[Population genetic analysis of the association between the BRCA1 and P53 gene polymorphisms and the risk of sporadic breast cancer].

Polymorphism of two tumor-suppressor genes, BRCA1 and P53, was examined. DNA was extracted from blood leukocytes of the women affected with breast cancer (N = 151) and of the women with no clinical symptoms of tumor diseases (N = 191). Typing of the polymorphic variants was performed using PCR-RFLP method. It was demonstrated that the genetic structure of the patient group (taking into consideration BRCA1 and P53 polymorphic variants) differed from that of the control group. The group of genotypes, found exclusively among the patients, as well as the group of "resistant" genotypes revealed predominantly among the controls, was described. Detection of the genotype A1A1 B1B1 S1S1 C1C1 F1F1 J2J2, whose frequency in control group was eight times higher than in the patient group, was an additional confirmation of the existence of "resistant" genotypes. These findings point to the association between the combinations of the BRCA1 and P53 allelic variants and the risk of breast cancer.