As testing has broadened to include newer inherited cancer genes, studies have suggested that mutations which shorten the protein (“truncating mutations”) in the RAD51D gene are associated with ovarian cancer. However, a recent study examined ovarian cancer risks for a “non-truncating” change (a single base pair within the gene is changed which is called a missense mutation) in the RAD51D gene. The study was focused on a French-Canadian population in which a specific missense change (c.620C>T) is particularly common. Findings showed that this change substantially raised the risk for high-grade serous ovarian cancer, which was seen in 3.8% of ovarian cancer patients and 0.2% of controls. Furthermore, laboratory studies showed that this gene change may confer sensitivity to PARP inhibitors. This is the first study to confirm a missense mutation in RAD51D and suggests that PARP-inhibitor therapies may be of use among this group of ovarian cancer patients.
Rivera et al. Cancer Res. 2017 Aug 15;77(16):4517-4529. PMID: 28646019.