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bioRxiv · 10.1101/2020.03.27.012104

Detection of deleterious on-target effects after HDR-mediated CRISPR editing

Weisheit, I.·Kroeger, J. A.·Malik, R.·Klimmt, J.·Crusius, D.·Dannert, A.·Dichgans, M.·Paquet, D.
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Abstract

CRISPR genome editing is a promising tool for translational research but can cause undesired editing outcomes, both on-target at the edited locus and off-target at other genomic loci. We investigated the occurrence of deleterious on-target effects in human stem cells after insertion of disease-related mutations by homology-directed repair (HDR). We identified large, mono-allelic genomic deletions and loss-of-heterozygosity that escaped standard quality controls in up to 40% of edited clones. To reliably detect such events, we developed simple, low-cost and universally applicable quantitative genotyping PCR (qgPCR) as well as sequencing-based tools and suggest their usage as additional quality controls after editing. This will help to ensure the integrity of edited loci and increase the reliability of CRISPR editing.

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Weisheit, I., Kroeger, J. A., Malik, R., Klimmt, J., Crusius, D., Dannert, A., Dichgans, M., Paquet, D.. 2020-03-29. Detection of deleterious on-target effects after HDR-mediated CRISPR editing. https://doi.org/10.1101/2020.03.27.012104

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