DNA Study Reveals First Native Americans May Have Come from Siberia
An individual who lived in Siberia about 24,000 years ago has a genetic signature that is closer to modern Native American than current-day Siberians, a study has found.
This latest finding by researchers at the University of Copenhagen helps in understanding the ancestral Native Americans and also the genetic landscape of Eurasia nearly 24,000 years ago.
Earlier in 2009, researchers analyzed the sample of a juvenile individual (MA-1) from the Upper Palaeolithic site of Mal'ta in south-central, Siberia. The genomic study of the juvenile uncovers the origin of ancestors of the modern day Native Americans.
The researchers noticed that the individual MA-1 had no genetic resemblance with the modern population of South Siberia, which is the place of its origin. Rather, they noticed that both the nuclear genomes and mitochondrial genomes of the juvenile had a lot of similarity with the western Eurasians. This new finding shows that in the ancient western Eurasians were spread across a much wider territory than they are today.
The most interesting and important find of this study is the relation between the juvenile MA-1 and modern Native Americans. The ancestor of the western Eurasians is closely related to the modern Native Americans and not to the East Asians.
It was noticed that the genetic affinity between MA-1 and Native Americans was intervened by a gene flow event from the MA-1 into the First Americans. The researchers said that two separate old world populations formed the First American gene pool; one of which was related to the modern day East Asians and the other to the Siberian Upper Palaeolithic population, according to the new release
"The result came as a complete surprise to us. Who would have thought that present-day Native Americans, who we learned in school derive from East Asians, share recent evolutionary history with contemporary western Eurasians? Even more intriguingly, this happened by gene flow from an ancient population that is so far represented only by the MA-1 individual living some 24,000 years ago," says Professor Eske Willerslev from the Centre for GeoGenetics who led the study.
Apart from MA-1 the researchers also looked at a second south-central Siberian that is 17,000 years old and was unearthed from the Afontova Gora-2site. They noticed that the genomic signature of the individual matched to that of MA-1. It was seen that the individual has a close association with modern western Eurasians and Native Americans but not to East Asians.
Professor Kelly Graf from the Center for the Study of the First Americans concluded saying, "Our findings are significant at two levels. First, it shows that Upper Paleolithic Siberians came from a cosmopolitan population of early modern humans that spread out of Africa to Europe and Central and South Asia. Second, Paleoindian skeletons with phenotypic traits atypical of modern-day Native Americans can be explained as having a direct historical connection to Upper Paleolithic Siberia."
The findings were documented in the journal Nature.