BRCA1 and breast cancer: Compared with controls, cases had a shorter mean (SD) duration of breastfeeding (67.0 [54.3] vs 54.3 [39.4] months); higher proportions of benign breast disease history (3.3% [23] vs 5.1% [51]), breast cancer family history (2.0% [14] vs 3.6% [36]), and alcohol intake (4.8% [33] vs 8.2% [82]); more PVs in genes (eg, in BRCA1: 0 vs 27 [2.7%]); and greater mean (SD) PRS (0.182 [0.314] vs 0.268 [0.317]).