This news item republished at the genetics blog, Gene Expression, is likely to have some impact in India, where there’s been a long-standing debate about the North Indian-South Indian divide, also known as the Aryan-Dravidian divide.

There are several theories about the origin of the different peoples of India. The most popular one and the one that’s favored by the most prominent historians is the Aryan invasion theory.This theory suggests that there was a substantial difference between a preexisting population of shorter, darker people in South India (called Dravidians) and an invading bronze- age culture of taller, fairer people (Aryans) that brought in Vedic or Hindu culture.

This theory, of course, has had a lot of repercussions not only for history and anthropology, but also for politics. The Aryan invasion theory depicts Hindu culture as having a foreign origin, so it was considered colonial, if not racist, by many Indian scholars.

Anthropologists consider Indians to be a branch of a widely dispersed Indo-European group that sent out branches to Persia (Indo-Iranian), Europe (Indo-European) and India (Indo-European). Race theories that developed in the 19th century tended to use this Aryan theory as their foundation (if I’m not mistaken).

However, many Hindu nationalists have considered the Aryan invasion theory a colonial distortion and have argued instead that the movement of people was in the opposite direction. In other words, the Aryans moved outward from India. This would make India the mother culture of the Aryans

Critics of this Indian origin theory call it an outgrowth of Hindu chauvinism. The debate has been a pretty heated one, as a consequence.

Now comes new research.

The Times of India notes:

“The great Indian divide along north-south lines now stands blurred. A pathbreaking study by Harvard and indigenous researchers on ancestral Indian populations says there is a genetic relationship between all Indians and more importantly, the hitherto believed “fact” that Aryans and Dravidians signify the ancestry of north and south Indians might after all, be a myth.

“This paper rewrites history... there is no north-south divide,” Lalji Singh, former director of the Centre for Cellular and Molecular Biology (CCMB) and a co-author of the study, said at a press conference here on Thursday.

Senior CCMB scientist Kumarasamy Thangarajan said there was no truth to the Aryan-Dravidian theory as they came hundreds or thousands of years after the ancestral north and south Indians had settled in India.

The study analysed 500,000 genetic markers across the genomes of 132 individuals from 25 diverse groups from 13 states. All the individuals were from six-language families and traditionally “upper” and “lower” castes and tribal groups. “The genetics proves that castes grew directly out of tribe-like organizations during the formation of the Indian society,” the study said. Thangarajan noted that it was impossible to distinguish between castes and tribes since their genetics proved they were not systematically different.

The study was conducted by CCMB scientists in collaboration with researchers at Harvard Medical School, Harvard School of Public Health and the Broad Institute of Harvard and MIT. It reveals that the present-day Indian population is a mix of ancient north and south bearing the genomic contributions from two distinct ancestral populations – the Ancestral North Indian (ANI) and the Ancestral South Indian (ASI). ”