Some case series have reported CADM frequencies of approximately 40% in anti-MDA5 antibody-positive DM adult patients; in the juvenile cohort, it was reported that anti-MDA5 antibody-positive patients had a lower prevalence of severe muscle weakness than anti-MDA5 antibody-negative JDM patients [20]. Here, IFIH1 is linked to clinically amyopathic dermatomyositis.