Population genetic structure in Indian Austroasiatic speakers: the role of landscape barriers and sex-specific admixture.
The geographic origin and time of dispersal of Austroasiatic (AA) speakers, presently settled in south and southeast Asia, remains disputed. Two rival hypotheses, both assuming a demic component to the language dispersal, have been proposed. The first of these places the origin of Austroasiatic speakers in southeast Asia with a later dispersal to south Asia during the Neolithic, whereas the second hypothesis advocates pre-Neolithic origins and dispersal of this language family from south Asia. To test the two alternative models, this study combines the analysis of uniparentally inherited markers with 610,000 common single nucleotide polymorphism loci from the nuclear genome. Indian AA speakers have high frequencies of Y chromosome haplogroup O2a; our results show that this haplogroup has significantly higher diversity and coalescent time (17-28 thousand years ago) in southeast Asia, strongly supporting the first of the two hypotheses. Nevertheless, the results of principal component and "structure-like" analyses on autosomal loci also show that the population history of AA speakers in India is more complex, being characterized by two ancestral components-one represented in the pattern of Y chromosomal and EDAR results and the other by mitochondrial DNA diversity and genomic structure. We propose that AA speakers in India today are derived from dispersal from southeast Asia, followed by extensive sex-specific admixture with local Indian populations.
Department of Evolutionary Biology, Institute of Molecular and Cell Biology, University of Tartu and Estonian Biocentre, Tartu, Estonia.
Gyaneshwer
G
Chaubey
Mait
M
Metspalu
Ying
Y
Choi
Reedik
R
Mägi
Irene Gallego
IG
Romero
Pedro
P
Soares
Mannis
M
van Oven
Doron M
DM
Behar
Siiri
S
Rootsi
Georgi
G
Hudjashov
Chandana Basu
CB
Mallick
Monika
M
Karmin
Mari
M
Nelis
Jüri
J
Parik
Alla Goverdhana
AG
Reddy
Ene
E
Metspalu
George
G
van Driem
Yali
Y
Xue
Chris
C
Tyler-Smith
Kumarasamy
K
Thangaraj
Lalji
L
Singh
Maido
M
Remm
Martin B
MB
Richards
Marta Mirazon
MM
Lahr
Manfred
M
Kayser
Richard
R
Villems
Toomas
T
Kivisild
D001210:Asia, Southeastern; D041322:Chromosomes, Human, Y; D004272:DNA, Mitochondrial / Q000235:genetics; D004641:Emigration and Immigration; D014644:Genetic Variation; D005828:Genetics, Population; D006801:Humans; D007194:India; D007802:Language
D004272:DNA, Mitochondrial