HNF1B and type 2 diabetes mellitus: For example, PDX1 directs the early embryonic development of pancreas and differentiation of insulin-producing islet β cells in endocrine pancreas by forming cross-regulatory transcriptional networks where FOXA2 and HNF1B, other T2D associated genes are also key players (Oliver-Krasinski et al., 2009; Arda et al., 2013).