These data suggest the hypothesis that, in addition to acceleration of gastric emptying, the optimal weight responders to the GLP-1 agonist class of drugs among patients with obesity may be those without markedly reduced satiety (i.e., those who are unable to ingest >2000 kcal in an ad libitum meal). The gene discussed is GCG; the disease is obesity due to melanocortin 4 receptor deficiency.