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bioRxiv · 10.1101/157925

Questioning unexpected CRISPR off-target mutations in vivo

Kim, S.-T.·Park, J.·Kim, D.·Kim, K.·Bae, S.·Schlesner, M.·Kim, J.-S.
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Abstract

To the Editor To the Editor References Recently, Schaefer et al.1 reported that whole genome sequencing (WGS) of two Cas9-treated, gene-corrected mice and a wild-type control mouse unveiled 1,397 single-nucleotide variations (SNVs) and 117 small insertions and deletions (indels) present commonly in the two Cas9-treated mice \"but absent in the uncorrected control\" and from a database of mouse SNVs and indels. There was essentially no sequence homology between the on-target site and these SNVs and indel sites, most of which lacked a protospacer-adjacent motif (PAM) sequence, suggesting that these variations were both small guide RNA (sgRNA)-independent and Cas9-independent, respectively. Nevertheless, the authors made a bold claim that these variations were caused by CRISPR-Cas9 without validating these unexpected off-target effects even at a single SNV or indel site by ...

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Kim, S.-T., Park, J., Kim, D., Kim, K., Bae, S., Schlesner, M., Kim, J.-S.. 2017-06-30. Questioning unexpected CRISPR off-target mutations in vivo. https://doi.org/10.1101/157925

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