A Burst of Clues to South Asians’ Genetic Ancestry – The Atlantic

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The cities of the Indus Valley Civilization were cosmopolitan places, which also makes it harder to generalize from one genome. J. Mark Kenoyer, an anthropologist at the University of Wisconsin at Madison who was not an author of either study, cautions that only a small number of people who lived in these cities were buried in cemeteries—probably elites. The rest might have been cremated, or their bones simply left uncovered and thus scattered over time. “The cemeteries of the Indus civilization do not represent the people of the Indus civilization. They represent one community,” he says.

Still, more cemetery samples would be better than just one. The research team behind I6113 is trying to sequence more bones from the Indus Valley civilization. Vasant Shinde, an archeologist at Deccan College whose team excavated I6113, says the attempts to get ancient DNA from Indus Valley–civilization sites have been a years-long learning process. To prevent contamination with modern DNA, team members now wear gowns and masks even while excavating in the field. They do not reuse excavation instruments from burial to burial. Niraj Rai, a geneticist who was a visiting fellow in Reich’s lab, also set up an ancient-DNA lab at the Birbal Sahni Institute of Palaeosciences in Lucknow, India, where I6113’s DNA was extracted. “This is beginning,” Shinde says. “This is not the end.” He expects more ancient DNA to come.

In India, ancient DNA has generated intense interest, says Tony Joseph, the author of Early Indians: The Story of Our Ancestors and Where We Came From. He told me his book, published last December, is already in its seventh printing. After a preliminary version of the large Central and South Asian genomes study was posted on bioRxiv last March, it became the site’s most downloaded preprint of 2018. The preprint generated controversy, too, especially the finding that many Indians have ancestry from steppe pastoralists. Hindu nationalists, as Joseph has written, believe that Aryans—who originated in India and spread through Europe and Asia—are the source of Indian civilization. This is contradicted by ancient DNA that finds the population history in India itself contains far more mixing and migration. (Further complicating things, Nazis co-opted the term Aryans to mean something different, a master race of European origin.) A prominent MP even attacked Reich when the preprint came out, tweeting out an article titled, “There Are Lies, Damned Lies and (Harvard’s ‘Third’ Reich and Co’s) Statistics.” Reich, who has experienced how fraught talking about genetics and identity can be, acknowledged the political interest in his work, but declined to get into it.

Ancient DNA has captured the public imagination precisely because it promises an answer to questions like Where did we come from? and Who are we?—questions that also have deep political undercurrents. To sequence I6113’s DNA is to draw genetic connections between an ancient civilization and the people who live in the region today, to add fuel to arguments about who can lay claim to a cultural inheritance. All this, contained in a half-inch wisp of an ear bone.

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is a staff writer at The Atlantic.