It should be borne in mind, however, because of its intracellular location, that GAD65 as a pathogenic autoimmune target might be doubtful; GAD65-Abs could in fact be harmless bystander immunoglobulins, while other, genuinely pathogenic, but unknown, autoantibodies could be present in the same individual, causing an autoimmune disease (8, 9). This evidence concerns the gene GAD2 and autoimmune disease.