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bioRxiv · 10.1101/066597

Genome Editing With Targeted Deaminases

Luhan Yang·Adrian Briggs·Wei Leong Chew·Prashant Mali·Marc Guell·John Aach·Daniel Goodman·David Cox·Yinan Kan·Emal Lesha·Venkataramanan Soundararajan·Feng Zhang·George Church
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Abstract

Precise genetic modifications are essential for biomedical research and gene therapy. Yet, traditional homology-directed genome editing is limited by the requirements for DNA cleavage, donor DNA template and the endogenous DNA break-repair machinery. Here we present programmable cytidine deaminases that enable site-specific cytidine to thymidine (C-to-T) genomic edits without the need for DNA cleavage. Our targeted deaminases are efficient and specific in Escherichia coli, converting a genomic C-to-T with 13% efficiency and 95% accuracy. Edited cells do not harbor unintended genomic abnormalities. These novel enzymes also function in human cells, leading to a site-specific C-to-T transition in 2.5% of cells with reduced toxicity compared with zinc-finger nucleases. Targeted deaminases therefore represent a platform for safer and effective genome editing in prokaryotes and eukaryotes, especially in systems where DSBs are toxic, such as human stem cells and repetitive elements targeting.

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Luhan Yang, Adrian Briggs, Wei Leong Chew, Prashant Mali, Marc Guell, John Aach, Daniel Goodman, David Cox, Yinan Kan, Emal Lesha, Venkataramanan Soundararajan, Feng Zhang, George Church. 2016-07-28. Genome Editing With Targeted Deaminases. https://doi.org/10.1101/066597

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