In a large population of more than 7000 normal blood donors studied for pemphigus and pemphigoid autoantibodies, we previously showed that the cumulative prevalence of these autoantibodies was 0.9%, with bullous pemphigoid (BP)-associated anti-BP180-NC16A IgG being most prevalent (0.5%) [2]. The gene discussed is COL17A1; the disease is bullous pemphigoid.