Genetic diversity in India and the inference of Eurasian population expansion.

TitleGenetic diversity in India and the inference of Eurasian population expansion.
Publication TypeJournal Article
Year of Publication2010
AuthorsXing, J, W Watkins, S, Hu, Y, Huff, CD, Sabo, A, Muzny, DM, Bamshad, MJ, Gibbs, RA, Jorde, LB, Yu, F
JournalGenome Biol
Date Published2010
KeywordsDNA, Mitochondrial, Ethnic Groups, Gene Frequency, Genetic Variation, Genetics, Population, Geography, Humans, India, Polymorphism, Single Nucleotide, Population Density, Population Dynamics, Sequence Analysis, DNA

BACKGROUND: Genetic studies of populations from the Indian subcontinent are of great interest because of India's large population size, complex demographic history, and unique social structure. Despite recent large-scale efforts in discovering human genetic variation, India's vast reservoir of genetic diversity remains largely unexplored.RESULTS: To analyze an unbiased sample of genetic diversity in India and to investigate human migration history in Eurasia, we resequenced one 100-kb ENCODE region in 92 samples collected from three castes and one tribal group from the state of Andhra Pradesh in south India. Analyses of the four Indian populations, along with eight HapMap populations (692 samples), showed that 30% of all SNPs in the south Indian populations are not seen in HapMap populations. Several Indian populations, such as the Yadava, Mala/Madiga, and Irula, have nucleotide diversity levels as high as those of HapMap African populations. Using unbiased allele-frequency spectra, we investigated the expansion of human populations into Eurasia. The divergence time estimates among the major population groups suggest that Eurasian populations in this study diverged from Africans during the same time frame (approximately 90 to 110 thousand years ago). The divergence among different Eurasian populations occurred more than 40,000 years after their divergence with Africans.CONCLUSIONS: Our results show that Indian populations harbor large amounts of genetic variation that have not been surveyed adequately by public SNP discovery efforts. Our data also support a delayed expansion hypothesis in which an ancestral Eurasian founding population remained isolated long after the out-of-Africa diaspora, before expanding throughout Eurasia.

Alternate JournalGenome Biol.
PubMed ID21106085
PubMed Central IDPMC3156952
Grant ListDK069513 / DK / NIDDK NIH HHS / United States
5U54HG003273 / HG / NHGRI NIH HHS / United States
U54 HG003273 / HG / NHGRI NIH HHS / United States
R01 GM059290 / GM / NIGMS NIH HHS / United States
U01HG005211-01 / HG / NHGRI NIH HHS / United States
K99HG005846 / HG / NHGRI NIH HHS / United States
GM-59290 / GM / NIGMS NIH HHS / United States