Lesch Nyhan Syndrome
Lesch Nyhan Syndrome (LNS) was first reported in 1964 by Michael Lesch and William L. Nyhan. It is a rare disorder located on the x chromosome. It is a sex-linked trait, which means that it is passed from mother to son. This condition can be inherited or occur spontaneously as a result of a genetic mutation. It usually appears once in every 100,000 male births. Since the defective gene is recessive, females almost never exhibit symptoms of the disease. However, they can be carriers of the allele.
Lesch Nyhan is associated with an almost complete absence of the enzyme HGPRTase (hypoxanthene guanine phosphoribosil transferase). This is the enzyme that recycles hypoxanthen and guanine, which are two of the genetic building blocks. When this enzyme is not present, the hypoxanthen and guanine are converted into excessive uric acid. Children around four to six months old are usually diagnosed with LND when orange, sand like uric acid crystals are observed in their diapers. These crystals cause painful urination, arthritis and kidney stones as they build up in various areas of the body.
LNS had many symptoms. Affected people manifest developmental delays, seizures, spacticiy, speech impairment and moderate retardation. The victims usually fall within a 40-80 IQ range. By four years of age the children usually start to exhibit the most well-known symptom of Lesch Nyhan; self-mutilization. The patients begin practicing physical mutilization and hurting themselves through indirect emotional injuries. These behaviors seem to grow as the children get older and become more physically capable of inflicting self-injury and more mentally capable of thinking up new ways to hurt themselves.
Early forms of self-mutilization include biting of the tongue and cheeks, gouging the nose and eyes, rubbing various body parts raw, and banging the head, arms, and legs on things. Another realm of abnormal behavior associated with LNS is manifested as...
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