Genetic polymorphisms of drug-metabolizing phase I enzymes CYP3A4, CYP2C9, CYP2C19 and CYP2D6 in Han, Uighur, Hui and Mongolian Chinese populations.

We randomly evaluated 672 unrelated, healthy Chinese volunteers (136 Han, 214 Uighur, 164 Hui and 158 Mongolian) to compare CYP3A4, CYP2C9, CYP2C19 and CYP2D6 allele frequencies. Genomic DNA was extracted from peripheral leukocytes and genotyped for CYP3A4*5, CYP3A4*18, CYP2C9*2, CYP2C9*13, CYP2C19*2, CYP2C19*3 and CYP2D6*10 by PCR-restriction fragment length polymorphism analysis (PCR-RFLP). Our results showed that there is no significant difference in the distribution of CYP2C19*3 and CYP3A4*18 genotypes in the Han, Uighur, Hui and Mongolian Chinese populations. The CYP2C9*13/*13 and CYP3A4*5 genotypes were not observed in any of the four Chinese populations. We found a higher incidence of the CYP2C9*2 allele in Uighur populations, compared to the Han, Hui and Mongolian populations. The incidence of the CYP2C19*2 allele in the Han population was not significantly different from that in the Uighur, Hui or Mongolian populations; however, the Uighur population showed significantly lower rates of this allele than the Hui and Mongolian populations, and the Mongolian population had a significantly lower incidence of this allele than the Hui population. There was no significant difference in the presence of the CYP2D6*10 allele in the Mongolian, Han or Hui populations. However, the Uighur population showed significantly lower rates of this allele than the other three populations. These findings provide basic genetic information for further pharmacogenomic investigations in the Chinese population.