July 29, 2004

mtDNA in Maharashtra (India)

A new study examines mitochondrial diversity in the population of Maharashtra (India) and confirms the authochthonous development of mtDNA haplogroup M in India, and finds that the indigenous clades U2 and U7 are the most important subclades of U in this population. The coalescence age for M is ~45000 ± 641 and for U it is ~25600 ± 1624. According to the authors, these results demonstrate that:

Thus, this reconfirms that India has witnessed two major expansion phases that have influenced the wide assortment of the Maharshtrian and other Indian lineages. The more recent phase, which according to our estimation started around 25600 years ago, is well reflected in the coalescence age of U. This period seems to correspond to the transition from the Middle to the Upper Paleolithic. The first expansion phase may reflect a demographic burst immediately after the initial peopling of India around 45000 years ago.
Annals of Human Genetics
OnlineEarly doi:10.1046/j.1529-8817.2004.00108.x

Mitochondrial DNA Diversity in Tribal and Caste Groups of Maharashtra (India) and its Implication on Their Genetic Origins

M. M. Baiga et al.


Genetic relationships among caste-groups are not uniform across the geographical regions of India. Many anthropologists have speculated on the tribal origin of some caste groups in Maharashtra and other states of India. To test this hypothesis, we used neutral mtDNA markers to study genetic relatedness among tribal and caste groups from Maharashtra. Descriptive statistics such as nucleotide diversity, gene diversity and average mismatches were found to be of the same magnitude. Phylogenetic network analysis exhibited a star-like expansion that may date back to the peopling of Eurasia, ~50,000 year ago. The reconstruction of mtDNA haplogroups showed that both the caste and tribal populations share similar branches of the tree. Also, the coalescence age estimation of caste and tribal populations suggests the persistence of maternal lineages with their root in early late Pleistocene. Our mtDNA analyses show some preliminary and significant evidence for the origin of prehistoric tribal and hierarchical caste societies of Maharashtra.


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