You collected your saliva and mailed it off to the testing company. Today’s the day you’ve been waiting for: The link to your DNA results are in your in-box! But your excitement is soon replaced with anxiety as you try to decipher a litany of genetic health risks. What does it all mean? Genetic counselor Leigha Senter helps you sort it out.
Home genetic test kits like the heavily-advertised AncestryDNA and 23andMe are becoming big businesses, with sales approaching $100 million in 2017. For less than $200 (in some cases, much less), you can now have your DNA analyzed without a doctor’s order or the expense of going to a genetics center.
Just how extensive can the testing be? Depending on the kit, the results can uncover everything from how you metabolize your morning coffee to where your distant relatives came from. 23andMe, for instance, allows you to buy genetic health risk reports to see if you have gene variants (changes) associated with a handful of hereditary medical problems ranging from certain cancers to Parkinson’s and Alzheimer’s as well as some BRCA 1 and 2 mutations. You can also find out if you’re a carrier of more than 40 serious genetic diseases that could put a future baby at risk if the other parent is a carrier, too. The test also reports on certain traits, such as earwax type and eye color, and wellness issues such as genetic markers for lactose intolerance.
Many testing companies let you take results one step further—you can download your raw DNA data and then upload it to a third-party service to interpret more about your possible genetic health risks.
This is where it can get really dicey. The raw data from a home test is not validated for accuracy, and some of the databases used by third-party companies are not always up to date. Combined, these flaws can lead to identifying issues in the raw data that aren’t necessarily there.
Further, sometimes your at-home genetic test result doesn’t tell the whole story. For example, you may think you’re in the clear because you didn’t have mutations in the “cancer genes” that were included on your test, but maybe the test wasn’t comprehensive and depending on your family history, you could still have an elevated cancer risk that would be best managed by increased screening.
A report published in the journal Translational Behavioral Medicine highlights the problem this poses for home-test customers and health professionals alike. More than half of the 85 genetic counselors surveyed said they had been contacted by people who used a third-party interpretation service. Counselors gave the reports a “poor” rating for clarity and informativeness, aspects that often left patients confused and frustrated and left the counselors trying to explain results to them.
The researchers called for government oversight and regulation of these third-party services, but that doesn’t help you today as you’re staring at your report.
WHAT YOU SHOULD KNOW AND DO
If you learned from either the initial home report or the third-party report that you tested positive for a gene variant associated with a health condition, take a deep breath. It doesn’t necessarily mean you have the condition or are doomed to get it because so many other factors might come into play–family history, diet, your weight and lifestyle choices—in the development of a disease. And it’s important to keep in mind that if you find out you have a high or almost certain risk of developing some health problem or condition, there may be things you can do to change that risk. Getting all of the facts from a professional is important.
On the other hand, if you test negative, that doesn’t necessarily mean you’re in the clear. The tests don’t always screen for every variant that can cause a particular disease. For instance, the 23andMe test now has government approval to report on mutations in the BRCA genes. But the company tests for only three out of hundreds of known mutations. You still could have one of the others that puts you at greater risk for cancers associated with those mutations. So, medical decisions shouldn’t be made based on the results of an at-home test alone.
Meet with a genetic counselor: If your health report or raw data shows a gene variant that concerns you, a genetic counselor should be able to explain your real risk (if any) or, if it’s the case, to explain that your real risk can’t be determined by the data. Sometimes, further testing in a clinical setting is necessary to sort it out. This kind of testing is often more reliable than an at-home test. Another reason you may want a clinical test is if your home DNA test shows no variations but you know that you have a strong family history of a medical condition. You can look for a genetic counselor to contact in person or by phone here.
Talk to your doctor: Share the results of your home test and your family history with your healthcare provider. If you’re at higher risk for a hereditary condition, ask about how to catch it early or prevent it in the first place, such as by changing your diet or getting more exercise. Depending on the condition, steps may include additional or more frequent screenings/tests, medication or even preventive surgery.
Know what to share with family: If you’re at high risk for a hereditary illness, your blood relatives could be, too. If you haven’t already spoken with your family members about whether they want to know your results, now is the time. Respect each person’s decision—some people would rather not know, especially if it involves a condition for which there are no preventive steps to take.
Important: If you’re doing testing to learn more about your ancestry rather than health issues, or you decide you’re not ready to learn whether you could have a high risk of, say, Alzheimer’s or Parkinson’s disease, 23andMe gives you the option to not view those reports. If you decide to find out later, you can view them by changing your account settings.
Know the insurance ramifications: By law, genetic information can’t be used to discriminate against you for health insurance or employment. But the legal protections do not extend to life, disability or long-term care insurance. These insurers could use your results to set your premiums or choose not to cover you at all. You may be asked about DNA testing and results directly on the application. The insurer may see your test results in your medical records or the agent may take note of extra health screenings or other preventive measures you’re taking—even if he/she doesn’t know about the testing directly.