A loxP site was inserted upstream of exon 5. An FRT-flanked neomycin resistance cassette with a 5' loxP site was inserted downstream of exon 7. Flp-mediated recombination removed the neomycin resistance cassette. Cre-mediated recombination removed exons 5 through 7. Western blot analysis confirmed the absence of protein expression in E9.5 embryos and the retinal pigment epithelium. This allele was generated from Stra6tm2.1. (J:196841, J:203449)