Geneticist Connie Mulligan of the University of Florida called the findings 'jaw-dropping'. DNA from this ancient Siberian skeleton offers clues to the first Americans. Picture: The State Hermitage museum, St. Petersburg
New DNA findings, if confirmed, have stunning implications for our understanding of both pre-historic Siberians - and native Americans. They would suggest that, contrary to previous understanding, some indigenous populations are - in fact - European or West Asiatic in origin.
The Danish-US research was carried out on the bones of a Siberian boy whose remains were found near the village of Mal'ta close to Lake Baikal in the 1920s in a grave adorned with flint tools, pendants, a bead necklace and a sprinkling of ochre. The remains are held in the world famous Hermitage Museum in St Petersburg and analysis of a bone in one of his arms represents 'the oldest complete genome of a modern human sequenced to date', according to Science magazine.
'His DNA shows close ties to those of today's Native Americans. Yet he apparently descended not from East Asians, but from people who had lived in Europe or western Asia,' said ancient DNA expert Eske Willerslev of the University of Copenhagen. 'The finding suggests that about a third of the ancestry of today's Native Americans can be traced to 'western Eurasia'.'
The research may help explain why 'European ancestry previously detected in modern Native Americans do not come solely from mixing with European colonists, as most scientists had assumed, but have much deeper roots', said the report.
It may also raise a similar question about the 'European look' of some ancient Siberians - for example in the tattooed permafrost princess Ukok found in a burial chamber in the Altai Mountains, whose remains date from around 2,500 years ago.
'Princess' Ukok's shoulder, tattoo of fantastic animal, and a drawing of it made by Siberian scientists. Picture and drawing: Elena Shumakova, Institute of Archeology and Ethnography, Siberian Branch of Russian Academy of Science
Russian scientists reconstructed her to show what many were surprised to be a European face, unrelated to the modern day Altai tribes. The finding is confirmed by DNA analysis which showed her to be Pazyryk in origin. Her group was part of the Samoyedic family, with elements of the Iranian-Caucasian substratum'.
The four year old boy was found near the Belaya River close to the village of Mal'ta which is famed for the discovery of ancient art, some of it showing close links to European discoveries of the same period. Willerslev and co-author Kelly Graf of Texas A&M University 'used a variety of statistical methods to compare the genome with that of living populations.
'They found that a portion of the boy's genome is shared only by today's Native Americans and no other groups, showing a close relationship.
'Yet the child's Y chromosome belongs to a genetic group called Y haplogroup R, and its mitochondrial DNA to a haplogroup U. Today, those haplogroups are found almost exclusively in people living in Europe and regions of Asia west of the Altai Mountains, which are near the borders of Russia, China, and Mongolia.'
Until now it has been widely believed that Native Americans were linked to Eastern Siberian tribes, having crossed Beringia, a vast Ice Age land bridge.
The magazine report stated: 'One expected relationship was missing from the picture - the boy's genome showed no connection to modern East Asians.
'DNA studies of living people strongly suggest that East Asians - perhaps Siberians, Chinese, or Japanese - make up the major part of Native American ancestors. So how could the boy be related to living Native Americans, but not to East Asians?'
The Mal'ta boy was related to people who later migrated across Beringia to the Americas. Picture: G.Grullon/Science
Willerslev and his team propose that earlier than 24,000 years ago 'the ancestors of Native Americans and the ancestors of today's East Asians split into distinct groups.
'The Mal'ta child represents a population of Native American ancestors who moved into Siberia, probably from Europe or west Asia. Then, sometime after the Mal'ta boy died, this population mixed with East Asians. The new, admixed population eventually made its way to the Americas.'
The timing is uncertain but 'the deep roots in Europe or west Asia could help explain features of some Paleoamerican skeletons and of Native American DNA today'. Some of the traces of Eurasian genetic signatures in modern Native Americans do not come from colonial times when incoming Europeans mixed with the indigenous population.
'Some of them are ancient,' said Willerslev. Geneticist Connie Mulligan of the University of Florida called the findings 'jaw-dropping'.
Yet perhaps the findings - the full details of which are due to be published soon in Nature journal - are not so surprising. Famed Russian archeologist Mikhail Gerasimov found art work at Mal'ta which show a close resemblance to European female figurines of the Upper Paleolithic period. The similarities extend to tools and dwelling structures.
Written by pipspiper
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