Ovaries are devoid of egg chambers. Numbers and morphology of embryonic germ cells during stages when pole cells invaginate and form the embryonic gonads are no different to wild type. Larval ovaries are morphologically indistinguishable from wild type, gross aberrations have not yet occurred. By late pupae gonads fail to produce egg chambers and germ cells that are present fail to differentiate.
Chamberless ovaries. Transheterozygotes with otu13 produce ovaries containing predominantly tumorous egg cysts.
Spermatogenesis normal but mating behaviour fails because wild type females refuse to react to the courtship attempts of mutant males. Effect is not absolute, and depends on allele (there is a strong correlation between male sterility and severity of impairment in the female phenotype) and varies between affecting 6.7% (otu14) and 86.6% (otu12) of mutant males.
97% of homozygous ovarioles have quiescent oogonia.
Quiescent allele; homozygous and hemizygous ovarioles usually contain vitellaria that lack developing follicles, 8% or less of the oogonia are tumour-generating.
quiescent; ovarioles lack germ cells