title: Canadian Native Indians exhibit unique CYP2A6 and CYP2C19 mutant allele frequencies.
abstract: Many human cytochromes P450 (CYP) enzymes are polymorphically expressed, resulting in interindividual and interethnic differences in the metabolism of substrate drugs. Little is known about the genetic variation of CYP enzymes in Canadian Native Indians. We therefore determined the CYP2C19 and CYP2A6 mutant allele frequencies in 159 Canadian Native Indians and compared them with white and Asian subjects. Canadian Native Indians differed significantly from both white and Asian populations in allelic patterns of both CYP2C19 (19.1% CYP2C19*2 and 0% CYP2C19*3) and CYP2A6 (0.9% CYP2A6*2 and 13.9% CYP2A6*3). In addition, analysis of the Canadian Native Indian data suggested that there may be an association between the presence of the CYP2C19 and CYP2A6 mutant alleles such that the co-occurrence of these 2 alleles is higher than would be predicted on the basis of their individual frequencies in this population.
authors.affiliation: Department of Pharmacology, University of Toronto, Ontario, Canada.
authors.forename: M P
authors.initials: MP
authors.lastname: Nowak
authors.forename: E M
authors.initials: EM
authors.lastname: Sellers
authors.forename: R F
authors.initials: RF
authors.lastname: Tyndale
mesh_terms: D000483:Alleles; D001189:Aryl Hydrocarbon Hydroxylases; D044466:Asian People / Q000235:genetics; D002170:Canada; D065637:Cytochrome P-450 CYP2A6; D065731:Cytochrome P-450 CYP2C19; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D007198:Indians, North American / Q000235:genetics*; D008297:Male; D006899:Mixed Function Oxygenases / Q000235:genetics*; D009154:Mutation; D044465:White People / Q000235:genetics
chemical_list: D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D001189:Aryl Hydrocarbon Hydroxylases; C585710:CYP2A6 protein, human; C045793:CYP2C19 protein, human; D065637:Cytochrome P-450 CYP2A6; D065731:Cytochrome P-450 CYP2C19