Strong evidence shows that in order to develop celiac disease, a person must have one or both of two genes known as HLA-DQ2 and HLA-DQ8. The major environmental factor, of course, is gluten ingestion. Gluten proteins interact with the celiac disease genes to trigger an abnormal immune response that damages the lining of the small intestine.
More than 97% of patients with celiac disease have at least one of the two genes. Most patients (more than 90%) carry the DQ2 gene. Fewer than 10% carry the DQ8 gene. As more and more studies are conducted, researchers will likely discover additional genes that predispose an individual to celiac disease. However, many professionals will argue that having these so-called “celiac disease genes” does not mean you’re guaranteed to have celiac disease. Having the genes only means you have a risk of someday developing celiac disease. On the other hand, if you don’t have these genes, your odds of developing celiac disease are slim to none.