Eye discs composed mainly of homozygous cells have a tumour phenotype.
Homozygous clones in mosaic eye discs do not survive well or persist through metamorphosis, but rather cause non-autonomous overgrowth of surrounding wild-type tissue.
Eye and wing discs composed predominantly of homozygous cells (generated using the FLP/cell-lethal method) are markedly overgrown. Larvae containing these discs become 'giant larvae' and die in pupation. The mutant tissue fails to undergo terminal differentiation and has defective epithelial organisation.