Dolezal's delusion: Column Contrary to much of the racial identity debate, race is far from a social construct.

Alex Berezow and Razib Khan | USA TODAY

The saga of Rachel Dolezal, who recently resigned as president of the Spokane, Wash., chapter of the NAACP after it was revealed that she was dishonest about her racial identity, sparked yet another national debate on issues of race in America, until it was eclipsed by events in Charleston.

Though Dolezal's antics have garnered her few supporters, those sympathetic with her — primarily those on the left side of the political spectrum — insist that race is "just a social construct." That is biologically incorrect for two major reasons.

First, those who contend that Dolezal is perfectly free to identify as "black" are engaging in relativism — i.e., that each person is entitled to define truth as he or she sees it. That line of reasoning might work in sociology or the social sciences, but it does not work in genetics.

Second, the idea that race is either biological or sociological is a false dichotomy; it is manifestly both a biological and social construct. The relevant question, therefore, is: "To what extent does the biological factor matter?" Different geneticists give different answers. Some, such as Michael White and Alan Templeton at Washington University in St. Louis, say it doesn't matter at all and that race is not a biologically justifiable concept.

Others, however, argue that genetics still matters quite a bit. Genetic diseases tend to cluster among certain races and ethnicities. For instance, sickle cell anemia is found primarily among blacks, cystic fibrosis among whites of European descent, and Tay-Sachs disease among Ashkenazi Jews.

This is a reflection of the fact that human populations exhibit significant structure, which is a record of our history as a species.

It is widely accepted that the ancestors of the Khoisan hunter-gatherers of the Kalahari separated from the ancestors of the rest of humanity 150,000 years ago; ancestors of all non-Africans separated from Africans on the order of 50,000 years ago; and ancestors of Native Americans separated from East Asians 15,000 years ago. In some cases, diverged branches of this diversifying human tree came back together and fused to form new populations. All of these events have left distinct genetic markers.

In fact, as the famed biologist L. L. Cavalli-Sforza once stated, though our history as a species is short, there is more than enough genetic information to construct ancestral trees. And, genetics has the power to reveal much more about you than just your racial and ethnic identity.

For example, by sequencing just a small portion of DNA, scientists can detect your biogeographical ancestry and even get a rough estimate of what your face looks like.

The point is neither that genetics is fate nor that it determines everything about you. The environment also plays a significant role in developing the person you become, and that certainly includes racial identity.

But the history of human evolution, including race, is real, genetically traceable, and cannot be denied. Race, therefore, is a reflection of our history and geography. It is scientifically inaccurate to reduce human populations to mere social constructions and arbitrary crystallizations of power relations.

Rather, genetics compels us to view race and ethnicity as part of a larger journey that started with our first ancestors who evolved over the course of tens of thousands of years into the riotous colors and shapes that we recognize as human.

Alex Berezow , founding editor of RealClearScience , holds a PhD in microbiology, is a member of USA TODAY's Board of Contributors, and is co-author of Science Left Behind. Razib Khan is a PhD candidate in integrative genetics and genomics at University of California-Davis and a science writer who specializes in population genetics.

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