The targeting vector contains a loxP site placed in intron 5 and an FRT::neomycin-delta thymidine kinase (Neo-DTK)::FRT::loxP cassette placed in intron 7. Flp-mediated recombination removed the FRT-flanked neomycin cassette. Cre-mediated recombination removed exons 6 and 7. The deletion creates a premature translation termination codon in exon 8 and deletes 80% of the coding region including the entire zinc finger DNA binding domain. (J:282446)