Cancer cells carrying BRCA mutations are especially sensitive to PARP inhibition.15, 16, 17 This phenomenon, known as synthetic lethality, results in cell death in response to PARP inhibition even in the absence of other insults.18, 19 The PARP inhibitor olaparib has been approved by the European Medicines Agency20 and the FDA21 in patients with BRCA‐mutated ovarian cancer. The gene discussed is PARP1; the disease is cancer.