Is It Harmful to Know Too Much About Your DNA?

Last year, the market for home DNA testing products totaled $99 million, a figure that’s expected to more than triple by 2022. The companies that provide these products are an outgrowth of a comprehensive long-term scientific effort, involving researchers from around the world, to sequence the human genome which was a project started in 1990. Today, there are plenty of opportunities to have your DNA tested and analyzed, ranging from medically supervised tests done under the care of your doctor, to companies that advertise their products online and on TV, offering insights into your health and ancestry based on your DNA.

But just because you can have your DNA tested, does that mean you should? Recent studies conducted at Yale University have shown that knowing about your genes could lead you to make health decisions that aren’t in your best interests.

In one study, a group of participants were informed that their genetic profile would be evaluated to determine if they were at risk for depression. They were then told that they were, in fact, at a higher risk for depression, even though their DNA was not actually tested. The participants later reported experiencing symptoms of depression at a higher-than-normal rate, despite the results being randomly made up.

In the other study, also conducted at Yale by the same researchers, a group of individuals were told that they were not genetically predisposed to obesity, while others were not given the same information. Again, these results were not factual; they were made up by the researchers. The follow-up results showed that these participants were more likely to make unhealthy choices when it comes to diet and exercise.

It’s important to note that at the end of the study, the researchers told the participants that the test results they were given were fake. All of the research and the methodologies were approved by an ethics review board at Yale.

Other concerns about genetic testing

In addition to concerns about knowing too much about your genetic makeup, it’s also important to distinguish between the kind of genetic testing that occurs in a hospital setting or doctor’s office, and the at-home kind you see advertised everywhere online and on television.

Recently, the U.S. Senate Special Committee on Aging concluded that the home tests can be inaccurate or misleading, as well as overly broad, making recommendations that could apply to just about anyone. Their report also cited experts who say links between specific genetic mutations and most diseases are, as yet, unproven. In fact, the Food & Drug Administration has only approved about a dozen genetic tests out of the thousand or so currently available on the market, and some of them are of the “at-home” variety.

Finally, there are some non-medical concerns about at-home DNA tests, arising because of the genetic data you give them. That leads to questions about whether they might sell your genetic data to third-party companies, which would be a privacy concern for many people. Genetic testing can also reveal unexpected information about the relationships in your family. 

So if you should decide to purchase one of these kits, read the fine print to make sure your info isn’t going to be sold to the highest bidder. Also, be skeptical of any home testing company that provides you with results, then tries to sell you vitamins or other products that they say can prevent whatever they found in the test.

These tests may reveal information that is difficult to understand. A genetics expert can help clarify the information or help you determine the appropriate genetic testing. You can use the National Society of Genetic Counselors’ “Find a Genetic Counselor” search tool in order to find a genetic counselor that specializes in the area of your concern.