UNLABELLED: This study provides the first analysis of the TPMT mutant allele frequency in a sample of the Jordanian population and indicates that TPMT*3A is the most common allele in Jordanian subjects. PURPOSE: thiopurine methyltransferase TPMT catalyses the S-methylation of thiopurine drugs such as 6-mercaptopurine, 6-thioguanine, and azathiopurine. Thiopurine methyltransferase (TPMT) polymorphisms are the major determinants of interindividual differences in the severe haematological toxicity of 6-mercaptopurine. Several variants in the TPMT gene have been identified that correlate with a low activity phenotype. Four variant alleles, TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C, are responsible for over 80% of the low or undetectable enzyme activity. The allelic frequency of TPMT variants has been established in many populations. METHODS: In this study, the frequencies of four (TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C) variants were investigated in 169 healthy Jordanian men (18-45 years of age). Single nucleotide polymorphisms (SNPs) were genotyped using the Sequenom MassARRAY technology (Sequenom; San Diego, CA, USA). RESULTS: TPMT*3A and TPMT*3C were the only deficiency alleles detected in the Jordanian population with an allele frequency of 0.59% and 0.30% respectively. The TPMT*3A allele frequency is found to be lower than in the European Caucasian population. CONCLUSION: TPMT*3A and TPMT*3C were the only deficiency alleles detected in the Jordanian population with an allele frequency of 0.59% and 0.30% respectively. The TPMT*3A allele frequency is found to be lower than in the European Caucasian population.
UNLABELLED: This study provides the first analysis of the TPMT mutant allele frequency in a sample of the Jordanian population and indicates that TPMT*3A is the most common allele in Jordanian subjects. PURPOSE:thiopurine methyltransferaseTPMT catalyses the S-methylation of thiopurine drugs such as 6-mercaptopurine, 6-thioguanine, and azathiopurine. Thiopurine methyltransferase (TPMT) polymorphisms are the major determinants of interindividual differences in the severe haematological toxicity of 6-mercaptopurine. Several variants in the TPMT gene have been identified that correlate with a low activity phenotype. Four variant alleles, TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C, are responsible for over 80% of the low or undetectable enzyme activity. The allelic frequency of TPMT variants has been established in many populations. METHODS: In this study, the frequencies of four (TPMT*2, TPMT*3A, TPMT*3B and TPMT*3C) variants were investigated in 169 healthy Jordanian men (18-45 years of age). Single nucleotide polymorphisms (SNPs) were genotyped using the Sequenom MassARRAY technology (Sequenom; San Diego, CA, USA). RESULTS:TPMT*3A and TPMT*3C were the only deficiency alleles detected in the Jordanian population with an allele frequency of 0.59% and 0.30% respectively. The TPMT*3A allele frequency is found to be lower than in the European Caucasian population. CONCLUSION:TPMT*3A and TPMT*3C were the only deficiency alleles detected in the Jordanian population with an allele frequency of 0.59% and 0.30% respectively. The TPMT*3A allele frequency is found to be lower than in the European Caucasian population.
Authors: H L Tai; E Y Krynetski; C R Yates; T Loennechen; M Y Fessing; N F Krynetskaia; W E Evans Journal: Am J Hum Genet Date: 1996-04 Impact factor: 11.025
Authors: Ana Teresa P Carvalho; Barbara C Esberard; Renata S B Fróes; Davy C M Rapozo; Ana B Grinman; Tatiana A Simão; Juliana C V C Santos; Antonio José V Carneiro; Luis Felipe Ribeiro-Pinto; Heitor S P de Souza Journal: World J Gastroenterol Date: 2014-03-28 Impact factor: 5.742