Large deletions induced in the white gene of Drosophila melanogaster by the antitumoral drug cis-dichlorodiammineplatinum(II): influence of non-homologous recombination.

We have studied two mutants carrying large deletions induced in the white gene of Drosophila by the antitumoral drug cisplatin. The breakpoints of the deletions were located by southern analysis and the sequences of the deletion junctions were determined. Two base-pair repeats are associated with the ends of these deletions; one of the repeats is preserved in the new junction after the deletion. DNA sequences such as A-T rich, alternating purine/pyrimidine tracts, polypurine-polypyrimidine tracts and topoisomerase I and II cleavage sites are found near the junctions. These results suggest that illegitimate recombinational processes are involved in the generation of cisplatin-induced large deletions.