The transgene contains a 2.1kb sequence of human keratin 14 promoter upstream of the mouse baculoviral IAP repeat-containing 5 (Birc5) gene and a 2.2kb sequence of the human growth hormone and polyadenylation sequence. Transgene expression is specific to epidermal and follicular keratinocytes. Five founder mice were established and line 19 was chosen as the representative line.