Cytochrome P450 1A1 and cytochrome P450 2E1 gene polymorphisms in Guangzhou Hans

Objective: To determine the distribution of cytochrome P450 1A1 (CYP1A1) and cytochrome P450 2E1 (CYP2E1) gene polymorphisms in Guangzhou Hans. Methods: A total of 150 healthy Guangzhou Hans were studied with PCR-RFLP and ASA techniques. Current results were compared with the data on other ethnic groups. Results: In the 150 individuals tested, the frequencies of the ml(Msp I -) and m2(Msp I +) alleles of the Msp I polymorphic site in the 3' non-coding region of the CYP1A1 gene were found to be 62.33% and 37.67%, respectively. The observed frequencies of the m1m1, m1m2 and m2m2 genotypes were found to be 40%, 44.67% and 15.33%, respectively, which met Hardy-Weinberg equilibrium. The frequencies of the A and G alleles of the exon 7 A4889G polymorphic site in the CYP1A1 gene were found to be 79% and 21%, respectively. The observed frequencies of the AA, AG and GG genotypes were found to be 62.67%, 32.67% and 4.66%, respectively, which met Hardy-Weinberg equilibrium. A close linkage between the Msp I polymorphism and exon7 A4889G polymorphism was observed in Guangzhou Hans (X²= 62. 2358, P<0.005). The frequencies of the C1 (Rsa I +, Pst I -) and C2(Rsa I -, Pst I +) alleles of the Rsa I polymorphic site in the 5'-flanking region of the CYP2E1 gene were found to be 85.3% and 14.7%, respectively. The observed frequencies of the C1C1, C1C2 and C2C2 genotypes were found to be 67.3%, 29.3%, and 3.4%, respectively, which met Hardy-Weinberg equilibrium. Conclusion: The frequencies of the CYP1A1 and CYP2E1 gene polymorphisms in Guangzhou Hans were similar to those in Japanese population, but were significantly different from those in European populations.