TCF7L2 and type 2 diabetes mellitus: The hub genes with the strong connections were KCNJ11, PPARG, ABCC8, THADA, WFS1, TCF7L2, and ADCY5. Interestingly, these genes are involved in the energy reserve metabolic process, glucose homeostasis, and negative regulation of pancreatic β cell apoptotic process, which revealed their potential functional impacts on the pathogenesis of T2D.