In our cohort of JDM patients, all patients with anit-NXP-2 or anti-TIF1γ autoantibodies had prominent capillary C5b-9 deposition, while patients with anti-Mi-2 and anti-MDA5 autoantibodies had minimal to no capillary C5b-9 deposition. The gene discussed is IFIH1; the disease is juvenile dermatomyositis.