SCO2 protein is a member of the SCO1/2 family. SCO1 and SCO2 proteins are found on the inner membrane of the mitochondria and takes a vital part copper insertion or transport to the active site of cytochrome c oxidase （COX）. Flaws in SCO2 are the reason for deadly infantile cardioencephalomyopathy with cytochrome c oxidase deficiency （FIC） which is characterized by hypertrophic cardiomyopathy， lactic acidosis， and gliosis. Heart and skeletal muscle display declines in cytochrome c oxidase （COX） activity， while liver and fibroblasts show mild COX deficiencies.
