23andMe (and You)
by Bailey Sasseville
Have you ever wondered if you have a deadly mutation lurking somewhere within your DNA? Now you might be able to find out. As genetic testing has become cheaper and cheaper, various companies have arisen to take advantage of the technology and satisfy people’s curiosity by providing mail-in genetic testing services. For $199, 23andMe will test your DNA for known variants associated with development of diseases such as breast cancer, Alzheimer’s and Parkinson’s and for carrier status of conditions such as cystic fibrosis and sickle cell anemia, in addition to giving you reports about ancestry, wellness and other topics. When it comes to finding out valuable information about your chances of developing a debilitating disease or your risk for passing it on to your future children, this can seem like a great deal. However, interpreting complex genetic information on your own can be difficult without a background in biology.
These reports are often lacking in detail and raise more questions than they answer. Imagine you have a family history of breast cancer and want to find out your risk of developing it as well. 23andMe offers tests of your BRCA1 and BRCA2 genes, which are known to increase your risk of developing certain cancers, particularly breast and ovarian. You send in your DNA sample and find you have tested negative for the three variants 23andMe tests for. But here’s the problem: there are over 1,000 variants in these two genes known to increase your cancer risk, so you barely have any more information than you started with and you might end up even more worried than you were before.
A positive test result can lead to questions, too. Maybe the report tells you that you have one of the three BRCA variants tested for and gives you an estimate of the likelihood of developing breast cancer with this variant. For example, a recent study found that 72 percent and 69 percent of women with BRCA1 and BRCA2 mutations respectively developed breast cancer by age 80. You are left to deal with the fallout from this information on your own, with just an emotionless computer screen blinking back at you. Without a medical background, it’s hard to put numbers like that into context, especially as they are heavily influenced by many factors like family history, lifestyle and other genes. You will likely be left wondering what these results really mean, what do to next and how these results could affect relatives who may also be at risk.
At times like these, people often turn to genetic counselors — health care professionals specialized in evaluating a person’s risk for inherited conditions and helping them fully understand the complex genetic information needed to make informed health decisions. Michele Clemens, a genetic counselor at Magee-Womens Hospital in Pittsburgh, said she sees many patients who are seeking clarification and further information after getting genetic testing from sites like 23andMe. They want to know what their risk for developing a disease really is when other factors are taken into account, how the results will affect their future and their children and relatives who may be at increased risk for the same disease, and what their options are for next steps. Often the process begins with confirmatory testing. “It’s important for patients to understand whether there actually truly is a mutation or gene change identified,” Clemens said, “or whether it’s something that is a variant that hasn’t been reported before or a variant that’s not considered to be significant.” Clemens described genetic counseling as an “education process,” as counselors explain and interpret test results and advise patients on how to make informed medical decisions, something 23andMe fails to do. In fact, the website itself recommends speaking to a genetic counselor or other medical professional if you have concerns or a family history of a condition.
Clemens believes that before getting genetic testing through online companies like 23andMe, people should speak to a genetic counselor. Even though information about genetics and genetic testing is constantly growing and becoming more available to the public, Clemens said, “I think we would consider genetic counselors to still be a better resource in terms of explaining to patients the appropriateness of a genetic test related to whatever their concern is.” To become a genetic counselor, a person must receive a bachelor’s degree and complete necessary prerequisite classes including genetics, biochemistry and statistics before applying to an accredited master’s program. These programs are exceptionally competitive, as each class only consists of an average of 8 to 10 students and are rigorous enough to ensure graduates have a thorough background in genetics, human physiology and counseling. Genetic counselors are extensively educated on available testing for different conditions and can help a patient decide what conditions to test for, which genes and variants to test and whether testing is even necessary.
In many cases, this can be an emotionally complex decision that warrants more careful thought than a few clicks of a computer mouse. People typically consider several scenarios: if they test positive for a variant causing increased risk of a condition, will they wish they hadn’t received testing in the first place? If they test negative, will they be comforted or worry they will still develop the condition anyways or have a variant that wasn’t tested for? For late-onset diseases with no cure such as Alzheimer’s, some people may decide they’d rather not have any knowledge of their genetic risk than knowing they have an increased risk. They believe they’d live more peacefully and fully without constantly wondering if symptoms are beginning to appear, especially since the disease is affected by so many other factors than a few genes. Some couples may want to know whether they carry copies of a disease-causing variant in order to make decisions about conceiving a child while some prefer to simply see what happens. Those who have already have children with a condition may prefer not to know if they’ve passed a harmful variant on, as it can cause unwarranted feelings of guilt and ultimately won’t provide any helpful information. There is no one right decision for any person, but talking to a genetic counselor can help a person consider and work through all the implications of genetic testing, many of which he or she might have never considered in the first place.
Many people don’t understand how complex the effects of genetics can be, believing that having a mutation associated with a disease means they will develop the disease. In reality, it’s much more complicated and affected by many factors, even ones we haven’t discovered yet. Epigenetics is the study of mechanisms that turn genes on and off, many of which are still not fully understood. This means that the everyday choices we make, what we eat, how much we exercise and where we live can have profound and unpredictable influences on everything from your future children’s susceptibility to asthma to the risk of developing schizophrenia.
Additionally, even if two people have the same disease-associated variant, one with a family history of the disease is more likely to develop the disease than one with no family history. Many diseases are also affected by multiple genes, some of which may be undiscovered. These are all complicating factors in disease progress that sites like 23andMe are unable to address, except by acknowledging that these factors exist without explaining the full implications in the way that a genetic counselor could.
So why are sites like 23andMe still so popular? “The marketing ability of these direct-to-consumer companies is very great and I think sometimes it’s just people’s curiosity,” said Clemens. The ease of ordering genetic testing and seeing the results all online is undeniably appealing. And many people don’t fully understand what sort of information their results can and can’t provide, so they don’t give much consideration to whether they actually want this knowledge or whether it will be helpful or detrimental. The price is pretty appealing, too — while the price of genetic testing through a genetic counselor varies considerably depending on insurance and the specific tests being done, Clemens said 23andMe is pretty inexpensive. Of course, if a person ends up going to a genetic counselor anyways for more information, that’s an extra $199 he or she didn’t need to spend in the first place. Additionally, some patients decide genetic testing isn’t even necessary after a genetic counselor examines their family history.
Overall, genetic counseling is just a better bet than online testing if you’re concerned about how your genes are affecting your health. As they are often embedded into health care teams, genetic counselors are an important part of your support system and help coordinate your care with other medical professionals. They are there to answer any questions you have, help you make informed decisions and help you cope with the results you get. They also contact your insurance companies and advocate for coverage of any genetic testing you may need. A genetic counselor is a compassionate, supportive professional, while services like 23andMe are faceless websites. “We’re here to explain and to educate,” Clemens said. “I would hope that even if I have to give someone bad news or news that they’re not expecting that it’s being delivered in a way that they can understand it and that is compassionate and that I'm helping them through whatever process they’re going through.”