CFTR and cystic fibrosis: Mice harbouring CFTRtmc1UNC mutations were the first CF animal models generated for research use; however, inherent intestinal obstruction notoriously led to the premature demise of these mice; in response, bitransgenic mice expressing rat fatty acid binding protein 2 and an intestinal promotor for human CFTR (FABPhCFTR) were generated, extending survival to maturity [14].