Animal models for cystic fibrosis (CF) have contributed significantly to understanding of disease pathogenesis. In a recent study, Dr. Michelle V. Fanucchi, chair and associate professor in the department of environmental health sciences at the University of Alabama at Birmingham, along with colleagues, has described the development and characterization of the first cystic fibrosis rat, in which the cystic fibrosis transmembrane conductance regulator gene (CFTR) was knocked out using a pair of zinc finger endonucleases (ZFN).