In humans, the gene COX7A2 is associated with Fatal Infantile Cardioencephalomyopathy due to Cytochrome C Oxidase Deficiency (ORPHA1561), a very rare mitochondrial disease, clinically recognized by cardioencephalomyopathy resulting in death in infancy. This evidence concerns the gene COX7A2 and hyperinsulinemic hypoglycemia, familial, 4.