At present, a valid hypothesis is that the immunopathogenesis of DH starts from hidden coeliac disease in the gut with a TG2, and possibly also a TG3, autoantibody response and evolves into an immune complex deposition of high avidity IgA TG3 antibodies together with the TG3 enzyme in the papillary dermis [48]. This evidence concerns the gene CD79A and celiac disease.