The pathogenesis of obesity and type-2 diabetes mellitus (T2D) overlaps with shared interlinked molecular pathways involving insulin resistance, oxidative stress and inflammatory procedures, often driven by dysregulated interactions with the glucagon-like peptide 1 (GLP-1) and GLP-1 receptors (GLP-1R) system [1,2,3]. The gene discussed is GCG; the disease is obesity due to melanocortin 4 receptor deficiency.