The aim of the present study was to investigate fasting and postprandial proinsulin and insulin responses, effects on glucose, free fatty acids (FFA) and triglycerides (TG) in previously morbidly obese subjects with GBP-induced weight loss, in comparison with subjects with morbid obesity (MO) and normal weight (NW) control subjects. The gene discussed is INS; the disease is morbid obesity.