RT Journal Article SR Electronic T1 CYP3A5 GENETIC POLYMORPHISMS IN DIFFERENT ETHNIC POPULATIONS JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 884 OP 887 DO 10.1124/dmd.105.003822 VO 33 IS 7 A1 Roy, Jean-Nicholas A1 Lajoie, Julie A1 Zijenah, Lynn S. A1 Barama, Azemi A1 Poirier, Charles A1 Ward, Brian J. A1 Roger, Michel YR 2005 UL http://dmd.aspetjournals.org/content/33/7/884.abstract AB Cyp3A5 activity varies within any given ethnic population, suggesting that genetic variation within the Cyp3A5 gene may be the most important contributor to interindividual and interracial differences in Cyp3A-dependent drug clearance and response. The full extent of Cyp3A5 polymorphism in a white and an indigenous African population was analyzed using DNA direct sequencing procedures. The presence of 10 and 12 single nucleotide polymorphisms was detected in the white and African samples, respectively. Thirteen novel mutations occurring at low frequencies were identified in these populations. Significant differences were observed in the distribution of Cyp3A5*3, Cyp3A5*6, and Cyp3A5*7 alleles among white and African populations. The frequency of Cyp3A5*3 allele in white Canadians (∼93%) is higher than in Zimbabweans (77.6%) (p < 0.001). In contrast, Cyp3A5*6 and Cyp3A5*7 alleles are relatively frequent in African subjects (10–22%) but absent in white subjects (p < 0.001). These differences may reflect evolutionary pressures generated by environmental factors in geographically distinct regions. However, the genetic polymorphism of Cyp3A5 alone does not explain the interindividual differences in Cyp3A-mediated metabolism. The American Society for Pharmacology and Experimental Therapeutics