Homozygous males raised at 20^oC have reduced viability (51% compared to wild-type) and a slight increase in the number of sex combs, usually having sex comb teeth on one or both second legs. Homozygous males raised at 24^oC have lower viability (43% compared to wild-type), always have sex comb teeth on both second legs, and usually have sex comb teeth on one or both third legs. Homozygous males raised at 27^oC do not survive to adulthood, but pharate adults have sex comb teeth on all legs. E(z)⁵/E(z)²⁸ males have lower viability and higher numbers of sex combs than E(z)²⁸ homozygotes at all temperatures. The fecundity of homozygous females drops during exposure to the restrictive temperature of 29^oC. Ovaries from females maintained at the restrictive temperature for 5 days have degenerating nurse cells in egg chambers beyond stage 3-4. The viability of eggs laid by females maintained at 29^oC drops to less than 10% within 1 day of the temperature shift.

Heat sensitive allele. Dominant suppressor of z mutants.