Lesch-Nyhan Syndrome is a genetic condition characterized by an inability to produce an enzyme known as hypoxanthine-guanine phosphoribosyltransferasa (HGPT). This condition is X-linked, appearing only in boys, although women who carry the condition may experience some health problems. Like many other conditions which are genetic in nature, Lesch-Nyhan Syndrome is not curable, although the symptoms can be managed to make the patient more comfortable.
The HGPT enzyme is responsible for catalyzing a reaction which breaks down uric acid in the body. The lack of this enzyme creates a buildup of uric acid, leading to neurological problems, joint pain, and kidney problems. The condition begins to manifest at birth, with patients experiencing developmental delays and physical handicaps. One of the most distinctive features of Lesch-Nyhan Syndrome is that it causes involuntary muscle spasms and reactions accompanied with self mutilation such as biting, chewing, and scratching.
This condition was first described in 1964 by doctors Michael Lesch and William Nyhan. The affected gene has been identified as the HPRT gene. Boys can develop Lesch-Nyhan Syndrome when their mothers are carriers, or through spontaneous mutation. As with other X-linked traits in boys, if a mother is a carrier, the child has a 50% chance of inheriting the condition, because his mother may or may not pass down the affected X chromosome. In order for a woman to have Lesch-Nyhan Syndrome, her mother would need to be a carrier and her father would need to have Lesch-Nyhan Syndrome; while this is technically possible, it would be quite unusual.
Treatment for Lesch-Nyhan Syndrome is focused on patient care, since the condition is not curable. Drugs can be used to reduce the buildup of uric acid, and to help manage behavioral problems associated with the condition. Most patients require supportive equipment such as wheelchairs as they grow up, and because the condition is accompanied by physical deterioration, the life expectancy for patients with Lesch-Nyhan Syndrome is typically lower than that of healthy individuals.
Some carriers of Lesch-Nyhan Syndrome could develop gout later in life, along with other conditions associated with retention of uric acid, although their problems will be much less severe than those of their sons. When a child is diagnosed with a genetic condition, parents are usually encouraged to be tested to see if they carry it, both to determine whether the child's condition is the result of a mutation, and to see whether or not there is a risk for future children to have the condition. With the assistance of genetic testing and in vitro fertilization, parents can also choose to selectively implant embryos, should they decide to have children in the future.