Aim: The Helping Evaluate Exenatide in overweight patients with diabetes compared with Long-Acting insulin (HEELA) study was designed to examine whether the glucagon-like peptide-1 (GLP-1) receptor agonist, exenatide, could improve HbA1c (≤7.4%) with minimal weight gain (≤1 kg) compared with insulin glargine. The gene discussed is GCG; the disease is diabetes mellitus.