The class I da neurons of sna18 mutants show dorsal overextension of primary dendrites as well as a modest reduction in lateral branching.
94% of homozygous embryos hatch. Most homozygotes die as second instar larvae (although this may be due to other mutations on the wor1 chromosome). 100% of wor1/wor3 embryos hatch. 32% of wor1/wor3 animals survive to adulthood. 57% of wor1/wor4 embryos hatch. 38% of wor1/wor4 animals survive to adulthood. 21% of wor1/Df(2L)osp29 embryos hatch. None of these animals survive to adulthood. 10% of wor1/Df(2L)do1 embryos hatch. Homozygous second instar larvae have longer brainstems than control larvae and the morphology of the mutant brain hemisphere is less well-defined than that of controls. wor1/wor3 larvae have longer brainstems than control larvae.
Larval denticle belt polarity disrupted.