A set of isogenic deficiency stocks created by FLP-induced recombination between FRT-carrying transgenic insertions; molecularly defined deletion endpoints correspond to initial location of the progenitor insertions. Initial set of 519 isogenic deletions provides 56% genome coverage.

The current Exelixis collection at the Bloomington Stock Center differs from the original described in FBrf0175003 : a significant number were shown not to carry a deletion and have been removed from the collection; a number of stocks have been lost; a number of additional deletions are included that were generated after publication.