Functional characterization of 17 CYP2D6 allelic variants (CYP2D6.2, 10, 14A-B, 18, 27, 36, 39, 47-51, 53-55, and 57).

Cytochrome P450 2D6 (CYP2D6) is an enzyme of potential importance for the metabolism of drugs used clinically, and it exhibits genetic polymorphism with interindividual differences in metabolic activity. To date, 21 CYP2D6 allelic variants have been identified in the Japanese population. The aim of this study was to investigate the functional characterization of CYP2D6 variants identified in Japanese subjects.

Functional characterization of 23 allelic variants of thiopurine S-methyltransferase gene (TPMT*2 - *24).

Objective: Thiopurine S-methyltransferase (TPMT) is an enzyme responsible for the detoxification of the widely used thiopurine drugs. TPMT is genetically polymorphic and is associated with large interindividual variations in thiopurine drug toxicity and therapeutic efficacy. In this study, we performed an in-vitro analysis of TPMT variant alleles, namely, TPMT*2, *3A, *3B, *3C, *5, *6, *7, *8, *9, *10, *11, *12, *13, *14, *16, *17, *18, *19, *20, *21, *22, *23, and *24.

Functional characterization of human xanthine oxidase allelic variants.

Objective: Xanthine oxidase (XO) catalyzes the oxidation of endogenous and exogenous purines and pyrimidines. In this study, we speculated that individual variations in XO activity are caused by genetic variations in the XO gene.

Methods: To investigate the genetic variations in XO in 96 Japanese participants, denaturing high-performance liquid chromatography was used.

A novel single nucleotide polymorphism of the human methylenetetrahydrofolate reductase gene in Japanese individuals.

The genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR) have been associated with increased toxicity of methotrexate (MTX), a folic acid antagonist that is widely used to treat cancer and immunosuppressive disorders such as rheumatoid arthritis. In this study, we analyzed all the exons and exon/intron junctions of the MTHFR gene from 200 Japanese individuals. We detected a novel single nucleotide polymorphism (SNP) 148C>T (Arg46Trp) in exon 1.