Nondisjunction induced by ethanol in Drosophila melanogaster females.
The effect of ethanol on chromosomal segregation was investigated in Drosophila melanogaster females homozygous for a structurally normal X chromosome marked with the recessive mutation yellow (y/y). For chronic treatments the females were kept from eclosion in food supplemented with 10% or 15% (v/v) ethanol, mated 24 or 48 h later to wild-type males and brooded in freshly prepared ethanol food. For the acute treatments 24- or 48-h-old females were exposed for 60 min to a 75% (v/v) ethanol solution by means of soaked tissue paper placed at the bottom of regular culture vials and brooded daily after mating. The results obtained show that: (1) both treatments significantly increased the frequency of X-chromosome nondisjunction; (2) after acute treatment this effect declined in later broods; (3) the yield of malformed flies in the progeny of acutely treated females was significantly higher than control values and also declined in later broods; (4) ovary analysis showed that chronic ethanol treatments caused a cessation of egg production. The induction pattern of nondisjunction and malformed flies is interpreted as giving support to the assumption that these effects may result from a direct action of ethanol. Ethanol toxicity was assessed by exposing females of different ages to a 50% or a 75% (v/v) solution for 60 min and counting the surviving flies 24 h later. The surviving fraction decreased steeply from 1-day-old (100%) to 5-day-old females (1.8%). It is suggested that toxicity may have been due to the action of a metabolite of ethanol, probably acetaldehyde.
Rey
M
M
Departamento de Radiobiología, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina.
Palermo
A M
AM
Muñoz
E R
ER
D000818:Animals; D004331:Drosophila melanogaster / Q000187:drug effects* / Q000235:genetics; D000431:Ethanol / Q000633:toxicity*; D005260:Female; D009152:Mutagenicity Tests; D009630:Nondisjunction, Genetic; D009865:Oocytes / Q000187:drug effects; D010053:Ovary / Q000187:drug effects; D014960:X Chromosome / Q000187:drug effects*
D000431:Ethanol