SOD2 (superoxide dismutase 2) is a member of the iron/manganese superoxide dismutase family. SOD2 binds to the superoxide byproducts of the mitochondrial electron transport chain and converts them to hydrogen peroxide and diatomic oxygen. Failure of SOD2 to remove the superoxide byproducts leads to an increase in mitochondrial reactive oxygen species resulting in biochemical aberrations with features reminiscent of mitochondrial myopathy, Friedreich ataxia, and HMGCL deficiency. Mutations in SOD2 have been associated with idiopathic cardiomyopathy (IDC), premature aging, sporadic motor neuron disease, and cancer.