2007 Peopling of South Asia: investigating the caste-tribe continuum in India

In recent years, mtDNA and Y chromosome studies in-volving human populations from South Asia and the rest of the world have revealed new insights about the peopling of the world by anatomically modern humans during the late Pleistocene, some 40,000–60,000 years ago, over the southern coastal route from Africa. Mole-cular studies and archaeological record are both largely consistent with autochthonous differentiation of the genetic structure of the caste and tribal populations in SouthAsia. High level of endogamy created by numerous social boundaries within and between castes and tribes, along with the influence of several evolutionary forces such as genetic drift, fragmentation and long-term iso-lation,haskept the Indianpopulationsdiverseanddistant from each other as well as from other continental popu-lations. This reviewattempts to summarize recent genetic studies on Indian caste and tribal populations with the focus on the information embedded in the socially defined structure of Indian populations. BioEssay