PARP inhibitor efficacy may extend beyond those with germline BRCA1 or BRCA2 mutations to a wider group of patients, with up to 50% of high‐grade serous ovarian carcinoma (HGSOC) patients suspected of having tumour‐specific homologous recombination (HR) deficiency 7, 8. Here, BRCA2 is linked to ovarian serous carcinoma.