A loxP site was inserted 139 bp upstream of exon 2 and an FRT-flanked PGK promoter-driven neopoly cassette and second loxP site were inserted downstream of exon 3. Cre-mediated recombination deleted exons 2 and 3 and the selection cassette. qPCR of anterior eye segments and inguinal fat pads confirmed absence of transcript in homozygotes. (J:307536)