Overall, 181 BRCA1 PV carriers were diagnosed with BC prior to clinic entry at a mean age of 42.3 ± 11.0 years, median 40.9 years, and of BRCA2 PV carriers, 87 were diagnosed with BC before clinic entry at a mean age of 48.7 ± 11 years (p = 0.00015). Here, BRCA1 is linked to breast cancer.