What Is the Gene HLA-DQ7, and Is It Related to Celiac Disease?

strands of dna
Can the gene HLA-DQ7 predispose you to gluten issues?. Endai Huedl / Getty Images

The gene HLA-DQ7 is not considered one of the main genes that can predispose you to celiac disease. But there is some evidence that it might play a role in the condition, and possibly in non-celiac gluten sensitivity.

Celiac disease is a genetically based condition, which means you need to have the "right" genes to develop it. Researchers have found that your HLA-DQ genes seem to play a primary role in villous atrophy—the characteristic intestinal damage found in celiac disease.

HLA-DQ Genes and Celiac Disease

Bear with me: this gets complicated and confusing.

Everyone inherits two HLA-DQ genes from their parents—you get one from your mother and one from your father. 

There are many different forms of HLA-DQ genes, including HLA-DQ7, HLA-DQ2, HLA-DQ8, HLA-DQ9 and HLA-DQ1. You may inherit two different HLA-DQ genes (the most common scenario), or a double dose of one particular HLA-DQ gene (a much less common scenario).

Out of all those different forms of HLA-DQ genes, there are two that are so-called "celiac disease genes:" HLA-DQ2 and the less-common HLA-DQ8. Most people who develop celiac disease have HLA-DQ2, while a much smaller percentage have HLA-DQ8. Those two genes seem to account for about 96% of everyone diagnosed with celiac disease.

How HLA-DQ7 Fits In

There are some people who don't carry HLA-DQ2 or HLA-DQ8 and who still develop celiac disease.

At least one study has found that about half of these people (in other words, about 2% of all people with celiac disease) actually carry HLA-DQ7.

This shows HLA-DQ7 may be a gene that can predispose some people to the condition.

However, this view hasn't been backed up in other studies, and more research is needed to determine if HLA-DQ7—which is very similar to HLA-DQ8—indeed can lead to celiac disease, even if you don't have one of those main "celiac disease genes." At this time, most physicians don't consider HLA-DQ7 to be a celiac disease gene.

It's also possible that HLA-DQ7 plays some role in non-celiac gluten sensitivity, a condition considered to be distinct from celiac disease (even though gluten sensitivity symptoms are almost identical to celiac disease symptoms).

Dr. Kenneth Fine, who developed the gluten sensitivity testing technique used at Enterolab (a direct-to-consumer service), has collected HLA-DQ gene data on many Enterolab patients. He has concluded, based on his own unpublished research, that HLA-DQ7 predisposes you to gluten sensitivity. However, mainstream medicine generally discounts this research because it hasn't been published and vetted.

It's all but certain that there are many more genes involved in the development of celiac disease, but researchers have yet to identify them all. Research into gluten sensitivity is just beginning, and scientists haven't determined whether it's a condition that's strongly genetically based.

Sources:

Sacchetti L. et al. Discrimination between Celiac and Other Gastrointestinal Disorders in Childhood by Rapid Human Lymphocyte Antigen Typing. Clinical Chemistry. Aug. 1998, Vol. 44, No. 8, p. 1755-1757.

University of Maryland Center for Celiac Research fact sheet. Celiac Disease Frequently Asked Questions. 

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