Fig. (1) The scheme for the screen. Two days old Canton S wild
type males were starved for 12 hrs and then fed with vitamin C and
ZnCl2 in 1% sucrose solution for 12 hrs. These flies were allowed
to recover for ~4 hrs and then mated with attached XX virgin
females en masse for 2 days, transferred to new bottles and allowed
to lay eggs for another two days before discarding. The male
progeny were then examined for any mutations in the eye-color
gene white . A loss of function mutation in this gene should give
male progeny that have white eyes or mosaic patches of white
pigments in the eye.