People prefer a good story, no matter what their DNA says

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In a paper published in the American Journal of Sociology, the researchers found that some people who have taken DNA tests from genealogy companies such as AncestryDNA and 23andMe selectively choose which results to adopt and share with others — including the government and its census — based on their aspirations and how they think other people will view their new identity.

"They're using it as a way to craft a new identity that they want to have," said Wendy Roth, the study's lead author and an associate professor of sociology at UBC.

One of the troubles with that, the researchers point out, is genetic tests aren't always accurate.

The researchers conducted in-depth phone interviews with 100 white, black, Hispanic/Latino, Asian and Native American participants in the U.S., all of whom underwent genetic testing, to see whether the results changed how they viewed themselves.

The study found 59 per cent of participants discovered new ancestry information but maintained their previous identities. However, 36 per cent incorporated at least some new racial or ethnic ancestry into their identity.

During interviews, the researchers found that of the people who took on new identities, most of them only chose some of the full range of possibilities identified by their genetic tests. 

One participant, for example, referred to in the study only as Eduardo, was identified before testing as a "non-Anglo white" with Native American ancestry, but his test results showed Celtic, Jewish and Native American ancestries. He embraced his Jewish heritage but didn't identify as Celtic. 

In his followup interview, he said he always looked up to his Jewish friends and neighbours and feels better now that he's one of them. 

UBC psychology professor Steven Heine, who wrote the book DNA Is Not Destiny and wasn't part of the study, said he's not surprised by the results. 

"People turn to ancestry testing to hopefully get a new story about their lives — one that they didn't necessarily know beforehand," Heine said in an email.

"Of course, people would prefer a good story, so if there are findings in their ancestry results that they like they'll probably emphasize those."

The study also found those who identified as only white before testing were the most likely to adopt new racial or ethnic identities, while those who identified as only black were least likely. 

"The white respondents were more likely to change their identity ... so they talked about how they wanted to be something different and they wanted to find something exotic or interesting that would make them a little special, a little unique," Roth said.

Consequences of cherry-picking

The researchers, who began their study in 2009, said cherry-picking new identities can have some serious consequences. They found that while not everybody changed their race or ethnicity, of the people who did, 82 per cent marked that new identity on the 2010 U.S. census.

"So if you end up with a lot of white people who now say, 'I now consider myself white and black. I now consider myself white and First Nation,' that means our statistics and our understanding of what are our populations in our society could very well be affected by this," Roth said.

Both Roth and Heine advise against putting too much faith in these genetic ancestry tests.

"They can be useful for certain things. For example, I've taken the tests myself and I've connected to some long-lost relatives and found out more about my family tree through the information that I've gotten from them," Roth said.

"But I think that taking tests thinking that I'm going to find out my race or ethnicity is the wrong way to go about it, and the tests are not going to tell you that."

Heine said the tests are probabilistic, not definitive and listed off several shortcomings:

• The database that they're based on isn't representative of the world. Many parts of the globe are under-sampled and that greatly reduces the precision.
• The industry is completely unregulated. The companies can tell you whatever they want.
• It's not uncommon for people to get different results from different companies even if the same genetic markers are identified. 

Heine said the search for our origins is a little misguided because if you trace back far enough you'll find a person who is the ancestor of everyone who's alive. 

"So if you go back far enough, we're all Chinese, Persian, Egyptian, Roman and so on," he said. "But that story isn't what most people are looking for — they're looking for a story that connects them to the past in a unique way."

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