PI4KAP1 was found to have a higher expression in CD4+ T cells of HLA-DRB1*03-positive patients with myositis, and TRGC2, CTSW, HPCAL4, ZNF683, and GOLGA8B were found to have a higher expression in CD4+ T cells of HLA-DRB1*03-negative patients with myositis. This evidence concerns the gene CD4 and myositis disease.