Indians are genetically distinct
In a study published online in the journal PLoS Genetics, a peer-reviewed journal published by the Public Library of Science (PLoS), Patel and colleagues analyzed 1,200 genome-wide polymorphisms collected from 432 individuals representing 15 different Indian populations.
This study represents the largest study of Indian genetic variation performed to date, in terms of the total number of sites in the human genome that were surveyed.
The researchers found that populations from India, and more generally, South Asia, make up one of the major human ancestry groups, with relatively little genetic differentiation among the Indian populations. Although the study used participants that may not reflect a random sample from India, these results still suggest that the frequencies of many genetic variants are distinctive in India compared to other parts of the world.
"We were struck both by the low level of diversity amongst people spanning such a large geographical region, and by the fact that people of the Indian sub-continent constituted a distinct group when compared to populations from other parts of the world," says Patel.
Her group is using this study as a foundation for future studies on the genetic basis of various common diseases in Asian Indians-such as heart disease, which is highly prevalent in this population.
Low Levels of Genetic Divergence across Geographically and Linguistically Diverse Populations from India