title: The nature of radiation-induced mutations at the white locus of Drosophila melanogaster.
abstract: X-Ray- and neutron-induced mutations at the white locus of Drosophila melanogaster were used to study the nature of radiation-induced genetic damage. Genetic analysis showed the presence of multi-locus deficiencies in 15 out of 31 X-ray mutants and in 26 out of 35 mutants induced by neutrons. The DNA from 11 X-ray and 4 neutron mutants, which were not multi-locus deficiencies, was analyzed by Southern blot-hybridization. Deletions were observed in 2 X-ray and 1 neutron mutant. In combination with cytogenetic techniques, chromosomal rearrangements affecting the white locus (translocations, inversions, etc.) were identified in 3 X-ray and in 2 neutron mutants. A hot-spot for translocation breakpoints was identified in the left arm of the third chromosome. 5 X-ray mutants, which apparently did not contain large deletions, were subjected to further analysis by the nuclease S1 protection method, after cloning of the white gene. In 4 mutants a small deletion could indeed be detected in this way. Thus it seems that by far the main part of X-ray- and neutron-induced white mutants have arisen through large changes in the white gene, especially deletions.
mesh_terms: D000818:Animals; D002872:Chromosome Deletion; D004247:DNA / Q000032:analysis / Q000528:radiation effects; D004331:Drosophila melanogaster / Q000235:genetics* / Q000528:radiation effects; D005260:Female; D005796:Genes / Q000528:radiation effects*; D005804:Genes, Lethal; D005816:Genetic Complementation Test; D008297:Male; D009154:Mutation; D009502:Neutrons; D012150:Polymorphism, Restriction Fragment Length; D013094:Spermatozoa / Q000528:radiation effects; D014965:X-Rays
chemical_list: D004247:DNA