Race isn’t a black and white issue.

Biologically, humans are 99.9 percent genetically identical, according to the Human Genome Project, completed in April 2003. A recent study by Northwestern University’s Center for the Study of Diversity and Democracy (CSDD) examined Americans’ perceptions and attitudes regarding race and genetics and found a more complex picture.

The survey, conducted in collaboration with DNA testing company 23andMe, found that 33.8 percent of Americans think biology totally determines racial identity; 18.8 percent think it somewhat determines race; 30.2 percent believe the two are related but not causal; 17.2 percent see no relation.

“I expected two-thirds of every population group would believe that science or biology determines your race. That was a huge surprise,” said Alvin Tillery Jr., director of CSDD. “Yet we still live in a society that demarcates us by race and that tiny, tiny sliver of our genetic code that is visibly different to others,”

To be clear, CSDD defines race as a construct that human beings use to organize themselves and others into groups. This construct often, but not always, relies on phenotypical or gross characteristics, also known as outward appearance.

The CSDD data, gathered from 3,000 adults this year, found white people to be the most committed to the idea that biology determines race (37.2 percent), followed by Latinos (27.1 percent), Asian-Americans (26 percent) and African-Americans (24.5 percent).

“To some extent, we can’t be too surprised by that,” Tillery said. “Study after study in race relations research show black Americans are the most committed to democratic personal choice — it’s this unwillingness to be defined by the system.”

Tillery explores the perceptions and the construct of race in his Northwestern Univeristy classes. He shows students a genomic pie chart representing someone who is 26 percent Scottish/Irish/U.K. and 74 percent West/Central Africa. He asks who they think the person is in the class. Most think the person must be able to pass for white. When it’s revealed that the genomic scan is Tillery’s, he said students are visibly shocked.

“The takeaway is we all got far more genetic complexity than we realize,” he said.

This is the second study that CSDD has conducted since opening 18 months ago — the first, in 2017, looked at how black Americans understand and perceive the Black Lives Matter movement. Both are collaborative projects that Tillery said follows the mission of the center, which is to strengthen a multiracial and gender-equitable democracy.

Another goal of this year’s survey was to gauge whether DNA tests make our existing perceptions of race better or worse.

The CSDD study this year found that about half of Americans think skin color is the best way to identify a person’s race; 35 percent think culture and history play a role; 18 percent believe race is a personal choice.

Tillery said the modern world is built on the misuse of these racial constructs to justify human rights violations (such as genocide, slavery and colonialism) and the extraction and transfer of resources from certain populations to others.

He mentioned scenarios in which white people, after discovering they have a 10 percent African genome, check the “person of color” box on elite college applications, believing that it’s easier to get accepted if you’re black or Latino.

“I don’t think we have thought about what possibilities there are, but we’ve certainly thought of the kind of situational identity problem in sociology where people choose what identity to stress as it suits their strategic and emotional goals,” Tillery said. “People getting these scans back may shift races for a variety of reasons, so that’s something that we definitely want to understand.”

Fifty-six percent of those polled said race relations are getting worse, not better. But whether DNA testing contributes to that decline, has not been proved, Tillery said. That’s a concept he said he would like to research next.

“When I did my ancestry test on Ancestry.com, they tell you who your closest kin who has also taken the test (is), and my closest kin is a white woman,” he said. “Genetically she and I have almost identical genomic scans. … We’ve known that these things can happen, but there’s never been a study to try to account for how the general population thinks about these issues. That’s what we’re doing with this project.”