RAD51C and breast cancer: BC case–control studies to date have identified potentially predisposing RAD51C MS variants, such as p.Gly264Ser4–6, p.Gln143Arg7,8 and pArg258His9,10, while target protein and cellular assays have suggested functional impact and pathogenicity of variants including p.Cys135Tyr and p.Gly264Ser5,8,9.