They identified truncating XRCC2 mutations (11 different variants, five of these predicted to affect RAD51 domain) with the same frequency (0.07%) in 9 of 13,087 breast cancer cases and in 4 of 5488 controls from the UK (OR = 0.94, 95% CI 0.26–4.19), but a twofold-increased risk could not be excluded. The gene discussed is XRCC2; the disease is breast cancer.