Germ cell migration occurs normally in mutant embryos and the germ cells are able to correctly associate with the gonadal mesoderm. However, the germ cells fail to form the tight cluster typically found in a properly coalesced gonad and instead remain loosely aligned. Mutants die at the end of embryogenesis, with no general defects in the nervous system, midgut, musculature or cuticle pattern.
Fas2-positive nerve bundles frequently cross the midline in mutant embryos, in contrast to wild-type.
Mutants exhibit failure of the ability of germ cells and the gonadal mesoderm to coalesce into the embryonic gonad. Very late stage embryos exhibit germ cells and somatic gonadal precursors (SGPs) remaining in a line, instead of the characteristic round shape of the gonads by stage 14. The SGPs appear as if they are incapable of making close contacts with one another.