Homozygous clones induced at the late blastoderm/early gastrulation stage and then examined in the third larval instar tracheal system show defects compared to wild-type clones; terminal cells show more extensive branching than wild-type terminal cells at similar positions.
Homozygous clones show defects in tracheal cell migration during morphogenesis of the dorsal air sac primordium; less than 40% of clones reach the distal tip of the primordium.