Anti-MDA5 antibodies (also referred to as anti-CADM-140 antibodies) were first identified in the serum from patients with clinically amyopathic DM (CADM) by immunoprecipitation (IP) assays and shown to recognize a cytoplasmic 140-kDa protein [3]. The gene discussed is IFIH1; the disease is clinically amyopathic dermatomyositis.