Some autoantibodies, in particular, myositis-specific autoantibodies such as anti-aminoacyl tRNA-synthetase (ARS) and anti-melanoma differentiation-associated gene 5 (MDA-5) antibodies, were reported to be associated with the unique clinical features of polymyositis/dermatomyositis (PM/DM). The gene discussed is IFIH1; the disease is polymyositis.