The 196 kb C57BL/6J mouse bacterial artificial chromosome (BAC) RP23-405B24, containing the entire Scnn1a locus (and other genes), was modified by targeting a Cre recombinase coding sequence (the CreERT2 sequence modified back to encode the normal Cre recombinase gene), SV40 polyA signal, and frt-flanked neomycin cassette to the ATG start site of the Scnn1a locus. The targeted BAC sequences were further modified using FLP recombination to remove the selection cassette and linearized to remove its original vector backbone. The resulting modified BAC was microinjected into embryos from B6C3 mice ((C57BL/6 x C3H)F1 x C57BL/6). Transgenic males from founder line Scnn1a-Tg3-Cre was bred to C57BL/6J females to generate the colony.