RESUMO
BACKGROUND: Breast cancer is the most common cancer among women in Iran and the world. Multiple environmental factors and genetic variations such as genetic polymorphisms are of its main causes. p53 gene plays an important role in conserving and sustaining the genome as a tumor suppressing gene. Change and polymorphism at codon 72 of p53 gene are correlated with increased risk of lung, mouth, endometrial, prostate, and colorectal cancers, and could be considered an indicator of susceptibility to breast cancer. METHODS: Twelve studies (1,190 cases and 1,145 control studies with evaluation of three types of Arg/Arg, Arg/Pro, and Pro/Pro genotypes) have been conducted using keywords, such as polymorphism at codon 72, gene p53 polymorphisms, and the relation between polymorphisms and breast cancer, from databases in Iran, including Magiran, Medlibe, Sid, and Iranmedex, as well as Latin databases such as PubMed, Google Scholar, Science Direct, and Scopus. RESULTS: The OR for Arg/Arg is 1.58 (95% CI: 2.45 to 1.01), the OR for Arg/Pro is 0.75 (95% CI: 1.10 to 0.51), and the OR for Pro/Pro is 0.62 (95% CI: 0.93 to 0.42). p53 gene polymorphism at codon 72 is statistically significant in Arg/Arg and Pro/Pro genotypes. CONCLUSIONS: Arg/Arg genotype can be considered as a risk factor for breast cancer, and Pro/Pro genotype can be accounted for as a protective factor against breast cancer.