Introduction: The MDM2 gene plays an important role as negative regulator of the p53 tumor suppressor. Data on polymorphisms in the MDM2 gene have revealed associations with cancer, particularly for the rs2279744 promoter polymorphism (309 T > G), which attenuates the P53 pathway and promotes tumorigenesis in the mammary gland.
Material and Methods: We examined the role of the MDM2 309 T > G polymorphism through a comparison of the genotypes of 408 healthy Mexican women with those of 529 Mexican women with breast cancer (BC).
Results: The genotype frequencies of the MDM2 309 T > G polymorphism in controls and BC patients were 25% and 23% for T/T (wild type), 50% in BC and controls for T/G, and 25 and 27% for G/G (polymorphic type), respectively. The obtained odds ratio (OR) was 1.07, with a 95% confidence interval (95% CI) of 0.79-1.45, p = 0.64 for the T/GG/ G genotypes. The association was evident when the distributions of the G/G genotypes in patients exhibiting the following characteristics were compared: breastfeeding >6 months (OR 2.1, 95% CI 1.3-3.4, p = 0.002), obesity (OR 1.8, 95% CI 1.2-2.7, p = 0.003) and high GGT levels (OR 1.7, 95% CI 1.1-2.5, p = 0.012). The genotype G/G of the MDM2 309 T > G. Conclusions: The MDM2 309 T > G polymorphism was associated with BC susceptibility, particularity in breastfeeding, obesity and high GGT levels in the analyzed Mexican population.