The two “celiac disease genes” – HLA-DQ2 and HLA-DQ8 (HLA stands for “human leukocyte antigen”) – appear in about 35% to 40% of the U.S. population, most commonly among those with European ancestors. But only about 1% to 4% of those with the “celiac disease genes” will ever be diagnosed with celiac disease, which affects about one in 100 people overall.
But while medical experts don’t recommend going gluten-free on the basis of the celiac gene test alone, they do recommend regular celiac blood tests for family members of those with the disease. So if you had the gene test because a relative was diagnosed – and if your gene test was positive – you’re now in a high-risk group, and you’ll need to be monitored.
If you had the gene test because you have symptoms of celiac disease but negative results on other celiac screening tests, you and your doctor might decide you should stop eating gluten for a trial period to see if your symptoms clear up while you’re gluten-free.
But if you do decide to stop eating gluten (and some people feel better once they give up gluten even if they’re not diagnosed celiac), just make sure you’ve finished all medical testing for celiac disease first. If you’re already gluten-free, you risk false negatives on the tests that diagnose the condition. The celiac blood test panel looks for specific antibodies to gluten in the bloodstream, while the endoscopy looks for gluten-related damage in the small intestine. Both issues that can reverse, often quickly, if you stop eating gluten.
Genetic Testing. Consumer Information Sheet. The University of Chicago Celiac Disease Center. Accessed: June 7, 2010.