Finding family ties through DNA testing

Have you ever done a direct-to-consumer (DTC) genetic test, such as 23andMe or AncestryDNA? If so, you’re part of a community of tens of millions of people who’ve used these tests to try to understand more about their family, their health risks, or to track down biological relatives.

Now, a new study by US-based researchers has examined the experiences of people using DTC genetic testing for genetic genealogy – the field of using DNA to understand your family history and relationships – discovering that the identification of new genetic relatives through DNA testing is now commonplace.

This is how it usually works: you buy a DTC genetic test, provide a sample (usually saliva), and send it off to the company to have your DNA extracted and sequenced. Then they send you a report on your DNA profile, with varying levels of detail.

If you’re looking for relatives, the next step is to share your DNA data with a genetic relative-finder service. Many of these are run by the same companies that do the DTC testing.

The genetic relative-finder service compares your DNA to that of other users in its database to identify those who are likely to be related, and provides you with a way to contact each other.

“We’ve been paying attention to stories in the media about individuals who’ve made surprising family discoveries from these tests and relative-matching services,” says lead author Christi Guerrini of the Center for Medical Ethics and Health Policy at Baylor College of Medicine in Houston, Texas, US.

“We wanted to understand if these and other kinds of discoveries are common, how they’re experienced by those making the discoveries, and what people are doing as a result.”

The researchers surveyed over 23,000 users of DTC genetic testing and genetic genealogy services. They asked why people had engaged with the testing, whether they had found any previously unknown relatives, and the impact this discovery had on them.

“It seems that many – perhaps most – are just curious about their families and interested in building out their family trees, but it’s clear that quite a lot of participants are looking for someone or hoping to confirm something in particular,” says Guerrini.

“It might be that they’re adopted and looking for a biological parent, or that they’ve always felt out of place in their family and want to see if there’s something to that feeling.

“Or they might be looking for information about a branch of their family tree that’s unknown to them, or to confirm a family story that’s been passed down over the years.”

The majority of respondents (82%) did identify at least one genetic relative, and 61% said they learned something new about themselves or their relatives.

For most, the experience of participating in genetic genealogy was positive or neutral, and relatively few regretted taking part in the test.

However, a minority of respondents reported strongly negative outcomes. These were most common when people discovered that a parent was not their biological parent, and in people who were donor-conceived.

“When I first learned via a DNA test that my daddy was not my father, I had a nervous breakdown… After the initial trauma, I determined to learn all that I can about genetics and to help other people in a similar situation,” said one study participant quoted in the paper.

“In future research, we’d like to better understand those [negative] outcomes and what resources could be helpful in managing them,” says Guerrini.

Most respondents in the study self-identified as white and reported high levels of education and income, consistent with the profile of people more likely to engage in DTC genetic testing.

The research team hopes to continue investigating complex experiences of people who have used these services.