Since GLP-1 receptor agonists are successfully used to reduce body weight and improve insulin resistance in obese subjects, and bariatric surgery may influence GLP-1 levels [32], we recently started a clinical study on the effects of bariatric surgery on GLP-1 binding as measured with 68Ga-NODAGA-exendin-4 PET. The gene discussed is GCG; the disease is Insulin resistance.