Imprecise excision of the P{bluetail} element, deleting sequences both proximal and distal to the site of the P{bluetail} insertion.
Flies show a dominant Fab-7 gain of function phenotype indistinguishable from the Abd-BFab7-1 phenotype. Homozygotes show complete transformation of abdominal segment A6 to A7.
The heterozygous gain of function phenotype is unchanged in a Polycomb group mutant background.