The PAI domain of eyg has been replaced by the PAI domain of ey.
eye | ectopic | ventral, with Scer\GAL4dpp.blk1
Expression of ey::eygEGGGGG.Scer\UAS, driven by Scer\GAL4dpp.blk1, does not induce ectopic eyes on appendages but, like overexpression of wild-type eyg, induces an extra ventral eye