Ethnic differences in genetic polymorphisms of CYP2D6, CYP2C19, CYP3As and MDR1/ABCB1

Drug Metab Pharmacokinet. 2004 Apr;19(2):83-95. doi: 10.2133/dmpk.19.83.


Metabolic capacities for debrisoquin, sparteine, mephenytoin, nifedipine, and midazolam, which are substrates of polymorphic CYP2D6, CYP2C19, and CYP3A, have been reported to exhibit, in many cases, remarkable interindividual and ethnic differences. These ethnic differences are partly associated with genetic differences. In the case of the drug transporter ABCB1/MDR1, interindividual differences in its transporter activities toward various clinical drugs are also attributed to several ABCB1/MDR1 genetic polymorphisms. In this review, the existence and frequency of various low-activity alleles of drug metabolizing enzymes as well as populational drug metabolic capacities are compared among several different races or ethnicities. Distribution of nonsynonymous ABCB1/MDR1 SNPs and haplotype frequency in various races are summarized, with the association of nonsynonymous SNPs with large functional alterations as a rare event.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • ATP Binding Cassette Transporter 1
  • ATP-Binding Cassette Transporters / genetics*
  • Aryl Hydrocarbon Hydroxylases / genetics*
  • Cytochrome P-450 CYP2C19
  • Cytochrome P-450 CYP2D6 / genetics*
  • Cytochrome P-450 CYP3A
  • Ethnicity*
  • Genes, MDR / genetics*
  • Humans
  • Mixed Function Oxygenases / genetics*
  • Oxidation-Reduction
  • Oxidoreductases, N-Demethylating / genetics*
  • Polymorphism, Genetic / genetics


  • ATP Binding Cassette Transporter 1
  • ATP-Binding Cassette Transporters
  • Mixed Function Oxygenases
  • Aryl Hydrocarbon Hydroxylases
  • CYP2C19 protein, human
  • Cytochrome P-450 CYP2C19
  • Cytochrome P-450 CYP2D6
  • Cytochrome P-450 CYP3A
  • Oxidoreductases, N-Demethylating