title: Genotype and allele frequency of CYP2C19*17 in a healthy Iranian population.
abstract: BACKGROUND
  Cytochrome P450 2C19 (CYP2C19) is important in metabolism of wide range of drugs. CYP2C19*17 is a novel variant allele which increases gene transcription and therefore results in ultra-rapid metabolizer phenotype (URM). Distribution of this variant allele has not been well studied worldwide. The aim of present study was to investigate allele and genotype frequencies of CYP2C19*17 in a healthy Iranian population and compare them with other ethnic groups.
  
  
  METHODS
  One hundred eighty healthy unrelated Iranian volunteer took part in this study and were genotyped for CYP2C19 *2, *3, *17 (-3402) by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and CYP2C19*17 (-806) by a nested-PCR assays. The distribution of CYP2C19*17 polymorphism in Iranian population was then compared with other ethnic groups.
  
  
  RESULTS
  The CYP2C19*17 allele frequency was 21.6% in Iranian population. Among studied subjects 5.5% were homozygous for CYP2C19*17 and phenotyped as ultra-rapid metabolizers; 28.8% were genotyped as CYP2C19*1*17 (extensive metabolizers) and 3.3% as CYP2C19*2*17 (intermediate metabolizers).
  
  
  CONCLUSIONS
  The CYP2C19*17 genetic distribution in Iranian population is similar to Middle East or European countries. The high frequency of CYP2C19*17 in Iranian population highlights the importance of this new variant allele in metabolism of CYP2C19 substrates. Thus, future association studies are required to reveal clinical consequence of this genetic polymorphism in carrier individuals.
authors.affiliation: PhD candidate, Biopharmaceutics and Pharmacokinetics Division, Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical sciences, Tehran, Iran. payan@razi.tums.ac.ir.
authors.forename: Maryam
authors.initials: M
authors.lastname: Payan
authors.affiliation: Professor of Immunology, Immunology Research Center (IRC), Iran University of Medical Sciences, Tehran, Iran. nadertajik@yahoo.com , tajik.n@iums.ac.ir.
authors.forename: Nader
authors.initials: N
authors.lastname: Tajik
authors.affiliation: Professor, Biopharmaceutics and Pharmacokinetics Division, Department of Pharmaceutics, Faculty of Pharmacy, Tehran University of Medical sciences, Tehran, Iran. rouini@tums.ac.ir.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Rouini
authors.affiliation: Professor, Department of Pharmacology and Toxicology, Faculty of Pharmacy, Tehran University of Medical sciences, Tehran, Iran. mhghahremani@razi.tums.ac.ir.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Ghahremani
keywords: CYP2C19; Genotyping; Iranian; Polymerase chain reaction; Polymorphism