BARD1 and breast cancer: The hitherto reported BARD1 mutation screening studies of familial and unselected BC and/or OC cases has led to the identification of numerous BARD1 sequence variants [21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54].