Lack of an Association between a Functional Polymorphism in the MDM2 Promoter and Breast Cancer in Women in Northeast Iran

Breast cancer is one of the most common cancers among women worldwide. Tumor protein 53 (TP53) and its regulator the mouse double murine 2 (MDM2) have important roles in tumorigenesis by playing key roles in cell division and response to DNA damage. MDM2 SNP309 T>G (rs2279744) polymorphism in the promoter region of MDM2 gene can cause dysfunction and inactivation of TP53 which promote tumor progression as a result. The aim of this study was to investigate the association between this polymorphism and risk of breast cancer in northeastern Iranian population. A case-control study with 128 breast cancer patients and 143 healthy women was conducted. PCR-ARMS was performed to assess the MDM2 SNP309 T>G (rs2279744) polymorphism. The GG Genotype frequency between patients and controls showed no significant association between this polymorphism with breast cancer risk (p=0.116, OR [95% CI]: 1.267 [0.616, 2.603]). Also, G allele frequency was not associated with breast cancer risk in studied population (p=0.143, OR [95% CI]: 1.326 [0.908, 1.935]). For this polymorphism, a significant difference of 8.0 years in the average age of cancer diagnosis was observed between TT and TG carriers (40.57 versus 48.15 years, p = 0.029). The results of this study suggest that the SNP309 T>G polymorphism in the MDM2 gene may not be associated with the risk of breast cancer in an Iranian population