Hnf1a (Tcf1) has been shown to activate the Glut2 gene in rat INS1 cells (Wang et al. 1999). It has been shown to bind the GLUT2 gene in mouse islets by chromatin immunoprecipitation, and decreased expression is observed in Hnf1a-/- islets (Parrizas et al, 2001). Glut2 expression in the developing pancreas in vivo is lost by embryonic day 18.5 in mice lacking a functional Hnf1a gene (Boj et al. 2001).