three fossils to work with: a bone from the end of "Denise's" pinkie finger, a few teeth and a recently found lower bone of the jaw.

HU researchers were able to reconstruct Denisovan's profile over a three-year period by examining methylation patterns in their ancient DNA.

 3-D print reconstruction of a female Denisovan (Credit: Maayan Harel) "width =" 600 "height =" 420

Wikipedia explains that DNA methylation is a process by which methyl groups are added to the DNA molecule, thereby altering the activity of a DNA segment.

"Methylation provides a lot of information about gene transcription," Carmel explains.

By studying DNA methylation maps and comparing them with Neanderthals, another group of archaic humans disappeared in Europe some 40,000 years ago, as well as ancient Homo sapiens , the team understands what those differences might mean in Denisovan's anatomical features, based on what is known about human disorders in which these genes have lost function.

"We get a prediction about what parts of the skeleton are affected by the regulation of each gene's regulation and in what direction the skeletal part will change – for example, a longer or shorter femur bone, "says Dr. David Gokhman, now a postdoc at Stanford, also worked on the project. [19659004] Carmel says it is very difficult to obtain an anatomical profile from a DNA sequence, with most scientists and forensics teams able to state key details, such as whether the person whose DNA is included in h as dark hair or skin. However, DNA methylation has allowed researchers to make more detailed anatomic predictions.

 Dr. David Gokhman and Prof. Liran Carmel (Credit: Hebrew University of Jerusalem) "width =" 600 "height =" 420

The team has proven about 85% accuracy of their model by using the same technique to create anatomical models of Neanderthals and Chimpanzees, with known anatomical profiles.

"One of the most exciting moments occurred a few weeks after our paper was submitted for peer review," Carmel said. "Scientists discovered a jaw in Denisovan. We quickly compared this poem to our predictions and found that it matched perfectly.

" Without even planning for it, we received independent confirmation of our ability to rebuild whole anatomical profiles using DNA that we got from a single finger, "he continued.

Researchers have found that Denisovans attract similar patterns of human methylation. They also find that there are 56 anatomical features of which the Denisovans differed from modern humans and / or Neanderthals, 34 of them on the skull.

Previous research done outside the Hebrew University showed that up to 6% of those Melanesians and contemporary Aboriginal Australians contain Denisovan DNA. Further, Denisovan DNA may have contributed to the modern ability of the Tibetans survive at high altitudes and the Inuits' ability to withstand freezing temperatures.

Although Carmel states, "The use of our method directly for forensic application is currently not possible," because it is designed to study variations outside of modern human diversity and police need to find features within the range, "DNA methylation can provide a lot of information that will help the police."

He stated that in addition to obtaining DNA sequences, transcription could improve forensic data.

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