Reduced prevalence of the C825T polymorphism of the G-protein beta subunit gene in women with breast cancer

Objective: To evaluate the prevalence of the C825T polymorphism in the GNB3 gene in women with and without breast cancer and its possible association with clinical or pathological features of breast disease. Subjects and methods: We included 134 women with breast cancer and a control group of 129 healthy women. The case group responded to a questionnaire on lifestyle, reproductive factors and family history. Clinical data were also evaluated. The risk for cancer was calculated and PCR was carried out for the detection of the polymorphism. Statistical analysis was performed using the package R Environment, with confidence intervals of 95% and a significance level of 5% (p<0.05). Results: The frequency of the TT genotype was significantly greater in women of the control group (30.2%) than women with breast cancer (14.9%) (p=0.02). The polymorphism was not associated with clinical features, age at diagnosis (p=0.07), age at menarche (p=0.17), and age at menopause (p=0.60). The TT genotype did not have a higher frequency in patients with high BMI (p=0.98). The risk for cancer showed no correlation with the presence of the polymorphism. Conclusions: Our data indicate that the C825T polymorphism in the GNB3 gene has no relationship to the risk for breast cancer or the characteristics of the disease. (AU)