A BAC derived 5.5 kb fragment of the Sprr2f promoter was cloned into a vector containing a cre coding sequence. Cre is expressed exclusively in endometrial epithelial cells and is naturally estrogen inducible due to the estrogen response elements in the Sprr2f regulatory region. The linearized construct was linearized and microinjected into FVB oocytes. Line 1 was assigned to this transgene in absence of specific line information. This transgene used different constructs compared to Tg(Sprr2f-cre)2Dcas generated by the same creator.