Larvae expressing l(2)gl^GD4047 under the control of Scer\GAL4^en.PU in a minute background (RpL27A¹) live for about 11 days after egg laying and die with no signs of differentiation. The cells of the P-compartment of the wing disc appear highly disorganised due to loss of apical-basal polarity and increased hypoxia is seen compared to controls. At the extreme end of the larval stage these tumor cells are highly migratory, migrating towards the tracheal tubes and contacting their filopodia. The tumor cells also form new tracheal branches and can migrate along tracheal vessels and fuse with them. Tumor cells are seen to migrate from one disc to another, for example from the haltere disc, along a tracheal scaffold, to the wing disc.

Expression of bsk^DN.Scer\UAS suppresses the tumor growth seen when l(2)gl^GD4047 is expressed under the control of Scer\GAL4^en.PU in a minute background (RpL27A¹). Individuals differentiate into adult pharates and a small proportion of the pupae eclose into adults with no evident phenotypic alterations.

Dl¹ M(2)24F¹ double heterozygotes do not eclose, although many flies form pharate adults. These flies have many abnormalities, including shortening of the legs. The tarsus, which is primarily affected, is sometimes reduced to half the size of the tibia. The femur is bent like a bow. One pair of legs (usually the last pair) may be more affected than the others. The wings are often scalloped and have an extreme Dl mutant phenotype; showing both thickening at the crossveins and deltas at the wing margin. The texture of the wing is very brittle. The eye are very rough or may be reduced in size. The ocelli are sometimes fused or one of them may be missing. The bristles are larger than seen in the M(2)24F¹ single heterozygote and are often duplicated. Irregular additional hairs are seen on the thorax, as in Dl¹ single heterozygotes.