Zeinab Tavakkol Afshari - Immunogenetic and Cell Culture Department, Immunology Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Amin Reza Nikpoor - Immunogenetic and Cell Culture Department, Immunology Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Jalil Tavvakol Afshari - Immunogenetic and Cell Culture Department, Immunology Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Rashin Ganjali - Immunogenetic and Cell Culture Department, Immunology Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Parvaneh Sanglakh Ghoochan Atigh - Biochemistry Department, Mashhad Payame Noor University, Mashhad, Iran
Fatemeh Homaei Shandiz - Cancer Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
Khadijeh Jamialahmadi - Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

Background: Breast cancer is one of the most common cancers among women worldwide. Tumor protein ۵۳ (TP۵۳) and its regulator the mouse double murine ۲ (MDM۲) have important roles in tumorigenesis by playing key roles in cell division and response to DNA damage. MDM۲ SNP۳۰۹ T>G (rs۲۲۷۹۷۴۴) polymorphism in the promoter region of MDM۲ gene can cause dysfunction and inactivation of TP۵۳ 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. Material: A case-control study with ۱۲۸ breast cancer patients and ۱۴۳ healthy women was conducted. PCR-ARMS was performed to assess the MDM۲ SNP۳۰۹ T>G (rs۲۲۷۹۷۴۴) polymorphism. Results: The GG Genotype frequency between patients and controls showed no significant association between this polymorphism with breast cancer risk (p=۰.۱۱۶, OR [۹۵% CI]: ۱.۲۶۷ [۰.۶۱۶, ۲.۶۰۳]). Also, G allele frequency was not associated with breast cancer risk in studied population (p=۰.۱۴۳, OR [۹۵% CI]: ۱.۳۲۶ [۰.۹۰۸, ۱.۹۳۵]). For this polymorphism, a significant difference of ۸.۰ years in the average age of cancer diagnosis was observed between TT and TG carriers (۴۰.۵۷ versus ۴۸.۱۵ years, p = ۰.۰۲۹). Conclusion: The results of this study suggest that the SNP۳۰۹ T>G polymorphism in the MDM۲ gene may not be associated with the risk of breast cancer in an Iranian population

Breast cancer, Case-control study, Mouse double murine ۲ (MDM۲), Polymorphism