BRCA2 and breast cancer: Among women with ER-positive BC, BRCA2 was the dominant BRCA PV type, ranging from 62.3% among the nulliparous group to 75.0% among the PPBC at less than 5 years group; the frequency distributions of BRCA2 among PPBC 5 to less than 10 years and parous BC at 10 years or more groups were both 70.3% (P = .56).