DNA Tests Have a Nasty Side Effect: Discovering Your Parents' Secrets

DNA tests promise to detail customers' ancestry — but in some cases, what the companies find is far more surprising than expected.

In a profile about unexpected DNA results, the BBC reported that an increasing number of ancestry test customers are learning that the people who raised them might not be their biological parents after all.

One woman, Kara Rubenstein Deyerin, grew up with a Black father and believed she was half-African-American herself. When she purchased at-home DNA tests for herself and her dad one Christmas to learn more about their cultures of origin, however, she received a shock with her own results: that she was half Ashkenazi Jewish, and had no African ancestry at all.

Rubenstein Deyerin's mother, it seems, had had sex with someone other than her father and it led to her birth.

"I'd never heard of the term Ashkenazi before. I didn't even think my mum had ever met a Jewish person before," she told BBC with a smile. "Obviously she did once."

Though she never met her biological father and his family wanted nothing to do with her, the woman ended up taking his last name, Rubenstein, as part of her own. She began learning more about her Jewish heritage and wearing a Star of David necklace, and traveled to Israel to get in touch with that previously unknown part of her.

The woman's discovery raises important questions about race and ethnicity, human-made categories that are subjective and change over time but that nevertheless have massive impacts on our lives.

Generally speaking, genetic ancestry companies like 23AndMe and AncestryDNA spend much time acknowledging the complicated nature of race and ethnicity in their marketing materials. A spokesperson for 23AndMe, however, did tell BBC that the company "does not conflate the concepts of ethnicity and genetic ancestry" and has "always understood the importance of distinguishing these concepts clearly."

Rubenstein Deyerin started an organization for people who learned they were a different ethnicity than the one they grew up claiming — people like Christine Jacobsen, who learned definitively that both of her parents were not Danish when she took her own at-home DNA test.

Jacobsen learned through the test that she was 25 percent West African, despite believing for most of her life that she was fully Danish.

"Clicking on the email and looking at the results was a validation of a question that I had had for all those 50 years," Jacobsen told the BBC.

Along with offering breakdowns of one's genetic background, sites like Ancestry.com and 23AndMe also allow users to get in contact with genetic matches who'd also used their service. Jacobsen contacted her first cousin and learned that her bio-dad was a dancer named Paul Meeres Jr, and ended up writing a memoir about her experience.

It's an ethically fraught and complicated debate. Jacobsen does still pass for white — another reason why some critics say that at-home DNA tests may complicate or confuse users' experiences with the culturally defined categories of race and ethnicity.

Mark Thomas, a professor of evolutionary genetics at Britain's University College London, told BBC that he's not a fan of the way these companies market using the term "ethnicity" because "your biological ancestry is not your ethnicity – ethnicity is a socially defined category."

"I feel that they are using the word as a euphemism for race," Thomas said. "Race is also socially constructed, but ideas about race traditionally were based more on ancestry. It just feels a bit icky – they are not biologically meaningful categories."

There's still a lot we all, collectively, must learn about race and ethnicity, both being very fraught and shifting categories, as these identifiers continue to play such massive roles in the way we interact with the world — and how they determine how the world interacts with us as a result.

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