The risk of local recurrence after excision and radiotherapy is similar in patients with BRCA1/2m BC and those with sporadic BC.2,6,94–96 Due to the ability of ionising radiation to induce DS breaks in DNA, and the involvement of BRCA1 and BRCA2 in repair of DS DNA, it has been suggested that BRCA1/2m-related tumours may be susceptible to the therapeutic and toxic effects of radiotherapy. The gene discussed is BRCA1; the disease is breast cancer.