Imprecise excision of the P{bluetail} element, deleting sequences both proximal and distal to the site of the P{bluetail} insertion.
Homozygous males have no apparent tissue in A6.
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 AntpNs/+ antenna-to-leg transformation phenotype is exacerbated by Abd-BFab7-12 (which deletes the Fab-7 element) after a AntpNs Abd-BFab7-12 stock has been maintained for several generations; no difference in the AntpNs phenotype is seen immediately after the establishment of the AntpNs Abd-BFab7-12 stock, however, an exacerbation of the AntpNs phenotype emerges in subsequent generations of the stock, reaching a plateau after 3 to 5 generations.
Abd-BFab7-12 (which deletes the Fab-7 element) induces a significant increase in the number of sex comb teeth in the T1 leg in ScrW Scr4/+ males (mutations in cis).
The heterozygous gain of function phenotype is unchanged in a Polycomb group mutant background or a trxE2/+ background.