In studies using humans and animals, elevated circulating insulin and glucose of T2DM are associated with impaired insulin signaling in the brain that causes reduced trafficking of glucose transporters to neuronal membranes and changes in the insulin/phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway that negatively affect neuronal structure and function (11, 13–15). The gene discussed is INS; the disease is type 2 diabetes mellitus.