Subcutaneously injectable GLP-1 receptor (GLP-1R) agonists (DPP-4 mediated degradation-resistant peptides with improved pharmacokinetics that act via the human GLP-1R) and oral DPP-4 inhibitors (small molecules with clinically useful oral bioavailability that shield the endogenous peptide from DPP-4 metabolism and thereby enhance its innate insulinotropic activity) are now licensed and have become part of the standard of care for the management of T2DM [17-19]. This evidence concerns the gene GLP1R and type 2 diabetes mellitus.