CHEK2 and breast cancer: Other genes such as ATM (Ataxia telangiectasia mutated), CHEK2 (Checkpoint kinase 2), BARD1 (BRCA1-Associated RING Domain 1), BRIP1 (BRCA1-Interacting Protein 1), NBN (Nibrin), RAD51C (RAD51 Paralog C), RAD51D, and NF1 (Neurofibromin 1) with pathogenic mutations have twofold to fourfold increased risk for breast cancer [163].