HNF1B and Menkes disease: Genes associated with MD are not only expressed in pancreatic islet cells but also mutations in TFs that govern pancreatic development, such as PDX1, NGN3, PTF1A, NEUROD1, RFX6, NKX2.2, MNX1, GLIS3, GATA4, GATA6, HNF1B lead to permanent ND (PNDM).5 Homozygous mutations in GATA4, GATA6, PDX1, and PTF1A cause agenesis of the pancreas, whereas mutations in WSF1, EIF2AK3, IER3IP, and FOXP lead to syndromic MD.5 Furthermore, mutations in proteins related to glucose metabolism including GCK (Glucokinase) and GLUT2 (SLC2A2) also lead to PNDM.