Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00492 (hypoxanthine-guanine phosphoribosyltransferase)
 2,385 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inherited mutations of a purine salvage enzyme, hypoxanthine guanine phosphoribosyltransferase (HPRT, EC 2.4.2.8; MIM308000), give rise to Lesch-Nyhan syndrome (MIM300322) or HPRT-related gout called as Kelley-Seegmiller syndrome (MIM300323). In contrast with the most severe phenotype of classical Lesch-Nyhan disease (LND), the least severe phenotype is characterized by hyperuricemia without any neurological or behavioral abnormality, and designated HPRT-related hyperuricemia (HRH). In between these two extremes are phenotypes involving hyperuricemia and varying degrees of neurobehavioral abnormality but without self-injury, designated HPRT-related neurological dysfunction (HRND). Marked genetic heterogeneity of HPRT deficiency is well known. More than 300 different mutations in the HPRT gene (HPRT1 which located in Xq26.1), deletion, insertions, duplications, abnormal splicing and point mutations at different sites of the coding region from exons 1 to 9, have been identified.
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PMID:[Deficiencies of hypoxanthine guanine phosphoribosyltransferase (HPRT)]. 1840 16

Inherited mutation of hypoxanthine guanine phosphoribosyltransferase, (HPRT) gives rise to Lesch-Nyhan syndrome or HPRT-related gout. We have identified a number of HPRT mutations in patients manifesting different clinical phenotypes, by analyzing all nine exons of the HPRT gene (HPRT1) from genomic DNA and reverse transcribed mRNA using the PCR technique coupled with direct sequencing. Recently, we detected two novel mutations: a single nucleotide substitution (430C > T) resulting in a nonsense mutation Q144X, and a deletion of HPRT1 exon 1 expressing no mRNA of HPRT. Furthermore, we summarized the spectrum of 56 Japanese HPRT mutations.
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PMID:Molecular analysis of hypoxanthine guanine phosphoribosyltransferase (HPRT) deficiencies: novel mutations and the spectrum of Japanese mutations. 1860 May 6

A deficiency in hypoxanthine guanine phosphoribosyltransferase (HPRT) activity leads to overproduction of uric acid. According to the degree of enzymatic deficiency, a large spectrum of neurologic features can also be observed, ranging from mild or no neurologic involvement to complete Lesch-Nyhan disease. Herein, we describe a patient with hyperuricemia, juvenile-onset gouty arthritis, nephrolithiasis, and mild neurologic symptoms, attributed to a newly identified variant of the hprt gene, c.596T>G, resulting in the amino acid change p.F199C. Residual HPRT activity (8%) protected against severe neurologic involvement in this patient. Modeling of the mutated protein was used to predict the mechanisms that led to partial enzymatic activity. Careful neurologic examination is warranted in juvenile and middle-aged patients with gout, in order to detect mild symptoms that may lead to a diagnosis of HPRT deficiency.
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PMID:Severe gouty arthritis and mild neurologic symptoms due to F199C, a newly identified variant of the hypoxanthine guanine phosphoribosyltransferase. 1956 99

Inherited mutation of hypoxanthine guanine phosphoribosyltransferase (HPRT) gives rise to Lesch-Nyhan syndrome or HPRT-related gout. On the other hand, PRPS1 mutations cause PRPP synthetase superactivity associated with hyperuricemia and gout, sometimes including neurodevelopmental abnormalities. We have identified two mutations in two Lesch-Nyhan families after our last report. One of them, a new single nucleotide substitution (130G>T) resulting in a missense mutation D44Y was detected in exon 2 of HPRT1. RT-PCR amplification showed not only a cDNA fragment with normal size, but also a small amount of shorter fragment skipping exons 2 and 3. The other missense mutation F74L (222C > A) was detected in a Japanese patient but has been reported previously in European families. In four hyperuricemic patients with mild neurological abnormality, no mutations responsible for partial HPRT deficiency were identified in HPRT1. In these four patients, we also performed molecular analysis of PRPS1, but no mutations in PRPP synthetase were found.
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PMID:Molecular analysis of two enzyme genes, HPRT1 and PRPS1, causing X-linked inborn errors of purine metabolism. 2054 9

Mutation of hypoxanthine guanine phosphoribosyltransferase (HPRT) gives rise to Lesch-Nyhan syndrome, which is characterized by hyperuricemia, severe motor disability, and self-injurious behavior, or HPRT-related gout (Kelley-Seegmiller syndrome). The marked heterogeneity of HPRT deficiency is well known, with more than 300 mutations at the HPRT gene locus having been reported (deletions, insertions, duplications, abnormal splicing, and point mutations at different sites of the coding region from exons 1 to 9). We have identified mutations in Asian families with patients manifesting different clinical phenotypes, including rare cases of female subjects, by analyzing all nine exons of the HPRT gene (HPRT1) from genomic DNA and reverse-transcribed mRNA using the polymerase chain reaction technique coupled with direct sequencing. We developed suitable methods to detect the mutations identified from respective families with HPRT deficiency. Then, prenatal genetic diagnoses in HPRT-deficient families were carried out using both mRNA and genomic DNA from chorionic villi or amniotic fluid cells. As shown here in the heterogeneity of HPRT mutations, the spectrum of 70 mutations identified in the Asian population fits the four main conclusions that emerged previously from worldwide analysis.
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PMID:Hypoxanthine guanine phosphoribosyltransferase (HPRT) mutations in the Asian population. 2213 82

Inherited mutation of the purine salvage enzyme, hypoxanthine guanine phosphoribosyltransferase (HPRT) gives rise to Lesch-Nyhan syndrome (LNS) or Lesch-Nyhan variants (LNV). We report a case of two LNS affected members of a family with deficiency of activity of HPRT in intact cultured fibroblasts in whom mutation could not be found in the HPRT coding sequence but there was markedly decreased HPRT expression of mRNA.
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PMID:Lesch-Nyhan syndrome: mRNA expression of HPRT in patients with enzyme proven deficiency of HPRT and normal HPRT coding region of the DNA. 2276 37

Inherited mutation of the purine salvage enzyme, hypoxanthine guanine phosphoribosyltransferase (HPRT) gives rise to Lesch-Nyhan syndrome (LNS) or Lesch-Nyhan variants (LNVs). We report three novel independent mutations in the coding region of HPRT gene: exon 3: c.141delA, p.D47fs53X; exon 5: c.400G>A, p.E134K; exon 7: c.499A>G, p.R167G from three LNS affected male patients.
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PMID:Identification of novel mutations in the human HPRT gene. 2347 2

Disorders of purine and pyrimidine metabolism can result in an array of clinical manifestations including neurologic manifestations. The most commonly cited disorder, in the neurologic realm, is Lesch-Nyhan syndrome which presumably reflects its distinctive feature of self-mutilation. Expansion of our knowledge with molecular genetic methodology has helped to better identify and characterize mutations such as those which occur with the enzyme hypoxanthine guanine phosphoribosyltransferase (HPRT), and this has enhanced our understanding of phenotypical expression of Lesch-Nyhan syndrome and Lesch-Nyhan variants. It is hoped that further elucidation of DNA coding regions and messenger RNA expression will lead to the potential for gene therapy to correct these inborn errors of purine and pyrimidine metabolism.
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PMID:Disorders of purines and pyrimidines. 2436 55

Mutation of hypoxanthine guanine phosphoribosyltransferase (HPRT) gives rise to Lesch-Nyhan syndrome, which is characterized by hyperuricemia, severe motor disability, and self-injurious behavior, or HPRT-related gout with hyperuricemia. Four mutations were detected in two Lesch-Nyhan families and two families with partial deficiency since our last report. A new mutation of G to TT (c.456delGinsTT) resulting in a frameshift (p.Q152Hfs*3) in exon 3 has been identified in one Lesch-Nyhan family. In the other Lesch-Nyhan family, a new point mutation in intron 7 (c.532+5G>T) causing splicing error (exon 7 excluded, p.L163Cfs*4) was detected. In the two partial deficiency cases with hyperuricemia, two missense mutations of p.D20V (c.59A>T) and p.H60R (c.179A>G) were found. An increase of erythrocyte PRPP concentration was observed in the respective phenotypes and seems to be correlated with disease severity.
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PMID:Hypoxanthine guanine phosphoribosyltransferase (HPRT) deficiencies: HPRT1 mutations in new Japanese families and PRPP concentration. 2494 Jun 72


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