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

  • Shahriary, Ghazaleh Mohammadzadeh (Department of Genetics, Faculty of Mathematics, Shaheed Chamran University) ;
  • Galehdari, Hamid (Department of Genetics, Faculty of Mathematics, Shaheed Chamran University) ;
  • Jalali, Amir (Department of Pharmacology and Toxicology, School of Pharmacy and Toxicology Research Center, Jundishapur University of Medical Sciences Center) ;
  • Zanganeh, Fatemeh (Department of Pharmacology and Toxicology, School of Pharmacy, Shaheed Beheshti University of Medical Sciences) ;
  • Alavi, Seyed Mohammad Reza (Department of Statistics, Faculty of Mathematics, Shaheed Chamran University) ;
  • Aghanoori, Mohammad Reza (Department of Medical Genetics, Shiraz University of Medical Sciences)
  • Published : 2012.12.31


Background: CYP2E1 encodes an enzyme which is mainly involved in bioactivation of potential carcinogens such as N-nitrosamines. Polymorphisms in the gene have been reported to be associated with cancer. The aim of this study was to evaluate genotype distributions and allele frequencies of five CYP2E1 polymorphisms in Iran Materials and Methods: Two hundred healthy individuals of an Iranian population from the southwest were included in this study. PCR-restriction fragment length polymorphism and Tetra-ARMS PCR methods were applied for CYP2E1 genotyping. Results: The allele frequencies for $^*5B$, $^*6$, $^*7B$, $^*2$, and $^*3$ were calculated to be 1.5%, 16%, 28.5%, 0%, and 2.75% respectively. Results of this study showed that no significant differences in genotype and allele frequencies of five single nucleotide polymorphisms with respect to the gender and tribes. 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%) and $CYP2E1^*3$ (2.75%) alleles were within the range for Caucasians and Orientals. In the case of $CYP2E1^*7B$, the data werelimited. Accordingly, the results were only compared with Europeans and the comparison showed significant differences. Conclusions: In conclusion, ethnic and geographic differences may explain discrepancies in the prevalence of CYP2E1 polymorphisms.


Cytochrome P450;polymorphism;genotyping;allele frequency;Iranian population


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