cyp17 mspa1 gene polymorphism and breast cancer patients according to age of onset in cancer institute of iran

background: exposure to endogenous hormones such as estrogen is known as a lifetime breast cancer (bc) risk factor. polymorphisms in genes that are involved in the steroidogenic process, such as cytochrome p450c17alpha ( cyp17) , affect individuals’ susceptibility to bc. in iran, the highest incident of bc is among young women. this study aimed to find prevalence of single nucleotide polymorphisms (snps) in genes such as cyp17 and significant correlation with age-oriented group of breast cancer. methods: in 2016, a case series study was conducted on a total population of 205 patients suffering from breast cancer referred to cancer institute, imam khomeini hospital complex, tehran, iran. this population consisted of 104 cases less than 40 yr old and 101 cases over 40. the genotype variants of cyp17 mspa1 were determined using pcr, followed by rflp. the association of cyp17 mspa1 polymorphisms with the risk of bc in two different age groups was evaluated by calculating odds ratio and 95% confidence intervals using unconditional logistic regression. results: carriers of at least one a2 allele may have higher risk of developing breast cancer at younger age compared to patients with a1/a1 genotype (odds ratio: 1.99, 95% confidence interval: 1.11-3.57, p= 0.02). conclusion: cyp17 gene polymorphisms may have influence on the early onset of breast cancer.