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

A previously undescribed nucleotide substitution at codon 51 (CGA to TGA) has been identified using the polymerase chain reaction technique in hypoxanthine guanine phosphoribosyltransferase (HPRT) cDNA; this is the first molecular evidence for a point mutation in a Japanese patient with Lesch-Nyhan syndrome. The present mutation is the 19th nucleotide substitution identified as a germ-line mutation at this locus and the second mutation generating a stop codon. The position of the nucleotide substitution is exactly the same as a previously described mutation HPRTToronto, indicating for the first time that nucleotide substitutions at the same position in the sequence of HPRT can generate different mutant alleles, one causing a partial deficiency and the other a complete deficiency. Although the type of nucleotide substitution is different between the two cases, a single base position has twice become the target of a mutation. However, the calculation of the probability of finding substitution mutations at the same base position in the coding region of hprt indicates that there is no evidence for the presence of a hot spot for substitution mutations in the human hprt germ line.
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PMID:Hypoxanthine guanine phosphoribosyltransferase deficiency: nucleotide substitution causing Lesch-Nyhan syndrome identified for the first time among Japanese. 232 82

Complete deficiency of hypoxanthine guanine phosphoribosyltransferase (HPRT) causes Lesch-Nyhan syndrome. We examined the HPRT gene mutation for prenatal diagnosis in a Japanese family. A single nucleotide substitution of C to T in exon 3 was identified by direct sequencing analysis of the HPRT gene of a Lesch-Nyhan patient. This substitution resulted in a nonsense mutation, CGA (Arg) to TGA (stop), at codon 51. Utilizing an Xho I restriction site which was lost in the mutation as an indicator, a family study showed that the mother was heterozygous, but the grandmother normal. By the same method, prenatal genetic diagnosis was performed using chorionic villus samples (CVS), and showed that the fetus had the mutant allele.
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PMID:Molecular analysis of a Japanese family with Lesch-Nyhan syndrome: identification of mutation and prenatal diagnosis. 894 18