At Home DNA Tests: Are They a Reliable Method for Cancer Screening?

Categories: Genetic Testing

October 1, 2018

Up until recently, genetic testing for cancer had to be performed by a medical professional – but that’s not the case anymore. Today, people concerned about their genetic health risks can have their DNA analyzed for health reasons, in the comfort of their own home.

23andMe, the company known for its spit-and-mail ancestry test, now offers FDA-approved genetic tests for cancer, which can be mailed directly to consumers. While there are other at-home genetic tests available, 23andMe is the first company that can offer this kind of testing without a doctor’s order.

But is at-home testing for cancer -- or any hereditary disease for that matter -- a good idea?

The concept, of course, sounds appealing. Home DNA tests offer convenience, affordability, and privacy, so it’s no surprise that people are interested in testing themselves. But using a product such as this for health-related reasons is much trickier than using it to determine your family roots.

Helpful or Harmful?

Although these tests may be able to provide you with valuable information regarding your risk for getting cancer or other diseases, the results can be misleading, hard to interpret, and downright overwhelming. For example, your at-home genetic test results may show that you have a certain gene mutation--but will it be clear as to whether this particular mutation actually raises your cancer risk and by how much?

Additionally, tests like this are very limited in scope. In the case of 23andMe, it only tests for three mutations found in the BRCA1 and BRCA2 genes, which are linked to breast and ovarian cancer, leaving out the thousands of other mutations that increase the risk for those, as well as other types of cancer.

Not All Genes (or Genetic Tests) are Created Equal

When it comes to determining your risks for developing cancer, it’s important to remember that not all genes are created equal. While one gene may increase your risk by a small percentage, another gene may increase it by a much greater percentage.

Genetic tests aren’t created equal either. What you may not realize, is that at-home DNA tests usually only look for one or two of the most common gene mutations linked to a hereditary disease. If you are looking for a specific gene change, how can you be certain it was the one that was tested? The test may say that you aren’t at risk, but in reality, all that really means is that you’re not a carrier for the one or two mutations they looked for.

This is why genetic testing is best done through a professional, no matter how convenient and affordable an at-home test may be. The only way to ensure more accurate results, and a better understanding of those results, is by visiting a doctor who works with specially-trained genetic counselors. A genetic counselor can guide you every step of the way, addressing any questions or concerns you may have regarding your results.

Genetic testing is not for everyone, so it is important to talk with your doctor or a genetic counselor to determine if you would be a good candidate for it. If you are located in the Portland, OR or Vancouver, WA areas you can schedule an appointment at Compass Oncology to talk to someone about a genetic risk evaluation and testing, along with counseling. Even if genetic testing isn’t for you, it is important to see your doctor to find out what other types of cancer screening you can benefit from.