These disappointing findings may explain reluctance in some settings towards surgical treatment for patients with obesity and longer standing T2DM requiring insulin (T2DM-Ins): the national commissioning guidelines in Scotland, for example, permit referral for bariatric surgery only for patients with new-onset T2DM (less than 5 years) [19]. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.