Our study shows that -26 5' UTR polymorphism in BRCA2 can modulate the fine-tuned regulation of the multifunctional gene BRCA2 and renders risk or protection according to the genotype status in the sporadic form of breast cancer, which is further influenced by the germline genetic backgrounds of codon 72 polymorphism of p53. This evidence concerns the gene TP53 and breast carcinoma.