Imprecise excision of the progenitor insertion, resulting in a deletion that removes part of the Sans gene and also affects the CG30487 gene (gene on opposite strand within an intron of Sans). The deletion is of 1331bp, spanning from nucleotide 122367 to nucleotide 123696 of the genomic sequence AE003820.

The morphology of follicle cell microvilli in homozygous females is indistinguishable from that of wild type.