Eye pigment distribution: ventral. Dorsal half of the eye is unpigmented.
Introduction of z1 into homozygotes or heterozygotes enhances this phenotype so the unpigmented area extends into the ventral posterior region. Flies hemizygous or homozygous for z1 and homozygous for wAR4-24 are more severely repressed for w gene expression than are z+;wAR4-24 homozygotes and they maintain a small anterior ventral region of pigmented eye tissue.
Insertion has no effect on the normal X-linked copy of w+. The trans effects of wAR4-24, E1 and E2 on each other are proximity-dependent effects, possibly mediated by somatic chromosome pairing. R7 is a wild type trans-acting revertant on chromosome 3 and R8 is a partial trans-acting revertant on chromosome 3.