Etiology of celiac disease

Celiac disease occurs in genetically susceptible individuals. Approximately 97% of patients have the DQ2 and/or the DQ8 markers of HLA haplotypes, whereas only 40% of the general population is positive for these markers. First and second degree relatives have a high probability of having celiac disease as well (4 to 12% of first degree relatives have changes on duodenal biopsy). Although there appears to be a genetic predisposition for celiac disease, many individuals do not have any clinical problems until long after they have first been exposed to gluten as an infant. Triggering factors present in the environment are thought to cause celiac disease in genetically susceptible individuals. For instance, viruses may be one trigger. The common virus adenovirus 12 is a known triggering factor, possibly because it shares a sequence of amino acids with gluten.