title: Worldwide interethnic variability and geographical distribution of CYP2C9 genotypes and phenotypes.
abstract: BACKGROUND
  Notably differences in CYP2C9 allele frequencies among worldwide populations have been reported, with an interesting low frequency of the CYP2C9*2 allele in Amerindians compared with Admixed and European populations.
  
  
  METHODS
  Literature was searched using the PubMed database and was focused on worldwide original research papers on CYP2C9 alleles and CYP2C9 phenotypes ("predicted" from CYP2C9 genotypes and "measured" metabolic phenotype with a probe drug) among healthy volunteers according to their ethnicity and geographical distribution. Seventy-eight original research articles including a total of 31,978 subjects were identified.
  
  
  CONCLUSIONS
  CYP2C9*2 allele is the most frequent in Caucasian populations (average 14%), with the lowest frequencies for Africans (0.46%), East Asians (0.56%) and Native Americans (1.25%), which is in agreement with the hypothesis about the low prevalence in Amerindians. CYP2C9*3 shows the highest frequency among South Asians (11.7%), while CYP2C9*5 (1.56%) and *8 (4.70%) in African Americans. The predicted poor metabolizers (gPMs) were found overall in a low frequency, with the highest frequency detected for South Asians, in accordance with the CYP2C9*3 frequency in these populations. This study shows the worldwide variability in the CYP2C9 allele frequencies across different ethnic and geographic groups. Data about CYP2C9 "measured" metabolic phenotypes is still limited.
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.|b Genetics Section, School of Biology , University of Costa Rica , 11501-2060 San José , Costa Rica.
authors.forename: Carolina
authors.initials: C
authors.lastname: Céspedes-Garro
authors.affiliation: c Doctorate in Biological and Health Sciences , Metropolitan Autonomous University , 04960 Mexico City , Mexico.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Fricke-Galindo
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.
authors.forename: María Eugenia G
authors.initials: ME
authors.lastname: Naranjo
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.|d Department of General Biology , Federal University of Minas Gerais , 31270-901 Belo Horizonte , Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Rodrigues-Soares
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.
authors.forename: Humberto
authors.initials: H
authors.lastname: Fariñas
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: de Andrés
authors.affiliation: e Department of Biological Systems , Metropolitan Autonomous University , 04960 Mexico City , Mexico.
authors.forename: Marisol
authors.initials: M
authors.lastname: López-López
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.
authors.forename: Eva M
authors.initials: EM
authors.lastname: Peñas-Lledó
authors.affiliation: a CICAB Clinical Research Centre , Extremadura University Hospital and Medical School , Badajoz 06080 , Spain.
authors.forename: Adrián
authors.initials: A
authors.lastname: LLerena
mesh_terms: D065729:Cytochrome P-450 CYP2C9 / Q000235:genetics*; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D010641:Phenotype; D044469:Racial Groups / Q000235:genetics*
chemical_list: D065729:Cytochrome P-450 CYP2C9
keywords: CYP2C9; ethnicity; genotype; phenotype