Homozygous clones result in defects in both the socket and shaft structures of mutant sensory organs in the notum.

The lch5 neurons are situated in a more dorsal position than normal in 60-70% of abdominal segments in mutant embryos. The cell identities and cell numbers within the misplaced lch5 organs appear normal. When the lch5 dendrites point ventrally, the ligament cells are located in the most dorsal position within the organ as occurs in the thoracic dch3 organ. When the lch5 dendrites point posteriorly, the organs are stalled in the ventral part of the dorsal cluster and appear collapsed, with all the cells in approximately the same dorsoventral position. If the lch5 neurons are situated just below the dorsal bipolar dendrite (dbd) neuron, their dendrites point dorsoposteriorly. Once the lch5 organs are located below the level of the dbd neuron, the lch5 organs begin to assume their normal polarity and are rotated so that the ligament cells are most ventral and the dendrites point dorsally. The location of the attachment cells, adjacent to the dbd neuron, is not affected in the mutant embryos and the v'ch1 neuron is in its normal position. There is a marked decrease in the number of cells in the desC and desD organs compared to wild type, whereas des2 and desB seem largely unaffected. Many more apoptotic nuclei than normal are seen in the lateral clusters of the peripheral nervous system of mutant embryos. Mosaic animals in which most of the eye, head capsule, antennae and maxillary palps are homozygous for vvl^H599 (generated using the "eyFLP" system) have bristle defects on the mutant tissue, with almost all bristles on the mutant tissue being affected. On the head cuticle, the shafts are mainly shortened or distorted and splitting or duplication of shafts is also seen. Loss of the bristle shaft occurs less frequently. Many of the shafts are associated with 1-3 supernumerary sockets, appearing either as fused cells or as abnormally flat sockets. In almost all bristles with more than one socket, at least one shaft is present, indicating that the extra sockets are not formed at the expense of the shaft cells. In the eyes, bristles have dramatically shortened shafts, but the number of shaft and socket cells appear normal.

Defect in embryonic PNS development: abnormal position of LCh5 organs, possibly due to neuronal migration.