Impact of radiation quality on the spectrum of induced chromosome exchange aberrations

Abstract

Despite the reduced rejoining deficiency of DNA double-strand breaks induced by high-LET radiation, exposure to neutrons does not lead to enhanced levels of unrejoined chromosome breaks that can be observed as incomplete exchanges in cells that have reached mitosis. Proximity effects are more pronounced after densely ionizing radiation than after sparsely ionizing radiation. Clustered damage produced by neutron tracks results in a high proportion of complex aberrations and in non-reciprocal interactions of chromosome breaks. Most of the exchanges occur within one neutron track and little interaction seems to take place between the breaks formed in different tracks.