CFTR and cystic fibrosis: CF is a disease that results from a mutation of the CFTR gene, which leads to impaired ion transport and abnormally viscous secretions in the respiratory tract, intestines, pancreas, liver, and reproductive tract.17 These CF organoids, due to their histologic and genetic similarities with those of the parental tissue, were able to predict which drugs would work most effectively depending on the specific CFTR mutation the patient was harboring.16 The CF organoids have also allowed investigators to measure levels of CFTR functionality to develop patient‐specific therapies.