In the heartland of Eurasia: the multilocus genetic landscape of Central Asian populations

Abstract

In the heartland of Eurasia: the multilocus genetic landscape of Central Asian populations Begoña Martı́nez-Cruz1,7,10, Renaud Vitalis1,8,10, Laure Ségurel1,9, Frédéric Austerlitz2, Myriam Georges1, Sylvain Théry1, Lluis Quintana-Murci3, Tatyana Hegay4, Almaz Aldashev5, Firuza Nasyrova6 and Evelyne Heyer*,1 Located in the Eurasian heartland, Central Asia has played a major role in both the early spread of modern humans out of Africa and the more recent settlements of differentiated populations across Eurasia. A detailed knowledge of the peopling in this vast region would therefore greatly improve our understanding of range expansions, colonizations and recurrent migrations, including the impact of the historical expansion of eastern nomadic groups that occurred in Central Asia. However, despite its presumable importance, little is known about the level and the distribution of genetic variation in this region. We genotyped 26 Indo-Iranianand Turkic-speaking populations, belonging to six different ethnic groups, at 27 autosomal microsatellite loci. The analysis of genetic variation reveals that Central Asian diversity is mainly shaped by linguistic affiliation, with Turkic-speaking populations forming a cluster more closely related to East-Asian populations and Indo-Iranian speakers forming a cluster closer to Western Eurasians. The scattered position of Uzbeks across Turkic- and Indo-Iranian-speaking populations may reflect their origins from the union of different tribes. We propose that the complex genetic landscape of Central Asian populations results from the movements of eastern, Turkic-speaking groups during historical times, into a long-lasting group of settled populations, which may be represented nowadays by Tajiks and Turkmen. Contrary to what is generally thought, our results suggest that the recurrent expansions of eastern nomadic groups did not result in the complete replacement of local populations, but rather into partial admixture. European Journal of Human Genetics (2011) 19, 216–223; doi:10.1038/ejhg.2010.153; published online 8 September 2010