TY - JOUR T1 - Enabling large-scale genome editing by reducing DNA nicking JF - bioRxiv DO - 10.1101/574020 SP - 574020 AU - Cory J. Smith AU - Oscar Castanon AU - Khaled Said AU - Verena Volf AU - Parastoo Khoshakhlagh AU - Amanda Hornick AU - Raphael Ferreira AU - Chun-Ting Wu AU - Marc Güell AU - Shilpa Garg AU - Hannu Myllykallio AU - George M. Church Y1 - 2019/01/01 UR - http://biorxiv.org/content/early/2019/04/04/574020.abstract N2 - To extend the frontier of genome editing and enable the radical redesign of mammalian genomes, we developed a set of dead-Cas9 base editor (dBE) variants that allow editing at tens of thousands of loci per cell by overcoming the cell death associated with DNA double-strand breaks (DSBs) and single-strand breaks (SSBs). We used a set of gRNAs targeting repetitive elements – ranging in target copy number from about 31 to 124,000 per cell. dBEs enabled survival after large-scale base editing, allowing targeted mutations at up to ~13,200 and ~2610 loci in 293T and human induced pluripotent stem cells (hiPSCs), respectively, three orders of magnitude greater than previously recorded. These dBEs can overcome current on-target mutation and toxicity barriers that prevent cell survival after large-scale genome engineering.One Sentence Summary Base editing with reduced DNA nicking allows for the simultaneous editing of >10,000 loci in human cells. ER -