Patients with T3cD need treatment for digestive problems, including replacement of pancreatic enzymes and the fat-soluble vitamins A, D, E, and K. Causal mechanisms of CF-related diabetes (CFRD) have long been thought to be β cell intrinsic, since it was granted that CF transmembrane conductance regulator (CFTR) was expressed in β cells (20). Here, CFTR is linked to cystic fibrosis-related diabetes.