Electroretinogram (ERG) responses of flies containing homozygous clones in the eye are normal for 1 and 14 day old flies kept in constant darkness. However, if the flies are reared under 12 hour light/12 hour dark conditions, both the amplitude of the ERG and the size of the "on" and "off" transients become smaller with age. If the flies are kept under constant light conditions, the ERG amplitude is severely affected, showing a 90% reduction after only 5 days.
Homozygous follicle cell clones at the poles of the egg chamber are irregular in shape and pile up in multiple layers. In many cases, these multilayered regions comprise a mixture of mutant and wild-type cells. Homozygous follicle cell clones on the lateral sides of the egg chamber are indistinguishable from wild type.