Homozygous zol1 mutants show increased sensitivity to ethanol vapor compared with controls. zol1 mutant flies also show reduced ethanol tolerance. Whereas control flies exhibit a reduced behavioural response following pre-exposure to ethanol in comparison with humidified air, zol1 mutant flies exposed to either ethanol or air produce a similar response.
In memory tests, mutants perform at 101% of wild-type after a single training session, at 38% after spaced training.