There is a long and troubling history of science – or at least pseudoscience – being used to justify racism and discrimination. The nineteenth century practice of phrenology is a commonly cited – and thoroughly debunked – example.
But in the 1970s, the emerging field of genetics began presenting evidence against a biological definition of race and that has become the scientific consensus.
Still, it is increasingly clear that there are genetic differences that do correlate with populations that were separated for thousands of years by mountain ranges or oceans.
Cystic fibrosis is most common among those of northern European descent, prostate cancer is more prevalent in men of Western African descent, and Tay-Sachs disease disproportionately affects Ashkenazi Jewish populations.
David Reich is a geneticist at Harvard University whose research is completely predicated on there being genetic differences between populations.
He uses those differences to trace the migration of humans around the globe over the past five millennia, and he’s worked many of those stories into his new book Who We Are and How We Got Here.
While much of his research looks at the past, he also has his eye on our present-day and even future discussions about race and he argues that we urgently need a new, open and accurate way to talk about these genetic differences that doesn’t open the door to racism.
“Race, as we’ve known for many decades, is a socially constructed category,” he told Living Lab Radio. “It corresponds to ideas about how to place people into groups that have changed over time from U.S. Census to U.S. Census.”
For example, the category of “white” doesn’t reflect a genetic group that’s been around for tens of thousands of years. Rather, within the last 5,000 to 10,000 years, there were four distinct genetic groups living in Europe that were as different from each other as East Asians are from Europeans today.
“Almost every assumption that we’ve had about [racial] differences has been exploded,” through his work over the last decade, Reich said.
But even though there’s not one “white” or “black” race, we will likely find more differences between geographically separated populations as the work on genetics continues. Reich argues that geneticists need to be at the forefront of the conversation.
“Because geneticists have not been providing a lot of guidance… that space gets filled with… people who say that the stereotypes have been correct all along.”