title: Allele frequency of inosine triphosphate pyrophosphatase gene polymorphisms in a Japanese population.
abstract: The enzyme inosine triphosphate pyrophosphatase (ITPase) catalyses the pyrophosphohydrolysis of ITP to IMP. ITPase deficiency is a clinically benign autosomal recessive condition characterised by the abnormal accumulation of ITP in erythrocytes. A deficiency of ITPase may predict adverse reactions to therapy with the thiopurine drug 6-mercaptopurine and its prodrug azathioprine. In this study, we examine the frequencies of ITPA polymorphisms in 100 healthy Japanese individuals. The allele frequency of the 94C > A variant in the Japanese sample was 0.135 (Caucasian allele frequency 0.06). The IV2 + 21A > C polymorphism was not found in Japanese (Caucasian allele frequency 0.130). Allele frequencies of the 138G > A, 561G > A and 708G > A polymorphisms were 0.57, 0.18 and 0.06 respectively in the Japanese population, and with the exception of the 138G > A polymorphism, similar to allele frequencies in Caucasians.
authors.affiliation: Purine Research Unit, Department of Chemical Pathology, Guy's and St. Thomas' Hospitals, London, UK.
authors.forename: A M
authors.initials: AM
authors.lastname: Marinaki
authors.forename: S
authors.initials: S
authors.lastname: Sumi
authors.forename: M
authors.initials: M
authors.lastname: Arenas
authors.forename: L
authors.initials: L
authors.lastname: Fairbanks
authors.forename: S
authors.initials: S
authors.lastname: Harihara
authors.forename: K
authors.initials: K
authors.lastname: Shimizu
authors.forename: A
authors.initials: A
authors.lastname: Ueta
authors.forename: J A
authors.initials: JA
authors.lastname: Duley
mesh_terms: D000483:Alleles; D000963:Antimetabolites / Q000627:therapeutic use; D044466:Asian People; D001379:Azathioprine / Q000627:therapeutic use; D004912:Erythrocytes / Q000201:enzymology; D005787:Gene Frequency; D005808:Genes, Recessive; D014644:Genetic Variation; D006801:Humans; D006868:Hydrolysis; D007564:Japan; D015122:Mercaptopurine / Q000627:therapeutic use; D019384:Nucleic Acid Synthesis Inhibitors / Q000627:therapeutic use; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D011755:Pyrophosphatases / Q000235:genetics*; D044465:White People; D000097630:Inosine Triphosphatase
chemical_list: D000963:Antimetabolites; D001379:Azathioprine; D015122:Mercaptopurine; D019384:Nucleic Acid Synthesis Inhibitors; D011755:Pyrophosphatases; D000097630:Inosine Triphosphatase