Genetic differences in CYP2C19 single nucleotide polymorphisms among four Asian populations

Background This study was designed to compare genetic differences in single -nucleotide polymorphisms of the S-mephenytoin 4'-hydroxylation (CYP2C19) g ene among four Asian populations. Methods. Polymerase chain reaction with r estriction fragment length polymorphism (PCR-RFLP) analysis of CYP2C19 was conducted in Japanese, Chinese, Thai, and Vietnamese populations. All genot ype frequencies were analyzed. Wild-type homozygote and wild-type heterozyg ote genotypes were extensive proton pump inhibitor (PPI) metabolizers. Muta nt-type heterozygote and mutant-type homozygote genotypes were poor PPI met abolizers. Results. No significant differences in CYP2C19 phenotype, calcul ated based on genotype frequencies, (P > 0.05) were found among the four po pulations. Conclusions. Many factors, including CYP2C19 polymorphisms, affe ct the success rate of Helicobacter pylori eradication with PPI-based thera py. We suspect that CYP2C19 polymorphisms may not be the main factor associ ated with differences among these four Asian populations in the success rat es of H. pylori eradication with PPI-based therapy.