Easy quantitative assessment of genome editing by sequence trace decomposition

Abstract

The efficacy and the mutation spectrum of genome editing methods can vary substantially depending on the targeted sequence. A simple, quick assay to ac-curately characterize and quantify the induced mu-tations is therefore needed. Here we present TIDE, a method for this purpose that requires only a pair of PCR reactions and two standard capillary sequenc-ing runs. The sequence traces are then analyzed by a specially developed decomposition algorithm that identifies the major induced mutations in the pro-jected editing site and accurately determines their frequency in a cell population. This method is cost-effective and quick, and it provides much more de-tailed information than current enzyme-based as-says. An interactive web tool for automated decom-position of the sequence traces is available. TIDE greatly facilitates the testing and rational design of genome editing strategies