EVALUATION OF THE GENOTOXICITY OF ANILINE-CENTER-DOT-HCL IN DROSOPHILA-MELANOGASTER

The induction of X-chromosome malsegregation, sex-linked recessive let hals and II-III autosomal translocations by aniline.HCl was investigat ed in Drosophila melanogaster. Nondisjunction was tested in 2 and id o ld virgin females fed on aniline.HCl solutions (3, 5, 10 and 15%) usin g a system where exceptional females (XXY) and only 1/4 of the expecte d regular progeny are viable. After mating, the females were subcultur ed daily. Similarly treated 7-day-old wild-type males were used to run classical II-III translocation and recessive lethal tests; for the la tter, the solutions were also injected intraabdominally. In all cases, five broods were obtained. A direct correlation was observed between concentration and toxicity. Furthermore, males were more sensitive tha n females, and the latter's sensitivity was higher at 4-day-old than a t 2-day-old. This could be attributed to a decrease with age in the ef ficiency of a detoxifying mechanism, or to the generation of a toxic m etabolite in older flies. Significant increases in nondisjunction were observed with 5, 10 and 15% solutions suggesting the existence of a t hreshold. No dose effect was detected within the range of the effectiv e concentrations used. The increases were observed in the first subcul ture (representing mostly stage 14 oocyte, i.e., cells in metaphase I) and in the third subculture. representing cells in which the spindle has not yet formed, thereby pointing to a direct effect of the chemica l on the chromosomes and not on the spindle. It is proposed that the s econd sensitivity peak detected might be the outcome of the transient loss of a protective configuration provided by the karyosome, due to i ts expansion in stages 9 and 10 of the developing oocytes. No sex-link ed lethals or translocations were induced. (C) 1998 Elsevier Science B .V.