A higher proportion of invasive ductal carcinoma was identified in patients with GPVs in BRCA1/2 (94.9% and 86.7% in BRCA1 and BRCA2 mutation-carriers vs. 77.9% in non-carriers, p=1.3×10-7 and 0.02), while less ductal carcinoma in situ (DCIS) was found in patients with GPVs in BRCA1 (0% in BRCA1 mutation-carriers vs. 5.5% in non-carriers, p=1.1×10-3). Here, BRCA1 is linked to ductal breast carcinoma in situ.