Type 1 diabetes is an autoimmune disease against pancreatic β cells whereas type two diabetes (T2D) is a multi-factorial disease due to two principal dysfunctions: (1) a loss of insulin secretion and (2) insulin resistance, which is defined by the failure of insulin to elicit anabolic effects and stimulate glucose uptake in targeted tissues. The gene discussed is INS; the disease is type 2 diabetes mellitus.