A group of ancient humans called Denisovans - who were closely related to Neanderthals - may have contributed somewhat to the modern human genome, say scientists who sequenced the Denisovan genome.
The existence of the Denisovans only came to light in 2010 when a piece of a finger bone and two molars were discovered in the Denisova Cave in southern Siberia.
How the study was done
In a new study, published online in ScienceExpress, Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues report on their analysis of DNA from the finger bone.
By comparing the genomes of several modern humans from around the world to the newly sequenced Denisovan genome, the investigators found that the ancient humans shared some genes with modern humans, but the extent varies depending on the location of the modern humans.
For example, the Denisovans share more genes with people from Papua New Guinea than with any other population of modern humans. The researchers also found that Denisovans share more genes with people in Asia and South America than with those in Europe. However, this likely reflects interbreeding between modern humans and the Denisovans' close relatives the Neanderthals, rather than gene flow from the Denisovans themselves, the researchers explained in a news release from the American Association for the Advancement of Science.
It was also found that the Denisovan whose genome was sequenced carried genes that are associated with dark skin, brown hair and brown eyes in modern humans, the study authors pointed out in the news release.
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The Natural History Museum in London has more about the Denisovans.
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