Treatment of patients with type 1 (T1D) and some type 2 (T2D) diabetes mellitus is based on insulin therapy in order to mimic the physiological pancreatic secretion according to a basal/bolus pattern obtained either by multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII) with an external insulin pump. This evidence concerns the gene INS and type 2 diabetes mellitus.