The two incretin-based drugs, dipeptidyl peptidase-four inhibitor (DPP-4) and glucagon-like peptide-one (GLP-1RAs) agonists, along with sodium-glucose co-transporter (SGLT-2) inhibitors are novel classes of glucose-lowering drugs used in the management of T2DM. The gene discussed is DPP4; the disease is type 2 diabetes mellitus.