A cre/ERT2 cassette was inserted, along with an Frt flanked PGK-neomycin selection cassette, into the EcoRI site in exon 2 66 bp upstream of the translation initiation site. Heterozygous mice were later crossed with Tg(ACTFLPe)9205Dym mice to excise the neomycin selection cassette. (J:144088)