Genome editing with CRISPR–Cas nucleases, base editors, transposases and prime editors

Abstract

The development of new CRISPR–Cas genome editing tools continues to drive major advances in the life sciences. Four classes of CRISPR–Cas-derived genome editing agents—nucleases, base editors, transposases/recombinases and prime editors—are currently available for modifying genomes in experimental systems. Some of these agents have also moved rapidly into the clinic. Each tool comes with its own capabilities and limitations, and major efforts have broadened their editing capabilities, expanded their targeting scope and improved editing specificity. We analyze key considerations when choosing genome editing agents and identify opportunities for future improvements and applications in basic research and therapeutics.

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Fig. 1: Overview of genome editing strategies and agents.
Fig. 2: Genome editing with Cas nucleases.
Fig. 3: Installing transition point mutations with CRISPR–Cas base editors.
Fig. 4: CRISPR–Cas base editors and variants thereof.
Fig. 5: Decision trees for choosing base editors.
Fig. 6: Emerging CRISPR–Cas genome editing technologies: transposases and prime editors.

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Acknowledgements

This work was supported by the Merkin Institute of Transformative Technologies in Healthcare, US NIH grants U01AI142756, RM1HG009490, R01EB022376 and R35GM118062, and the HHMI. A.V.A. acknowledges a Jane Coffin Childs postdoctoral fellowship. L.W.K. acknowledges an NSF graduate fellowship.

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Correspondence to David R. Liu.

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Authors through the Broad Institute and Harvard University have filed patent applications on genome editing technologies, including base editing and prime editing. D.R.L. is a consultant and cofounder of Prime Medicine, Beam Therapeutics, Pairwise Plants and Editas Medicine, companies that use genome editing.

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Anzalone, A.V., Koblan, L.W. & Liu, D.R. Genome editing with CRISPR–Cas nucleases, base editors, transposases and prime editors. Nat Biotechnol (2020). https://doi.org/10.1038/s41587-020-0561-9

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