Direct-To-Consumer Genetic Testing for Celiac Disease

Will 23andMe.com testing tell you whether you have the celiac gene?

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Direct-to-consumer celiac genetic testing. Liam Norris/Getty Images

You can find out whether you carry one of the genes for celiac disease through 23andMe.com, which tests for those so-called "celiac disease genes" as part of its overall genetic profiling service. The U.S. Food and Drug Administration has approved the celiac gene test, along with several other tests for genes that influence your risk of certain diseases.

However, you should be aware that these test results from the direct-to-consumer company may not tell you much about whether you'll ever actually develop celiac disease.

That's because lots of people carry one of the genes, but few people with the genes actually develop celiac disease.

Some explanation is in order.

Why Your Genes Matter for Celiac Disease

First, the background: Celiac disease is a genetic condition, meaning that doctors believe you cannot develop it unless you carry the genes that predispose you to it. There are two main genes for celiac disease, known as HLA-DQ2 and HLA-DQ8. Also, having certain subsets of the HLA-DQ2 gene can increase or decrease your risk.

Of course, having the gene doesn't necessarily mean you'll develop the condition. Up to one-third of the population carries one or both of the genes for celiac disease, but only less than 1% will actually develop the disease. So other factors clearly are in play... and genetic testing won't clue you in on those other factors, many of which we haven't even identified.

Still, some people find the genetic information useful to see if celiac is even a possibility—for example, if they suffer from multiple symptoms that could signal celiac disease but celiac blood tests or even an endoscopy haven't provided clear answers.

It's also possible to use the genetic test to help determine your risk for celiac disease if you're currently gluten-free, since the blood tests for celiac don't work if you're not eating gluten. However, not all doctors agree on the utility of this test in practice.

Available Celiac Genetic Testing Options

Most people who get genetic testing for celiac disease are tested through their doctors' offices.

The test can be expensive (usually in the range of several hundred dollars, although I've seen price tags exceeding $500), and it's far more likely to be covered by your health insurance if your doctor orders it.

There are direct-to-consumer genetic testing options for celiac (and for other conditions) that don't require a doctor's orders. However, you need to keep in mind that these tests may or may not give you all the information you want, and some of them may be difficult to interpret.

A trained medical professional—especially a genetic counselor—can provide valuable perspective in interpreting the results, which is another reason to consider going through your doctor. 

23andMe Will Provide Information... But It May Not Be Useful

23andMe.com, which uses a sample of your saliva to isolate your DNA, analyzes your genes for ancestry, specific traits (curly vs. straight hair, for example), and for genetic relatives. The company also is moving into testing for genetic predisposition to certain conditions that are clearly genetically linked, including celiac disease.

Other genetic tests approved by the FDA include: Alzheimer's disease, Parkinson's disease, hereditary hemocromatosis (a disease where you have too much iron in your body), and hereditary thrombophilia, a blood clotting disorder.

In approving these tests, the FDA found them to be safe and effective (the legal standard for approval), but warned that genetic information is just one piece of the puzzle. Anyone using 23andMe.com to determine their genetic risk for celiac disease or any other condition should consult with their physician to discuss their results.

The Bottom Line

It's possible to get genetic testing for celiac disease through 23andMe.com as part of the company's overall testing. As part of the service, you'll learn if you carry the genes for celiac disease. You'll also see which parts of the world your ancestors came from, and get information on several thousand genetic relatives you almost certainly didn't know you had.

However, even if you do have the genes, that won't tell you if you actually have celiac disease or if you'll develop it in the future.

Meanwhile, if celiac disease runs in your family, you may be able to obtain celiac disease genetic testing through your physician; if a doctor orders the test, there are several labs available to do it, and insurance may cover it.

Either way, you should talk to your doctor about the testing. It might also be helpful to speak with a genetic counselor once you have your results in hand, as such a counselor can help you to understand your results and evaluate your risks.

Source:

U.S. Food and Drug Administration press release. "FDA allows marketing of first direct-to-consumer tests that provide genetic risk information for certain conditions." April 6, 2017.

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