What Consumers Need to Know About Home Genetic Tests

False positives can lead to real anxiety for at-home genetic test users.

Direct-to-consumer (DTC) genetic tests are popular choices for people interested in learning more about their ancestries—including the identification of relatives—but problems can arise when consumers turn to DTCs for health information, which can often end with incorrect results.

“A recent study found that about 40 percent of the results that tell people they have a genetic disorder are false positives,” James genetics expert Heather Hampel, MS, CGC, says.

Though there are some DTC companies that offer medical-grade genetic testing for conditions such as cancer and high cholesterol, Hampel believes the highly-complicated work of interpreting and understanding the results should become part of regular, in-person interactions between patients and their healthcare providers.

“I saw a patient this spring who was told she had two mutations that could cause a health condition. One caused Lynch syndrome, the most common inherited form of colon and endometrial cancer. The other was for an inherited,” Hampel says. “She had no family history, so it wasn’t making sense, and so she came in and saw me. She was negative and didn't have either condition, which was a huge relief. But she went through quite a scare.” While such false positives can cause serious anxiety, it’s the possibility of the opposite that is of particular concern to Hampel.

“There hasn’t been any research on this yet, but down the road, we could see incidences of people who were given negative results from these DTC genetic tests who do in fact have a genetic mutation,” she says. “This is why it’s so important to talk to your primary care physician about your family history and see a genetic counselor if warranted and get a medical-grade genetic test.”