[Genetic predisposition for breast cancer: BRCA1 and BRCA2 genes].

The discovery of genes BRCA1 and BRCA2 has led to the introduction of genetic tests more complex every time for the evaluation of the hereditary cancer risk, among others. In the present paper we explore the criteria to decide when to run the testing for the genes, as well as the implications for the treatment of patients who are identified with them.