Three Novel Single Nucleotide Polymorphisms of the Human Thiopurine S-Methyltransferase Gene in Japanese Individuals

Summary:In this study, the entire coding sequence and the exon-intron junctions of the thiopurine S-methyltransferase (TPMT) gene from 200 Japanese individuals were screened for mutation. Three novel single nucleotide polymorphisms (SNPs) were identified-106G > A in exon 3 (Gly36Ser, *20 allele), 967A > G in 3'-untranslated region, and -87C > T in intron 8. The allele frequencies were 0.003 for 106G > A, 0.003 for 967A > G, and 0.010 for IVS8 -87C > T. In addition, the three known SNPs, 474 T > C (Ile158Ile), 719A > G (Tyr240Cys, *3C allele), and IVS4 + 35C > T were detected at frequencies of 0.299, 0.010, and 0.421, respectively.