BRCA1 and ovarian cancer: Poly(ADP‐ribose)‐polymerase (PARP) inhibitors (PARPis) have gained approval for treating homologous recombination (HR)‐defective ovarian cancers.[1] It has been reported that not only patients with BRCA1/2 mutations or HR deficiency[2] benefit from PARPi treatment, but also those with platinum‐sensitive ovarian cancers.[3] This benefit can be attributed to PARP1 trapping‐mediated cytotoxicity.[3] However, a significant proportion of ovarian cancer cases result in recurrence, distant metastases, and acquired PARPi resistance.