Using bacterial recombineering technology, BAC RP24-68P2 containing the entire Krt19 was used to generate a transgene with a iCre-polyA cassette replacing the ATG codon and the following 632 bps of the coding sequence in the Krt19 gene. Twelve founder lines were generated. Line 2 and 5 heterozygous showed no health issue, and the line #2 was used for the studies. (J:279102)