Hypoxanthine-Guanine Phosphoribosyltransferase Deficiency

A DEFICIENCY in the enzyme hypoxanthineguanine phosphoribosyltransferase (HPRT) is associated with two clinical syndromes. Enzyme activity is virtually absent in the Lesch-Nyhan syndrome.1 This disease is characterized by overproduction of uric acid and a Central-nervous-system disorder that consists of mental retardation, spasticity, choreoathetosis, and a compulsive form of self-mutilation.2 HPRT activity is partially deficient in the second syndrome, which is characterized by overproduction of uric acid and a severe form of gout.3 Patients with this disease do not suffer from the neurologic abnormalities that are found in the Lesch-Nyhan syndrome. The enzyme deficiency in both disorders is X-linked.Since its . . .