RNA Therapeutics Institute Publications


Partial DNA-guided Cas9 enables genome editing with reduced off-target activity

UMMS Affiliation

Department of Molecular, Cell and Cancer Biology; Program in Molecular Medicine; Department of Biochemistry and Molecular Pharmacology

Publication Date


Document Type



Biochemistry, Biophysics, and Structural Biology | Cell and Developmental Biology | Genetics and Genomics | Therapeutics


CRISPR-Cas9 is a versatile RNA-guided genome editing tool. Here we demonstrate that partial replacement of RNA nucleotides with DNA nucleotides in CRISPR RNA (crRNA) enables efficient gene editing in human cells. This strategy of partial DNA replacement retains on-target activity when used with both crRNA and sgRNA, as well as with multiple guide sequences. Partial DNA replacement also works for crRNA of Cpf1, another CRISPR system. We find that partial DNA replacement in the guide sequence significantly reduces off-target genome editing through focused analysis of off-target cleavage, measurement of mismatch tolerance and genome-wide profiling of off-target sites. Using the structure of the Cas9-sgRNA complex as a guide, the majority of the 3' end of crRNA can be replaced with DNA nucleotide, and the 5 - and 3'-DNA-replaced crRNA enables efficient genome editing. Cas9 guided by a DNA-RNA chimera may provide a generalized strategy to reduce both the cost and the off-target genome editing in human cells.

DOI of Published Version



Nat Chem Biol. 2018 Mar;14(3):311-316. doi: 10.1038/nchembio.2559. Epub 2018 Jan 29. Link to article on publisher's site

Journal/Book/Conference Title

Nature chemical biology

Related Resources

Link to Article in PubMed

PubMed ID