Many pharmacological attempts have been made to simulate the physiological effects of L-cell satiety hormone peptides GLP-1 and PYY as a treatment for obesity,1,5 and the findings presented in the current manuscript indicate that consideration of EEC-specific RGS may present new beneficial applications to therapeutic strategies in GPCR-based drug discovery for obesity. This evidence concerns the gene GCG and obesity due to melanocortin 4 receptor deficiency.