Patients with anti-Mi2 autoantibodies present with a classic JDM characterised64 with proximal muscle weakness and skin rash, while patients with anti-MDA5 autoantibodies are more likely to have associated ILD and have milder muscle disease.65 Unfortunately, despite accessing samples from the large Juvenile Dermatomyositis Cohort and Biobank study (JDCBS), we were still underpowered to stratify our data based on MSA subtype. Here, IFIH1 is linked to dermatomyositis.