Basu et al. (2003) suggests concludes that "Dravidian tribals were possibly widespread throughout India before the arrival of the Indo-European-speaking nomads" and that "formation of populations by fission that resulted in founder and drift effects have left their imprints on the genetic structures of contemporary populations".[37] The geneticist PP Majumder (2010) has recently argued that the findings of Reich et al. (2009) are in remarkable concordance with previous research using mtDNA and Y-DNA:[44]
Central Asian populations are supposed to have been major contributors to the Indian gene pool, particularly to the northern Indian gene pool, and the migrants had supposedly moved into India through what is now Afghanistan and Pakistan. Using mitochondrial DNA variation data collated from various studies, we have shown that populations of Central Asia and Pakistan show the lowest coefficient of genetic differentiation with the north Indian populations, a higher differentiation with the south Indian populations, and the highest with the northeast Indian populations. Northern Indian populations are genetically closer to Central Asians than populations of other geographical regions of India... . Consistent with the above findings, a recent study using over 500,000 biallelic autosomal markers has found a north to south gradient of genetic proximity of Indian populations to western Eurasians. This feature is likely related to the proportions of ancestry derived from the western Eurasian gene pool, which, as this study has shown, is greater in populations inhabiting northern India than those inhabiting southern India.