The prevalence of morbid obesity (BMI > 40 kg/m2) is increasing rapidly in the UK, but the investigators lack a coherent strategy for detailed assessment and treatment of the individuals affected, who are at high risk of morbidity and early mortality. The investigators already know that more than 1 in 20 severely-obese individuals have a simple genetic cause of their obesity (usually inherited in an autosomal dominant pattern. Bariatric surgery is the most effective treatment for morbid obesity and certain surgeries can result in the remission of type 2 diabetes. However, some patient fail to achieve the weight loss or experience complications and re-operations. The investigators are unable to predict the outcomes of bariatric surgery particularly in relation to type 2 diabetes remission which is crucial for the assessment of risk to benefit balance before wider future applications of the surgery.
The investigators want to investigate the mechanism underlying Type 2 diabetes remission after bariatric surgery by A) examining the effect of Mendelian forms of obesity and diabetes on T2D remission, B) studying changes in expression profiling patterns in insulin-responsive tissues, C) identifying of eQTLs, and of other genetic variations affecting T2D remission and D) studying the role of epigenetic variation in T2D remission.