Lesch-Nyhan syndrome (LNS) is a very rare genetic disorder (1 in 380,000 individuals) caused by the excess production and accumulation of uric acid–the waste product of normal physiochemical processes that is found in blood and urine. The overproduction of uric acid may cause gouty arthritis, kidney stones, or bladder stones. In addition, it may cause problems in the nervous system and behavioral disturbances. People suffering from this problem show involuntary muscle movements such as jerking, flexing and flailing. Those with LNS cannot walk and are often wheelchair-bound. In addition, self-injury and head banging are some of the most common and unique behavioral problems found in people with LNS.
Two scientists, Michael Lesch and William Nyhan, gave the first detailed clinical report of Lesch-Nyhan syndrome in 1964. However, the enzyme associated with LNS, enzyme hypoxanthine-guanine phosphoribosyl transferase (HPRT), was first discovered by Seegmiller and colleagues in 1967. The gene involved in encoding the human enzyme was cloned and then sequenced by Friedmann et. al., in 1985.
Cause of Lesch-Nyhan Syndrome
The disease is caused by mutations in the HPRT1 gene, which leads to severe deficiency of the enzyme hypoxanthine phosphoribosyltransferase 1. This enzyme plays a vital role in recycling purines, one of the building blocks of DNA and its chemical cousin RNA. Due to a lack of the enzyme hypoxanthine phosphoribosyltransferase 1, purines break down and cause high levels of uric acid inside the body.
How is Lesch-Nyhan Syndrome inherited?
The disease is inherited through an X-linked recessive pattern. The gene that is responsible for this disorder is located on the X chromosome. In males, since only one X chromosome is present, one altered copy of the gene in each individual cell is enough to cause the condition. In females, two X chromosomes are present, so a mutation would be required on both the copies of the gene to cause the syndrome. That’s the reason why LNS is more prevalent in men than women. One of the major characteristics of X-linked inheritance is that fathers cannot transmit X-linked traits to their sons.
Treatment of Lesch-Nyhan Syndrome
There is no specific treatment available for this disorder. but medications treat the gout and its associated symptoms. Some neurological symptoms improve with the administration of diazepam, carbidopa/levodopa, haloperidol, or phenobarbital.
Lesch Nyhan Syndrome and Nutrition
There are no nutritional deficiencies linked to Lesch-Nyhan syndrome. Some nutrition experts suggest a low purine diet, however, there is no direct or indirect affect of nutrition on the condition.
Some people with Lesch Nyhan syndrome find it difficult to swallow food and some experience frequent vomiting. Patients who have difficulty swallowing food should eat soft foods or foods that have been cut into very small pieces.
(Web): Lesch-Nyhan Syndrome – https://health.nytimes.com/health/guides/disease/lesch-nyhan-syndrome/overview.html
(Web): Treatment · Uric acid · Diet and eating – https://www.lesch-nyhan.org/index.php?section=Treatment&topic=Uric%20acid&subtopic=Diet%20and%20eating