Approximately 50% of high-grade serous ovarian cancers are characterized by HR deficiency, which involves mutations in BRCA1/2, the MRN complex (MRE11, RAD50, NBS1), ATM, RAD51C/D, PALB2, BRIP1, BARD1, and other genes (O’Connor, 2015; Moschetta et al., 2016). The gene discussed is RAD50; the disease is ovarian serous adenocarcinoma.