Construct: Amino acid replacement: S173A.
Female sex determining function: chromosomal XX tra- animals with one copy of the transgene have male-like intersexual phenotype, with a dominance of male structures but also definite female structures such as spermathecae and tergite 7. Male fertility function: females mated to tra- males with one copy of the transgene give rise to 79.1 +/- 10.6% fertilized eggs.