The transgene was designed with six copies of a T cell-specific transcription factor/lymphoid enhancer-binding factor 1 (TCF/Lef1) DNA binding site and a heat shock protein 1B (Hspa1b) minimal promoter driving expression of a cre/ERT2 fusion protein followed by a simian virus 40 (SV40) polyadenylation signal. Founder information and line numbers were not available. The pound symbol (#) is used when no line is specified and/or lines are pooled.