17 mutants with an ectopic posterior vulva-like structure, have been isolated and selected for further study. In the group I mutants, P8.p differentiates and forms the ectopic vulva-like structure in the posterior. In the group II mutants, a posterior invagination is formed by P7.p. P7.p fails to migrate towards P6.p, but nonetheless differentiates in these mutants. I mutants has shown that all 12 mutants are allelic to one another.
Molecular characterization is in progress.