The anti-MDA5 antibody is detected at high frequencies among patients with DM in Asia (15.8% [26/165 cases] in Japan and 36.6% [53/145 cases] in China)7 and South America (16% [21/131 cases] in Brazil)8 and at low frequency (2.8%, 21/748 cases) in a cohort of patients with DM in a combined European cohort in which 87.4% of enrolled cases were Caucasian9. This evidence concerns the gene IFIH1 and dermatomyositis.