Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.7 (adenine phosphoribosyltransferase)
 692 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A large Arab family affected with the rare X-linked Lesch-Nyhan syndrome is reported on. Two hemizygous boys, two and nine years of age, had the classical biochemical and clinical-neurological syndrome. The activity of erythrocyte hypoxanthine-guanine phosphoribosyltransferase (HGPRT) was below the detectable limit (greater than 0.1% of normal). They were mentally and physically retarded and exhibited spasticity and choreoathetosis; the older of the two also exhibited self-mutilation. The mother and three of her seven daughters, all clinically asymptomatic, were proven to be heterozygous for HGPRT deficiency, by demonstration of an increased rate of de novo purine synthesis in cultured skin fibroblasts. Erythrocyte HGPRT activity was normal in the three heterozygous daughters, but was significantly reduced in the mother. However, in all four heterozygotes, erythrocyte HGPRT/adenine phosphoribosyltransferase ratio was lower than in all other family members. All heterozygotes had blood uric acid levels within the normal range, although higher than in the normal women in the family. The ratio uric acid/creatinine concentration in the urine was significantly elevated in one of the heterozygotes, and in the upper normal limit in two others, indicating excessive purine production.
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PMID:Lesch-Nyhan syndrome in an Arab family. Detection and biochemical manifestation of heterozygosity. 732 17

Lesch-Nyhan syndrome is associated with complete deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT), characterized by hyperuricemia and severe neurological signs. The HPRT gene has been mapped to the q26 region on the long arm of the X-chromosome. We are taking care of a family of Lesch-Nyhan syndrome. A 14-year-old male was noted the growth disturbance at the age of 7 months and self-mutilation behavior characterized by compulsive biting of his lip and fingers at the age of 18 months. In 1987, at the age of 4, he was diagnosed as Lesch-Nyhan syndrome from neurologic signs and hyperuricemia (9.8 mg/dl). Neurological examination revealed mild mental and growth retardation, spasticity and hyperreflexia of lower extremities, choreoathetoid movements of extremities, and compulsive self-mutilation. The HPRT activity in erythrocytes of this patient was 0.02 nmol/min/mg hemoglobin (control value 1.76 +/- 0.06), and adenine phosphoribosyltransferase (APRT) activity was 1.08 nmol/min/mg hemoglobin (control value 0.43 +/- 0.06). Using polymerase chain reaction (PCR) method coupled with direct sequencing, we analyzed the nucleotide sequences of each exon from the genomic DNA as well as the entire HPRT coding region of the cDNA by RT-PCR method. In the HPRT gene from the patient, a guanine to adenine substitution at base position 209 in exon 3 was identified, which resulted in a single amino acid substitution of glycine with glutamic acid at codon 70. The family studies indicated that his mother, sister and grandmother were heterozygotes. PCR-restriction fragment length polymorphism (RFLP) utilizing Mnl I site which created by the mutation, was useful for detection of the mutant gene. We have identified a new missense mutation of the HPRT gene in a Japanese patient. This mutation was reported at the same codon as foreign mutants and mighty be indicative of a location of mutation activity in the HPRT gene.
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PMID:[A Japanese family with Lesch-Nyhan syndrome resulting from a new point mutation in hypoxanthine-guanine phosphoribosyltransferase gene]. 939 32