A search for some common characteristics of the effects of chemical mutagens in Drosophila

Transplacental genetic and cytogenetic effects of alkylating agents in the mouse. II. Induction of chromosomal aberrations

“…These data do not allow a clear-cut conclusion concerning the molecular damage responsible for induction of chromosomal aberrations as can be done for somatic cells and germ cells in Drosophilu. In this species, a preponderance of chromosomal changes is induced by chemicals with high s-values as compared to induced gene mutations [25,26]. Our results are parallel with the data found in CHO cells in which no direct association between clastogenic activity and the s-value has also been found [17].…”

The Drosophila wing test: A comparison of the sensitivity of different strains

“…ENU primarily causes O-ethylation, which is not thought to lead to chromosome breakage in Drosophila (Vogel, 1986). Indeed, ENU induces chromosome aberrations only at very high levels of ethylation in Drosophila germ cells and the primary lesion giving rise to aberrations is thought to result from N-alkylation (Vogel et al, 1982). In the w~°/w eye mosaic system Vogel et al (1982) found that alkylating agents such as MMS, efficient at producing chromosome aberrations in germ cells, yield high twin spot:single spot ratios whereas the opposite is true for ENU.…”

“…Indeed, ENU induces chromosome aberrations only at very high levels of ethylation in Drosophila germ cells and the primary lesion giving rise to aberrations is thought to result from N-alkylation (Vogel et al, 1982). In the w~°/w eye mosaic system Vogel et al (1982) found that alkylating agents such as MMS, efficient at producing chromosome aberrations in germ cells, yield high twin spot:single spot ratios whereas the opposite is true for ENU. In the wing system single spots always seem to predominate but it must be remembered that in the eye system the markers are allelic and thus single spots do not result, on the whole, from somatic recombination whereas in the wing assay recombination between mwh and fir 3 leads to single spots and between fir 3 and the centromere to twin spots.…”

“…The mutagens chosen for the study included the 2 alkylating agents methyl methanesulphonate (MMS) and ethyl nitrosourea (ENU). MMS preferentially alkylates base nitrogens, N-7 of guanine in particular, whereas over 80% of alkylations by ENU are on oxygen atoms (see Vogel et al, 1982). In addition, as we have a particular interest in the genetic effects of anti-cancer drugs, we included the anti-metabolites methotrexate (CAS No.…”