Biological-derived or chemical drugs such as sulfonylureas, thiazolidinediones, biguanides, meglitinides, α-glucosidase inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors, glucagon-like peptide-1 (GLP1) receptor agonists, and dopamine D2-receptor agonists are currently the principal antidiabetic medications for diabetes mellitus (Blonde, 2009; Tahrani et al., 2011; He et al., 2019). The gene discussed is DPP4; the disease is diabetes mellitus.