A photo of the the 23andMe at-home genetic test kit.
Photo: 23andMe

Last month, 23andMe—a leader of at-home genetic testing—introduced the first over-the-counter breast cancer screen. Soon after, another company called Color released an at-home genetic test for heart disease.

These products differ in important ways: Color’s heart disease test requires a doctor’s prescription, and 23andMe’s breast cancer screen does not. But both have added fuel to an ongoing debate among doctors, regulators, and consumers about at-home genetic testing.

More on At-Home Health Tests

Fans of the tests see them as a convenient, inexpensive way to give consumers direct access to vital information about their health. For just a few hundred dollars, you receive a kit at home, spit into a vial, send it back to the company, then check online a few weeks later for results.

“Genetic information is a powerful way to motivate people to take more interest in and ownership of their own health,” says Kathy Hibbs, chief legal and regulatory officer at 23andMe. “And direct-to-consumer tests help us get that information to people who might not be able to access it otherwise, either because of the way insurance works or because they don’t see a doctor in the first place.”

But critics say that issues raised by over-the-counter genetic tests are more complex than those raised by other at-home tests, such as using a home blood pressure monitor.

They worry that such tests can create a false sense of security—or needless fear—among consumers who misunderstand what the results mean or who get inaccurate results to begin with.

They also worry about privacy: Medical information obtained online often isn’t subject to the same legal protections as information taken in a hospital or doctor’s office. And the comprehensive nature of genetic information—combined with the reality that the results affect not just people who order the test but also their families—magnifies those concerns.

The Food and Drug Administration has cautioned consumers about over-the-counter genetic tests, warning that while they may provide some useful information, they are not meant to be a substitute for a comprehensive assessment from medical professionals.

But the agency has also cleared the path for more such tests to enter the marketplace. For example, carrier tests—which tell you your risk of passing certain conditions, such as cystic fibrosis, down to your offspring—no longer need to be approved by the FDA before they are sold.

And thanks to advances in the field, home genetic testing is becoming more common and more affordable. “The speed of gene sequencing technology has gone way up, and the cost has come way down,” says Michael Watson, president of the American College of Medical Genetics. “When you combine those developments with the power of the internet, it becomes easier than ever to get this information into just about anyone’s hands.”

Here is what you need to know about genetic testing, and what to keep in mind if you’re considering it.

DNA Is Not Destiny

Erica Ramos, president of the National Society of Genetic Counselors, suggests imagining your disease risk as marbles in jar, where a full jar means you develop the condition in question.

Take mental illness: If you have a family history of schizophrenia, you start out with some marbles in your jar. Things like not getting enough sleep and using drugs or alcohol add more marbles. But eating right and exercising can take marbles out. “It’s a constant back-and-forth between genes and environment,” Ramos says. “You really need to understand both sides to know your true risk.”

In fact, most diseases, including the ones such as cancer, Alzheimer’s, and heart disease that genetic testing companies screen for, are not primarily genetic. According to Watson, just 5 percent of all cases of such conditions are inherited. “Most people develop the more garden-variety forms of these diseases,” he says. “That means versions that are caused by a mix of factors, including their underlying health, the environment they live in, and their broader family history.”

“Family history” can be much more complicated than having a few scattered gene variants. For example, you may have inherited a genetic mutation that increases your odds of getting breast cancer. But you may also have traits that offset that risk, such as other genes that compensate for the dysfunctional one. Scientists are still figuring out how all of those factors interact. In the meantime, doctors look at actual health outcomes within your family tree for clues about how any one of your genes might actually behave. 

Your Doctor's Orders

The most accurate way to get information about your genetic health risks is still through tests that a doctor (often an oncologist or OB-GYN) orders for you. These tests tend to be far more comprehensive than those that can be purchased over the counter because they usually sequence entire genes and look for many variants that have been linked to the disease in question. 

When should you consider these tests? There are three broad instances when doctors may order genetic testing: If you are pregnant or trying to become pregnant (these tests are called carrier screens); if you have a family history of a certain disease such as breast or ovarian cancer (meaning multiple family members on the same side of the family have developed the disease, often early in life); and if you have symptoms of a disease like Alzheimer’s that sometimes has a genetic component.

What will they tell you? Carrier screens will tell you your risk of passing scores of diseases, such as Cystic Fibrosis and sickle cell disease, on to your offspring. These are diseases you don’t have yourself but that you may carry one copy of a contributing gene variant for. Other doctor-ordered genetic tests can help confirm tricky diagnoses (like Alzheimer’s), or—when combined with other information—give you a better sense of your risk for a given disease.

How much do they cost? These tests can run into the thousands. But if your doctor is ordering them, they are most likely covered by insurance, in which case they might cost as little as an office-visit co-pay.

When to Seek Genetic Counseling

It’s often best to talk with a genetic counselor before you get tested. They are licensed healthcare professionals (often covered by insurance) who can help you decide whether testing makes sense for you and, if so, which ones will be most useful. If you opt for testing, they can also help interpret results, decide on next steps, and communicate with family members about what the information means for them.

In most cases, your doctor will refer you to a genetic counselor, Ramos says. To help with your search, the National Society of Genetic Counselors recommends findageneticcounselor.com.

How to Protect Your Privacy

If you’re concerned about privacy, our experts advise you to delete any account containing your genetic information once you download your test results.

Here’s why: The Health Insurance Portability and Accountability Act (the privacy law known as HIPAA) protects only information handled by specific entities such as doctors, hospitals, and insurance companies. Genetic tests administered by a healthcare provider fall under this law. Those that you purchase directly (without a prescription) do not. That means that depending on the rules of a given company, your genetic information can be freely shared—with scientists, insurance companies, or, theoretically, anyone who’s interested.

The Genetic Information Nondiscrimination Act prohibits employers or health insurance companies from using a person’s genetic information to make employment or health insurance decisions. But that law does not apply to long-term-care insurance, disability insurance, or life insurance. So your genetic information—a risk of early-onset Alzheimer’s, say, or breast cancer, for example—can potentially be used against you when you’re seeking these types of insurance.

The good news is that genetic testing companies are bound to whatever promises they make in their own policies. 23andMe has an opt-in rule that prohibits them from selling your genetic information unless you give express consent for specific research projects when you sign up for its services.

Consumer Reports’ privacy experts think this is a best practice that other genetic testing companies should adopt. “We think consumers are better served by getting specific notice and choice regarding which research projects their genetic information is used for,” says Katherine McInnis, an attorney at Consumers Union, the advocacy division of Consumer Reports.

23andMe

So far, 23andMe is the only company to secure FDA authorization for its over-the-counter genetic health risk test. This means they’ve proved to the agency that their screens are accurate and easy for consumers to understand. But be warned: “FDA approved” does not necessarily mean “clinically useful.” 23andMe relies on much simpler technology than tests you’d get at the doctor’s office. As a result, it doesn’t test all the variants in a given gene, nor does it test all the genes linked to a given disease. 

When should you consider this test? Many medical experts, including those at Consumer Reports, say the 23andMe screen is really good only for curiosity’s sake. If you have a known risk for one of these diseases (such as a family history or actual symptoms yourself), you should see a doctor.

What will it tell you? At most, 23andMe tests will tell you that you carry a version of one or two genes that have been linked to an elevated risk for a given disease. It won’t tell you whether you carry all (or none) of the variants linked to that disease, and it won’t factor other information, such as family history, into its final analysis. That means the results won’t tell you much about your chances of actually developing the disease yourself. 

How much does it cost? 23andMe does not accept insurance. Its full health screen (which includes tests for eleven conditions, including Alzheimer’s, Parkinson’s, and celiac diseases, and–most recently–breast cancer) costs $199.

Other Options

There is a rapidly growing list of other genetic testing options that can be bought online or even at walk-in drugstores. The best of them are as comprehensive as the ones your doctor might order, and are available only with a prescription. 

When should you consider these tests? They are relatively affordable prescription tests that you can buy online, which might make sense if you are uninsured or if you don’t know your family history and want to assess your genetic risk for something like breast cancer or cardiovascular disease. (Insurance companies may refuse to cover such genetic tests without a family history.)

What will they tell you? Many of the prescription tests you buy online will tell you about as much about your genetic health risk as the ones ordered by your doctor. In some cases, the results of these tests are delivered by an actual doctor or genetic counselor, so you may also get some information about what to do next.

How much do they cost? It depends on the company and the test. Color (the company that just released a cardiac test) sells a BRCA test that sequences the entire gene for $99; the company’s cardiac panel, which tests for hundreds of versions of 30 genes linked to a number of heart conditions, costs $250. Because they require a prescription, Color’s tests (and others like theirs) are often covered by insurance.


A Guide To 23andMe Home Genetic Tests

23andMe is still the only company where you can buy genetic tests without a doctor’s prescription. Here’s a quick rundown of its tests:

Carrier Screens

The 23andMe carrier screen is as accurate as the one ordered by your doctor, but it’s not as comprehensive. It includes tests for gene variants associated with cystic fibrosis, sickle cell disease, Tay-Sachs, and some others. But several conditions that doctors recommend having carrier screens for, such as spinal muscular atrophy, are missing from its test. What’s more, your doctor will need to confirm any positive test results with a test he or she orders.

Breast Cancer

The company’s breast cancer test detects three BRCA mutations. Women with at least one have a 45 percent to 85 percent chance of developing breast cancer by age 70 (compared with a 12 percent chance in the general population). But the mutations themselves are rare: Just 2 out of 100 Ashkenazi Jewish women and 1 out of 1,000 women in the rest of the population have them. And testing negative does not mean you are in the clear. There are more than 1,000 other BRCA mutations—and many more nongenetic factors—that contribute to your breast cancer risk. If you have an Ashkenazi Jewish background, the test might be useful. But most medical experts say it’s better to have a full BRCA screening test done in consultation with your doctor or genetic counselor.

Alzheimer’s Disease

This test detects a variant of the ApoE4 gene that can raise your risk of developing late-onset Alzheimer’s to nearly 80 percent. Only people with two mutations in both copies of the gene face that 80 percent risk. For everyone else, the meaning of the results are much more variable. What’s more, very few cases of late-onset Alzheimer’s—just 2 to 3 percent, according to the American College of Medical Genetics and Genomics (ACMG)—are hereditary to begin with. That means most people who develop Alzheimer’s don’t have a the ApoE4 variant that 23andMe tests for, and many people who do have the variant don’t go on to develop the disease. Early onset Alzheimer’s (the kind that comes in your 50s or early 60s) is a different story: There are several genes that are strongly associated with this disease. But 23andMe doesn’t test for these genes. And doctors will only if you have a strong family history or if you are symptomatic yourself.

Parkinson’s Disease

This test checks for a gene variant believed to triple the risk of Parkinson’s. But that’s not as dramatic as it sounds. A positive result means you have a 1 percent risk of developing Parkinson’s, compared with a 0.3 percent risk in the wider population. There are more comprehensive genetic tests for Parkinson’s. But a doctor is likely to order one only if you have a strong family history of the disease or if you develop symptoms at young age. As with cancer and Alzheimer’s, only a small portion of Parkinson’s cases are believed to be genetic to begin with.

Other Rare Diseases

23andMe also offers genetic risk tests for eight other diseases, including celiac disease, hemochromatosis, and several blood disorders. The ACMG recommends against most of these tests as well because they are not very clinically useful. For example, a positive result in the celiac test generally means you have a 3 percent risk of developing the condition (compared with 1 percent in the wider population). “Removing all wheat from your diet based on something you have a 3 percent chance of getting is not the best idea,” Ramos says. “It’s a difficult thing to do, and it comes with at least some risk of nutritional deficiency.”