Deletion of the first 244 nucleotides from the 815bp HindIII-NdeI fragment of the orb 3' UTR.
9% of eggs produced by females carrying two copies of orbAN.Hsp83.T:Ecol\lacZ have ventralised chorions. 42.6% of eggs produced by orbF343/+ females carrying one copy of orbAN.Hsp83.T:Ecol\lacZ have ventralised chorions.