The curves were remarkably similar for each gene, with breast cancer penetrance to 70 and 80 years of 68% (95%CI 65–71%) and 79.5% (95%CI 75–84%) for BRCA1 and 74% (95%CI 71–77%) and 88% (95%CI 85–91%) for BRCA2. Ovarian cancer risk to 70 and 80 years was 60% (95%CI 65–71%) and 65% (95%CI 75–84%) for BRCA1 and 30% (95%CI 25.5–34.5%) and 37% (95%CI 31.5–42.5%) for BRCA2. The penetrance for ovarian cancer was significantly higher for BRCA1 (p < 0.0001), but breast cancer incidence for BRCA2 was borderline significantly higher than for BRCA1 (p = 0.09). This evidence concerns the gene BRCA2 and breast carcinoma.