[The "2 + 1" mechanism as the basis for synergism in the neutron-photon irradiation of the spermatozoal genome in Drosophila melanogaster].

Cytogenetic analysis of polytene chromosomes of Drosophila melanogaster locus-specific mutants induced by consecutive neutron-photon irradiation has shown that their genome contains multiple intra- and inter-chromosome exchanges, including triradials, evidencing the synergistic action of such combined exposure. The appearance of the triradials may be only possible on the base of an interaction between a double and a single DNA strand breaks. The important significance of such interaction as the general mechanism for production of chromosome aberrations in irradiated cells of higher eucaryotes had been postulated by N. V. Luchnik as early as 10 years ago, but only nowadays it has been confirmed experimentally.