A molybdenum cofactor deficiency that has material basis in homozygous mutation in the GPHN gene on chromosome 14q23. The disease is MONDO_0014212 (sulfite oxidase deficiency due to molybdenum cofactor deficiency type C). Also known as: MOCOD type C, MOCODC, combined deficiency of sulfite oxidase, xanthine dehydrogenase and aldehyde oxidase type C, molybdenum cofactor deficiency C, molybdenum cofactor deficiency complementation group C, molybdenum cofactor deficiency, complementation group type C.