ix¹/ix² mutants do not have surviving doublesex-expressing larval terminal neuroblasts in the terminal region of the female third instar larval ventral nerve cord, similar to controls.

Diplo XX ix² homozygotes display variable degrees of intersexual characteristics, visible as incomplete and asymmetric development of the external terminalia and internal reproductive organs. The genital arch and anal plates are both affected, bristles are abnormal. Cell death is elevated in homozygous mutant genital discs.

Homozygous XX ix² flies are phenotypically intersexes, with simultaneous realisation of both male and female developmental pathways.

Diplo-X individuals carrying ix² display an intersex phenotype. Within the range of intersexual phenotypes in homozygotes or hemizygotes both the male and female type morphological features tend to be more robust at lower temperatures and in hemizygotes. Heterozygotes with ix⁴ are female fertile at 18^oC and display pronounced temperature-sensitive intersexuality at 25^oC or 29^oC.

Female flies lacking ix function have dorsal musculature appropriate to female flies, loss of ix function has no effect on the production of male specific muscle in males.

Homozygous XX flies are intersex.

Females homozygous for ix² have male-like pigmentation of posterior tergites, rudimentary ovaries and are sterile. Expression extreme and viability reduced at 27^oC; at 17^oC, expression less extreme and viability greater. Homozygous males appear normal but have nonmotile sperm. RK2. The possibility that the male sterility is at another locus has not been excluded.