Similar patterns were observed for SNPs rs3803662 in TOX3/TNRC9 and rs4973768 in SLC4A7/NEK10 in which the associations were predominantly with ER-positive breast cancer for both BRCA1 and BRCA2 mutation carriers, in line with results from studies of breast cancer in the general population [18,21,27]. Here, SLC4A7 is linked to breast cancer.