title: Distribution of CYP2C19*2 and CYP2C19*3 polymorphisms in Venezuelan populations with different admixture.
abstract: BACKGROUND
  The conquest and colonization of Venezuela generated very heterogeneous populations as a product of admixture; for this reason, the distribution of polymorphisms of the CYP2C19 gene was studied in various Venezuelan populations.
  
  
  METHODS
  Two hundred and eighty-one individuals, from three Venezuelan populations with different admixtures, were genotyped for CYP2C19*2 and CYP2C19*3 polymorphisms. Differences between groups were analysed using a chi-square test of heterogeneity and association of allele frequencies with the level of genetic admixture was performed using a principal component analysis (PCA). No significant differences in distribution of alleles, genotypes and phenotypes were found between the populations studied.
  
  
  RESULTS
  In Venezuela, high frequencies of the alleles CYP2C19*2 and CYP2C19*3 were found compared with Europeans, Africans and Latin Americans, similar to those reported in Asia. PCA analysis suggested that the presence of alleles CYP2C19*2 and CYP2C19*3 is associated with the indigenous component in the Venezuelan populations studied.
  
  
  CONCLUSIONS
  Future studies are needed to confirm this association. High frequencies of intermediate metabolizers (20-38%) and of poor metabolizers (2-7%) were observed, similar to values reported for Asians and higher than those reported for South Americans. This is the first study evaluating CYP2C19 polymorphisms in the Venezuelan general population.
authors.affiliation: Laboratorio de Genética Humana, Centro de Medicina Experimental, Instituto Venezolano de Investigaciones Científicas, Caracas 1020 A, Venezuela. dcastro@ivic.gob.ve
authors.forename: Dinorah
authors.initials: D
authors.lastname: Castro de Guerra
authors.forename: Sara
authors.initials: S
authors.lastname: Flores
authors.forename: Mary Helen
authors.initials: MH
authors.lastname: Izaguirre
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics* / Q000378:metabolism; D016009:Chi-Square Distribution; D065731:Cytochrome P-450 CYP2C19; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D010641:Phenotype; D011110:Polymorphism, Genetic; D025341:Principal Component Analysis; D014687:Venezuela
chemical_list: D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19