The targeting vector, PRPGS00167_B-B10 obtained from the European Conditional Mouse Mutagenesis Program (EUCOMM) inserted a cassette composed of an FRT site followed by lacZ sequence and a loxP site into the first intron between exon 1 and 2. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site, and a second loxP site. A third loxP site is inserted in exon 4. The exons 2-3 and a part of exon 4 are thus flanked by loxP sites. A "conditional ready" (floxed) allele can be created by flp recombinase expression in mice carrying this allele. Subsequent cre expression results in a knockout mouse. If cre expression occurs without flp expression, a reporter knockout mouse will be created. (J:284679)