Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom. Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. Department of Biomedical Sciences and the NNF Center for Basic Metabolic Research, The Panum Institute, University of Copenhagen, Copenhagen, Denmark. Department of Clinical Biochemistry, King's College Hospital NHS Foundation Trust, London, United Kingdom. Department of Surgery, St. George's University Hospitals NHS Trust, London, United Kingdom. Leadiant Biosciences, Amberley House, Windsor, Berkshire, United Kingdom. Department of Surgery and Cancer, Imperial College Healthcare NHS Trust, London, United Kingdom. Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, United Kingdom. Endocrinology, UCL Division of Medicine, Royal Free Hospital, London, United Kingdom.