Association of Genetic polymorphism in estrogen metabolism and susceptibility to Breast cancer

Genome wide association studies have identified single nucleotide polymorphisms (SNP) can affect in development of breast cancer. CYP1A1 gene is a member of the cytochrome P450 superfamily of enzymes which catalyze many reactions involved in drug metabolism and synthesis of estrogen. One of the putative functional polymorphisms in the CYP1A1 gene is CYP1A1*2A or rs 4646903. Many studies have also investigated associations between single nucleotide polymorphisms (SNPs) related to estrogen metabolism and Breast cancer risk. 1.3 Methods:We used case-control study, including 100 cases and 100 controls to genetic analysis. DNA was extracted by salting out method and genotyping was performed using the PCR-RFLP method. Deviation from the Hardy-Weinberg equilibrium was evaluated by chi-square test with 1 degree of freedom. Statistical significance P-value was less than 0.05. Statistical analyses were carried out using IBM SPSS 23.1.4 Results:After counting the genotypes, their percentages in the cancerous specimens were TT (68%), CC (32%), and in control group were TT (86%), CC (14%), respectively. The adjusted ORs (95% CI) for women with the CC genotype were 2.89 (1.43–5.84) and 0.35 (0.17-0.71) for TT genotype. We found a decreased risk of breast cancer among TT genotype in comparison with CC genotype. So, CYP1A1*2A was significantly associated with breast cancer risk. 1.5 Conclusion:In conclusion, Our findings add further evidence to the idea that genetic polymorphisms related to estrogen metabolism may play a role in the development of breast cancer.

Keywords:

Breast cancer , Polymorphism CYP1A1 , rs 4646903