A number of extremely rare genetic diseases, occurring in 1–80 per million live births, that affect the metabolism of individual amino acids; if untreated, many result in mental retardation. Screening for those conditions that can be treated is carried out in most countries shortly after birth. Treatment is generally by feeding specially formulated diets providing minimal amounts of the amino acid involved. See also argininaemia; argininosuccinic aciduria; citrullinaemia; cystinuria; cystathioninuria; Hartnup disease; homocystinuria; hyperammonaemia; maple syrup urine disease; phenylketonuria.
Subjects: Medicine and Health.