[en] The authors compared DNA double-strand break (dsb) induction and rejoining, using field-inversion gel electrophoresis, with survival in mutant (XR-V15B) and wild-type parental (V79B) hamster cell lines after low dose neutron and X-irradiation. They found that neutrons do not appear to induce more dsbs than X-rays and deduce that increased sensitivity to neutrons is therefore not due to a higher initial yield of dsbs. They propose that neutron-induced dsbs have a higher probability of becoming lethal because they are more likely to be misrepaired during the slow stage of rejoining. (author)