A diagnosis of breast cancer, irrespective of other personal cancer history, was reported more frequently in women with MSH6 or PMS2 PVs (MSH6: 30%, 42/140; PMS2: 35.5%, 44/124) compared to women with MLH1 or MSH2 PVs (MLH1: 10.8%, 7/65; MSH2: 14.9%, 14/94) (p < 0.001) (Figure 1a). This evidence concerns the gene MSH6 and breast cancer.