ATM and Nijmegen breakage syndrome: Mutations in ATM (Ataxia Telangiectasia Mutated), MRE11, NBS1 (Nijmegen Breakage Syndrome), BRCA1 (Breast Cancer 1), BRCA2 and Ligase 4 cause human syndromes characterized by both CABs and cancer predisposition, highlighting the connection between CABs and cancer [14], [15].