Although showing that HRD assays may have predictive value for response to platinum chemotherapy and PARP inhibitors, their ultimate role in selecting patients that may benefit from these drugs is unclear [48–51], especially as the indications for PARP inhibitors have broadened beyond patients with germline BRCA mutations to include patients with HRD from other causes and even to other ovarian cancers without identifiable defects in DNA repair. This evidence concerns the gene PARP1 and ovarian cancer.