CYP2E1*5B, CYP2E1*6, CYP2E1*7B, CYP2E1*2, and CYP2E1*3 Allele Frequencies in Iranian Populations

Background: CYP2E1 encodes an enzyme which is mainly involved in bioactivation of potential carcinogenssuch as N-nitrosamines. Polymorphisms in the gene have been reported to be associated with cancer. The aim ofthis study was to evaluate genotype distributions and allele frequencies of five CYP2E1 polymorphisms in IranMaterials and
Methods: Two hundred healthy individuals of an Iranian population from the southwest wereincluded in this study. PCR-restriction fragment length polymorphism and Tetra-ARMS PCR methods wereapplied for CYP2E1 genotyping.
Results: The allele frequencies for *5B, *6, *7B, *2, and *3 were calculated tobe 1.5%, 16%, 28.5%, 0%, and 2.75% respectively. Results of this study showed that no significant differencesin genotype and allele frequencies of five single nucleotide polymorphisms with respect to the gender andtribes. The chi-square test showed that the genotype frequencies of CYP2E1*5B were similar to Caucasians,but the distribution of CYP2E1*6 genotypes was similar to Asians. The frequencies of CYP2E1*2 (0%) andCYP2E1*3 (2.75%) alleles were within the range for Caucasians and Orientals. In the case of CYP2E1*7B, thedata werelimited. Accordingly, the results were only compared with Europeans and the comparison showedsignificant differences.
Conclusions: In conclusion, ethnic and geographic differences may explain discrepanciesin the prevalence of CYP2E1 polymorphisms.