study of the regulatory promoter polymorphism (?938c>a) of b?cell lymphoma 2 gene in breast cancer patients of mazandaran province in northern iran

background: the incidence rate of breast cancer has been dramatically increasing since the last decade in iran, and it is now one of the most common female malignant tumors. b?cell lymphoma 2 (bcl2) family is the most important regulator of apoptosis, and ?938c>a single nucleotide polymorphism (snp) of bcl2 gene promoter has been demonstrated to influence breast cancer susceptibility. in this research, we study the effect of ?938c>a allelic variants on breast cancer risk in mazandaran province at the north of iran. materials and methods: this analysis performed on 120 breast cancer patients who underwent surgery in some referenced hospitals at mazandaran province along with 130 healthy individuals as a control. dna extracted from peripheral blood samples was applied in polymerase chain reaction?single?strand conformation polymorphism analysis to determine ?938c>a genotype. the association of the ?938c>a genotype and breast cancer risk as well as clinicopathological characters were analyzed by logistic regression method. results: results showed that genotype frequency of aa, ac, and cc genotypes was 10%, 62%, and 28% for case and 28%, 50%, and 22% in control group, respectively. in the logistic regression model, bcl2 ? 938c/a variant genotype aa was associated with a decreased risk of breast cancer ( p = 0.041) by 0.31?fold (odds ratio = 0.31, confidence interval = 0.091–0.909) compared to cc genotype. however, no significant association found between ?938c>a genotype and clinicopathological characters. conclusion: the study showed that aa genotype of bcl2 gene (?938c>a) is associated with decreased susceptibility to breast cancer. hence, investigating the ?938c>a snp of bcl2 gene promoter could be an appropriate molecular marker to determine individual sensitivity to breast cancer.