Nearly Half of At-Home DNA Test Results Could Be Wrong

Update |

At-home DNA tests are "not intended for medical use," meaning that the data they give you shouldn't be used as a replacement for a real medical diagnosis.

At-home genetic testing companies like 23andMe,, Family Tree DNA and My Heritage are gaining popularity as a relatively cheap way to understand one's ethnicity and genetic history.

Yet new research suggests that some results identifing genetic issues may be innaccurate—and that as much as 40 percent of analyses of these at-home genetic tests implying genetic disorders could be innacurate.

Researchers at AmbryGenetics conducted a study of 49 individuals who had done "direct-to-consumer" DNA tests who then sent their genetic results to third parties for analysis. AmbryGenetics then checked those analyses with a more detailed and expensive genetic test. They found that only 60 percent of the genetic variance results could be confirmed.

While this is a relatively small sample of 49 people, the thirteen results that came from the company 23andMe were confirmed accurate. In an email to Newsweek, they noted that their product "undergoes an incredibly rigorous, FDA-mandated accuracy review process - much more rigorous than this study which only used 49 samples from several different companies, whereas we test hundreds of samples."

An illustration of human DNA. Pixabay

The study was published Monday in the journal Nature.

Companies often send back raw data containing a complicated list of gene abnormalities that can imply that a person is more likely to have a disorder. The FDA said that they can't advertise as a way to diagnose diseases, but 23andMe specifically has permission to market genetic health risk tests for certain conditions.

Some companies simply offer the raw DNA data for their customers to do what they like with it. That data comes with a disclaimer that the results are not verified for accuracy.

The authors of the study noted that reading false results about genetic disorders could lead to people taking better preventative care of themselves, but also might create needless anxiety over a nonexistent issue for them. The authors wrote that it was important for doctors to order tests that truly confirmed a condition before treating it.

This article has been updated with information from 23andMe.