Hemizygous progeny derived from heterozygous females die during early larval stages. All embryos derived from homozygous germline clones die during embryonic development, and have very poorly differentiated cuticle which sometimes has holes in it. The head is defective, with abnormal spiracles, and the filzkorper material is very prominent. The CNS is very disorganised and the brain often protrudes dorsally rather than being covered by epidermis. The PNS is abnormal. Some embryos have a less extreme phenotype, with more cuticle differentiation and some defective denticle belt differentiation. The phenotype can be partially rescued by a paternal copy of wild-type sgg. Homozygous clones in the wing show homeotic transformation of hairs into bristles.