Homozygous XX flies show a stronger phenotype than XY flies: XY flies look almost normal, but have slightly rounded analia, an incomplete penis apparatus and are sterile. dsx13/dsx1 XX flies have an intersex phenotype. XY dsx13/dsx12 males are fertile.
weak hypomorph; affects XX much more than XY; (XY; dsx12/dsx13 males fertile)