Homozygous diana1 mutants do not show any increased sensitivity to ethanol vapor compared with controls. However diana1 mutant flies do show reduced chronic tolerance to ethanol. Whereas control flies exhibit a reduced behavioural response following overnight pre-exposure to a low concentration of ethanol (never reaching intoxicating levels), a similar response in seen in diana1 mutant flies with or without pre-exposure. No change in rapid tolerance is seen; as in controls, the flies exhibit a reduced behavioural response 3.5 hours following pre-exposure to intoxicating levels of ethanol.
In memory tests, mutants perform at 86% of wild-type after a single training session, at 40% after spaced training.