TY - JOUR T1 - Direct profiling of genome-wide dCas9 and Cas9 specificity using ssDNA mapping (CasKAS) JF - bioRxiv DO - 10.1101/2021.04.16.440202 SP - 2021.04.16.440202 AU - Georgi K. Marinov AU - Samuel H. Kim AU - S. Tansu Bagdatli AU - Alexandro E. Trevino AU - Josh Tycko AU - Tong Wu AU - Lacramioara Bintu AU - Michael C. Bassik AU - Chuan He AU - Anshul Kundaje AU - William J. Greenleaf Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/04/17/2021.04.16.440202.abstract N2 - Detecting and mitigating off-target activity is critical to the practical application of CRISPR-mediated genome and epigenome editing. While numerous methods have been developed to map Cas9 binding specificity genome-wide, they are generally time-consuming and/or expensive, and not applicable to catalytically dead CRISPR enzymes. We have developed a rapid, inexpensive, and facile assay for identifying off-target CRISPR enzyme binding and cleavage by chemically mapping the unwound single-stranded DNA structures formed upon binding of a sgRNA-loaded Cas9 protein (“CasKAS”). We demonstrate this method in both in vitro and in vivo contexts.Competing Interest StatementG.K.M., W.J.G, T.W. and C.H. have submitted a provisional patent application based on this work. ER -