Considering the fact that TFs such as PDX1, NEUROD1, HNF family proteins, play a crucial role in the development and differentiation of embryogenic pancreas and in the maintenance of functional mature islet cells (Table 1), the use of these key regulatory proteins in the establishment of insulin-producing β-cells from stem cells paved the way for radical treatment of insulin-dependent forms of diabetes mellitus (12, 13). This evidence concerns the gene INS and diabetes mellitus.