Childhood dermatomyositis is a multisystem autoimmune disease characterized by acute and chronic inflammatory infiltrate and vasculitis seen primarily in skin and muscle. The disease occurs in genetically susceptible individuals with a yet undescribed environmental trigger. Genetic associations in this disease demonstrate disease susceptibility as well as chronicity and severity and likely play a role in disease pathogenesis. The majority of the associations to date have been seen with the HLA alleles, with additional immune responsive and influential genes being increasingly investigated.