Direct-To-Consumer Genetic Testing for Celiac Disease

Can You Learn Whether You Have the Celiac Gene Through 23andMe?

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

Question: Can I find out whether I carry the gene for celiac disease through a genetic testing service such as 23andMe.com?

Answer: Right now, 23andMe.com does screen for the genes thought to predispose you to celiac disease, but due to U.S. Food and Drug Administration concerns about direct-to-consumer genetic testing, the company no longer provides these results to consumers.

It is possible to take your raw data from 23andMe (or from another genetic testing service, such as Ancestry.com) and run them through an online genetic calculator that will do some interpretation for you.

However, this won't provide you with the answer you're seeking on whether you carry the so-called "celiac gene," either — and frankly, the information these calculators do provide can be very confusing.

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

I've heard from several readers who have asked if direct-to-consumer genome-sequencing companies such as 23andMe.com and Ancestry.com test for the celiac gene. Well, they do ... sort of.

In case you're not familiar with 23andMe, it's a start-up company that will provide you with raw data on the genes you carry. 23andMe used to also provide some interpretation of these results, but in late 2013 the U.S. Food and Drug Administration cracked down on the company for doing so, saying its health reports (including the information it provided on the celiac gene) were unproven.

Therefore, 23andMe stopped providing these health reports, although the company does still provide the raw data.

As I said above, it is possible to take this raw genetic data and run it through an online genetic calculator. But even this won't provide you with an easy yes-or-no answer from these results on the question of whether you have the celiac gene — or more specifically, which HLA-DQ gene you carry.

Finally, there's conflicting information in the various genetic research databases available online about which specific pieces of genetic code are most important to your celiac risk.

So while these tests are quite interesting to do to learn your ancestry (they even provide your percentage of Neanderthal genes!), they're not hugely informative when it comes to celiac disease.

The Bottom Line

You should 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. 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.

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