Gene Editing

Genome editing represents a group of newly developed capabilities that allow nucleotide-level targeting of genomic regions in a wide range of species. This chapter provides an overview of these technologies which open the possibility of creating directed mutations in virtually any location of the genome. Genome editing functions through the use of engineered endonucleases which create double-strand DNA breaks in the targeted genomic locus. DNA repair mechanisms, either nonhomologous end joining or homologous recombination, leave desired genetic modifications in targeted loci. Engineered genome editing allows knockout and knock-in experiments to be carried out in any species in which collection of one-cell embryos and their subsequent transfer is possible, eliminating the necessity of using embryonic stem cell intermediates. We introduce ZFN, TALEN, homing endonuclease, and Cas/CRISPR techniques together with a listing of resources and suppliers to assist in the design, construction, and carrying out of genome engineering experiments.