A Novel Single Nucleotide Polymorphism (SNP) of the CYP2C19 Gene in a Japanese Subject with Lowered Capacity of Mephobarbital 4′-Hydroxylation

Abstract

  We sequenced all nine exons and exon-intron junctions of the cytochrome P450 2C19 (CYP2C19) gene from a Japanese subject with a lowered capacity of CYP2C19-mediated 4′-hydroxylation after an oral administration of mephobarbital. We found a novel single nucleotide polymorphism (SNP) of CYP2C19 gene as follows: SNP, 040110MoritaJ001; GENENAME: CYP2C19; ACCESSION NUMBER: NT_030059.8; LENGTH; 25 bases; 5′-GAGGGCCTGGCCC/TGCATGGAGCTGT-3′. The SNP (168946C>T) induced an amino acid alteration (Arg442Cys) located in exon 9 close to the heme-binding region of CYP2C19, which may result in the decrease in the catalytic properties of CYP2C19. A new allele having this SNP was designated as CYP2C19*16.