In adults, new therapeutic drugs already used in the treatment of Type 2 Diabetes (T2D) have been under experiment to obtain the best metabolic control in WS as, for example, Glucagon-Like Peptide-1 Receptor (GLP-1R) agonists (a peptide secreted from intestinal L cells after meals) [1,23,24,25] and exenatide (an incretin mimetic agent). The gene discussed is GCG; the disease is type 2 diabetes mellitus.