Lesch-Nyhan syndrome

Lesch-Nyhan syndrome is a rare genetic disorder caused by a deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase, resulting from mutations in the HPRT1 gene located on the X chromosome, which makes the condition X-linked recessive and means it predominantly affects males. The enzyme deficiency causes both increased production and decreased recycling of purines, leading to a marked buildup of uric acid in the body that produces gout-like joint problems and kidney damage. The disorder also causes significant neurological dysfunction, including poor muscle control, and is especially notable for severe behavioral disturbances, including compulsive self-injurious behavior such as biting, that typically begin around age three. The condition was first described in 1964 by Michael Lesch, then a medical student, and pediatrician William Nyhan at Johns Hopkins School of Medicine, and its underlying metabolic cause was identified within three years by J. Edwin Seegmiller and colleagues at the National Institutes of Health. It is estimated to occur in roughly three of every 380,000 live births.