Lesch-Nyhan syndrome is a rare hereditary disease that can cause intellectual disability. Lesch-Nyhan syndrome results from a deficiency of hypoxanthine-guanine phosphoribosyl transferase, an enzyme found in all body cells. This enzyme is present in particularly high levels in the basal ganglia of the brain. The basal ganglia help control body movements. In addition to intellectual disability, symptoms of Lesch-Nyhan syndrome include uncontrollable movements and a tendency to inflict self-injury.
Patients inherit the syndrome through a defective gene on the X chromosome, one of the two chromosomes that determine sex. Males have one X chromosome and one Y chromosome, and females have two X chromosomes. A male who inherits the defective gene will develop the disease. But a female develops the disease only when the defective gene occurs on both X chromosomes. A female who carries the defective gene can transmit the defect to her children.
Lesch-Nyhan syndrome cannot be cured or effectively treated. The disease was first described in 1964 by William Nyhan, an American professor of medicine, and one of his students, Michael Lesch.
