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White? Black? A Murky Distinction Grows Still Murkier

In 1924, the State of Virginia attempted to define what it means to be white.

The state’s Racial Integrity Act, which barred marriages between whites and people of other races, defined whites as people “whose blood is entirely white, having no known, demonstrable or ascertainable admixture of the blood of another race.”

There was just one problem. As originally written, the law would have classified many of Virginia’s most prominent families as not white, because they claimed to be descended from Pocahontas.

So the Virginia legislature revised the act, establishing what came to be known as the “Pocahontas exception.” Virginians could be up to one-sixteenth Native American and still be white in the eyes of the law.

People who were one-sixteenth black, on the other hand, were still black.

In the United States, there is a long tradition of trying to draw sharp lines between ethnic groups, but our ancestry is a fluid and complex matter. In recent years geneticists have been uncovering new evidence about our shared heritage, and last week a team of scientists published the biggest genetic profile of the United States to date, based on a study of 160,000 people.

The percentage of self-identified European Americans who have one percent or more of African ancestry. Credit 23andMe
The researchers were able to trace variations in our genetic makeup from state to state, creating for the first time a sort of ancestry map.

“We use these terms — white, black, Indian, Latino — and they don’t really mean what we think they mean,” said Claudio Saunt, a historian at the University of Georgia who was not involved in the study.

The data for the new study were collected by 23andMe, the consumer DNA-testing company. When customers have their genes analyzed, the company asks them if they’d like to make their results available for study by staff scientists.

Over time the company has built a database that not only includes DNA, but also such details as a participant’s birthplace and the ethnic group with which he or she identifies. (23andMe strips the data of any information that might breach the privacy of participants.)
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