From Nature:
Now, a team led by David Reich of the Broad Institute in Cambridge, Massachusetts, and Lalji Singh of the Centre for Cellular and Molecular Biology in Hyderabad, India, has probed more than 560,000 SNPs across the genomes of 132 Indian individuals from 25 diverse ethnic and tribal groups dotted all over India. The researchers showed that most Indian populations are genetic admixtures of two ancient, genetically divergent groups, which each contributed around 40-60% of the DNA to most present-day populations. One ancestral lineage — which is genetically similar to Middle Eastern, Central Asian and European populations — was higher in upper-caste individuals and speakers of Indo-European languages such as Hindi, the researchers found. The other lineage was not close to any group outside the subcontinent, and was most common in people indigenous to the Andaman Islands, a remote archipelago in the Bay of Bengal.
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