U.S.-Russia-Mongolia Joint Collaborative Research: Comparative Framework for North Asian Genetic Diversity

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Hammer0216732This research will use human genomic variation patterns as a tool for testing hypotheses concerning the early peopling of North Asia and the Americas and for assessing the relative effects of sex-specific demographic processes and natural selection in shaping North Asian genetic diversity. Within genetics, the study of lineages that are inherited paternally, maternally or biparentally can offer different insights into the origins and global dispersals of Homo sapiens. The genetic analyses will be applied to a panel of 16 males from each of 6 Siberian populations. Comparisons of intra-specific patterns of variation within and among human populations, and with levels of divergence between humans and great apes at these loci, will enable tests of the effects of natural selection and potential differences in male and female effective population sizes. Informative polymorphisms discovered in this Siberian ascertainment panel will be genotyped in a larger set of North Asian samples to allow further tests of the associations between linguistic, geographic, and genetic variation and the effects of genetic drift, migration, and admixture on North Asian populations. These results will be used to aid in constructing more realistic colonization models involving different stages for the early peopling of the Americas.Results from this research will enhance our understanding of the evolutionary history of our species. Reconstructing the patterns and processes of human evolution in Asia is of interest because the the earliest dispersal routes of anatomically modern humans out of Africa are not well understood from the archaeological and paleontological records. Further, this region is the origin for subsequent migrations to Japan, Siberia, and the Americas. The 31 native ethnic groups of Siberia, 14 of which are available for this project, offer significant opportunities to examine the evolutionary forces that may have acted on early modern human populations. Until very recently many native Siberian groups retained traditional subsistence economies and lifeways that may have reflected a pre-Neolithic population structure. North Asian populations, especially those adapted to boreal climates in the northernmost regions inhabited by humans, are genetically subdivided, and genetic drift has played a key role in shaping patterns of variation in Siberia. Furthermore, the demographic history of Siberian populations has led to an unusually strong association between language and genetic variation. The proposed research is a first attempt to develop a comparative genetic framework using data obtained from the same set of samples.The proposed research will directly address three major challenges that now face anthropological geneticists. The multiple locus approach to be taken here will help to understand: (1) which portions of the human genome are variable; (2) how genomic and evolutionary processes have interacted to generate observed patterns of diversity; and (3) what the relative roles of each of these forces have been over different periods of time and in different populations. In addition to having a fascinating evolutionary history, Native Siberian populations represent an ideal model system within which to address these timely issues.