Tg(Wap-TAg)12Gmn

The transgene consists of a 1600 bp DNA fragment containing the promoter of the mouse whey acidic protein gene joined to the SV40 early region, which includes the overlapping sequences encoding the SV40 large and small T-antigen genes. So that only the large T antigen is expressed, the 5' splice site of the small t antigen mRNA was modified by site directed mutagenesis (AAG/GTAAAT to AAG/CGCAAT) to prevent splicing of the small t transcript. (J:56330, J:69711)