The present invention provides genetically modified animals and cells comprising edited chromosomal sequences involved in ADME and toxicology. In particular, the animals or cells are generated using a zinc finger nuclease-mediated editing process. The invention also provides zinc finger nucleases that target chromosomal sequence involved in ADME and toxicology and the nucleic acids encoding said zinc finger nucleases. Also provided are methods of assessing the effects of agents in genetically modified animals and cells comprising edited chromosomal sequences involved in ADME and toxicology.
