Genome Editing B.C. (Before CRISPR): Lasting Lessons from the "Old Testament"

Genome editing with engineered nucleases, a powerful tool for understanding biological function and revealing causality, was built in a joint effort by academia and industry in 1994-2010. Use of CRISPR-Cas9 is the most recent (2013-), and facile, implementation of the resulting editing toolbox. Principles and methods of genome editing from the pre-CRISPR era remain relevant and continue to be useful.