FlyBase curator comment: this entry is used to capture phenotypic information when the particular allele (or allele combination) used by the author could not be determined but the context of the experiment suggests that the phenotype being described is some kind of loss of function.
Egfrunspecified Pvrunspecified double mutant cells are generally located at the rear of the cluster during border cell posterior migration in mosaic border cell clusters consisting of both wild-type and mutant cells.