By SMH Genetic Counselor Nicole Wood
You may have seen advertisements for at-home genetic tests on television or the Internet. These direct-to-consumer (DTC) kits, which have been on the market for a decade, have historically been frowned upon by both medical doctors and regulatory committees like the U.S. Food and Drug Administration (FDA). But just this past April, the FDA gave a private company the go-ahead to market DTC genetic test kits that claim to provide genetic-risk information for 10 hereditary health conditions, including Parkinson’s, Celiac and late-onset Alzheimer’s disease.
In the wake of the FDA’s approval, it’s important that potential buyers understand a little background about the DTC tests and how they differ from the genetic testing and counseling services that medical professionals can provide.
Understanding Genetic Testing
Genetic testing is typically ordered by a physician or genetic counselor to investigate how likely it is that you will develop specific hereditary diseases. Advancements in genetics and technology have made genetic testing available without a doctor’s order, and now, businesses can sell genetic-test kits online and can deliver them directy to your door. The allure of these convenient DIY kits is obvious, and they might provide some interesting information, but are the results useful?
A genetic counselor’s job is to be the expert on all things “genetic” and to ensure that you understand your genetic testing options and exactly what the results mean for you and your family’s health. These genetics experts often will start pre-test counseling sessions, explaining what the risk-assessment tests are looking for.
Humans have more than 20,000 genes. These genes are like a set of instructions for making each person; they determine many things, including physical features (eye color, curly or straight hair, height), but sometimes, they determine the likelihood of whether we’ll develop certain diseases, like cancer or diabetes, as well.
Genetic tests look at these genes to see whether there are any indicators that might increase your risk for cancer, like BRCA1 and BRCA2, or whether your blood clots too much or too little, like Factor V Leiden. They can even let you know whether you’re a carrier for something that may impact a pregnancy, like Cystic Fibrosis or Tay Sachs. Genetic tests can be very targeted and look for only one or two specific mutations, or they may be comprehensive and look for a million changes.
Not all genes are created equal when it comes to determining your risk for disease. One gene may increase your risk by 5 percent, while another may increase it by 50 percent. Needless to say, making sure that you’re getting the right genetic test and understanding the implications of the results can be very complicated.
At-home Genetic Tests Pros & Cons
Let’s walk through the pros and cons of at-home genetic testing.
- DTC genetic test kits are relatively affordable. They are paid for up-front and do not require insurance approval. Many companies offer their kits for less than $400.
- They provide information on ancestry. Some companies even break down the information to include percentages of ethnic, geographic and even Neanderthal DNA.
- You can obtain this information privately, without physician or insurance approval or knowledge. Your results can include information about predisposition to Alzheimer’s, or whether you are a carrier for some conditions such as Cystic Fibrosis.
- The information can inspire you to make lifestyle changes, like adopting a healthier diet or exercising more regularly.
- By ordering a genetic test on your own, you’re missing an opportunity to gain expert medical advice that can help you understand what your test results actually mean for your health, your future, and your family.
- Not all genetic testing is the same. To keep costs low, the at-home tests often only look for one or two of the most common gene mutations that signal hereditary disease risk. If you are only looking for one change, how can you be sure it’s right one? It’s important to understand that even if this test says you are not a carrier for anything, they are really saying that you’re not a carrier for the specific mutation(s) they looked for. You could still be a carrier for another mutation. There may also be multiple genes contributing to the risk for a disease, and you were tested for only one. (This is where consulting with a genetic counselor can be invaluable. He/she will do in-depth research into your family health history to determine which gene mutations you should be tested for.)
- It’s easy to over-estimate the role genetics plays in some hereditary diseases. But how much genetics contributes to a disease varies widely. The vast majority of the diseases the at-home tests look for are influenced more by lifestyle or environment than by genetics.
- These complicating factors can make it difficult for a consumer to understand what the results actually mean. When you use a DTC test, results are often delivered by email or on a website, and without explanation, they can be frightening. DTC test results likely don’t include how your risk compares to the general population, or give you a timeframe for when a disease you’re predisposed to may or may not occur. They rarely give advice on how to mitigate your risks to avoid getting the disease in question. Genetic testing—and its results—can have implications for your whole family. Any gene mutations that you carry can be passed down to your children or grandchildren. And it’s most likely that you inherited them from your mother or father, meaning your parents and your siblings may also carry them too! How do these results impact your family members? Do they want to know this information?
- Getting genetic results can be an emotional experience. You may feel a wide range of emotions including confusion, guilt and anger after receiving these results. DTC testing leaves you to deal with the impact of the results on your own.
The Bottom Line
DTC genetic testing can provide interesting information, and it can be fun to learn about your ancestry! But before you purchase an at-home genetic test kit, ask yourself a few questions. Is this test going to tell me the information I want? Which genes are analyzed, and what can I really learn about my health from the results? How will my family be affected? How will this company use my genetic information; will they sell it or share it with anyone else?
As a genetic counselor, I am a trained expert in genetic testing and aware of all the pros and cons that come with it. Genetic counselors can be found all over the country and in many different specialties, including cancer, prenatal, cardiology and neurology. We are here to help you navigate the process of genetic testing, to answer your questions, and to be sure you totally understand the results.
If you’re consider genetic testing, talk to your doctor or healthcare provider about whether an at-home test kit will provide useful information, and make sure they are able to help you interpret the results. It’s important to remember that DTC genetic testing is not a substitute for a medical consult. If you are interested in genetic testing, ask your doctor for a referral to a trained genetic counselor.
At SMH, we provide genetic consults related to cancer risks. If you are concerned about your risk for cancers, talk to your physician about your family history, or reach out to our Genetic Education and Counseling Program team at 941-917-2005. You can find out more about SMH’s genetic testing for hereditary cancer services at smh.com/genes.
Nicole Wood, MS, CGC, is the only licensed and board-certified genetic counselor serving Sarasota County and its surrounding communities. Specialty trained in oncology genetic counseling, Wood works closely with a multidisciplinary team at Sarasota Memorial Hospital to provide expertise for patients’ clinical care. She contributes regular blog posts on topics related to genetic testing, counseling and hereditary cancer syndromes.