An FRT-flanked neomycin resistance cassette and a loxP-Stop-loxP-IRES-DTR (human diptheria toxin receptor)-mCherry element were introduced to exon 5, immediately after the stop codon. The mCherry is not expressed effectively after excision of the excision of the Stop element and mice should not be used as reporter animals. Flp-mediated recombination removed the FRT-flanked neo cassette. (J:230709)