The interior of the P-element present in the progenitor whd80k17 allele has been replaced by a (TA)23 microsatellite. Only 17bp of the P-element remain at each end.
Internal deletion of the P-element, 17bp remains at the 5' end and 17bp at the 3' end, 81 novel nucleotides are present at the deletion junction.
One of the "whd-F" group of alleles (P Fragment template). wA87.2 can be used as a template to convert the whd80k17 P-element sequences with its derivative wA87.2 sequence in the presence of transposase.