Tracing Human Movements from Siberia to the Americas: Insights from Genetic Studies

Abstract

Based on archeological and genetic data, the Altai-Sayan region appears to be the area from which human populations began expanding eastward toward Beringia some 25,000 years ago, and then much later to the west with the expansion of Turkic- and Mongolic-speaking groups. The initial human expansion into the New World appears to have occurred around 15,000–20,000 BP, with most genetic data supporting a single early expansion into the Americas giving rise to Amerindian populations. The ancestors of Eskimo-Aleut- and Na-Dene-speaking groups entered northern North America around 8,000–10,000 years ago, having become genetically distinctive from Amerindian populations to the south. From a Eurasian perspective, mtDNA and Y-chromosome data indicate that southern Altaians and Native Americans shared a common genetic ancestor some 20,000–25,000 BP. Such data from indigenous Altaians also link them to Japanese and Koreans (possibly Tibetans), tentatively supporting connections among Altaic (Transeurasian) speakers. Within the Altai-Sayan region, northern Altaians show genetic affinities with Yeniseian, Ugric, and Samoyedic speakers to the north, whereas southern Altaians have greater affinities to other Turkic-speaking populations of southern Siberia and Central Asia, revealing complex population dynamics there. Turkic and Mongolic groups show genetic influences from both West and East Eurasia, reflecting the entry of steppe peoples into Central Asia several thousand years ago, while Mongols have strongly genetically influenced southern Altaians and Altaian Kazakhs (Y-chromosome haplogroups C3c and O3e). Overall, this research has yielded important insights into the phylogeography and ancestry of populations from across Eurasia and the Americas.