PVs in these genes show a highly penetrant autosomal dominantinheritance.5 Approximately 50 to 65% ofwomen with a PV in BRCA1, and 40 to 57% of womenwith a PV in BRCA2 will develop BC by age 70, respectively.5BRCA1 and BRCA2 genes are involved in homologous recombination repair; therefore,they act as tumor suppressor genes. This evidence concerns the gene BRCA1 and breast cancer.