Due to the contribution of PARP1 to DNA repair, PARP inhibitors have been extensively tested, and some of them (as well as PARP traps, including olaparib and talazoparib) have been approved for the monotherapies of patients with breast or ovarian cancer characterized by DNA repair deficiencies such as BRCA1 and BRCA2 mutations [47]. The gene discussed is BRCA1; the disease is ovarian cancer.