Type 2 diabetic patients withmarked hyperglycemia and on oral treatment should receive insulin prior to surgery.Insulin requirements may range from 0.25-0.40 U per gram of glucose in diabeticpatients with normal weight undergoing surgery to 0.4-0.8 U per gram of glucose indiabetic patients with obesity, liver disease, on treatment with steroids, orsepsis, and 0.8-1.2 U per gram of glucose in diabetic patients undergoing surgerywith use of extracorporeal circulation (ECC). The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.