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Cytosine base editor generates substantial off-target single-nucleotide variants in mouse embryos.

ABSTRACT: Genome editing holds promise for correcting pathogenic mutations. However, it is difficult to determine off-target effects of editing due to single-nucleotide polymorphism in individuals. Here we developed a method named GOTI (genome-wide off-target analysis by two-cell embryo injection) to detect off-target mutations by editing one blastomere of two-cell mouse embryos using either CRISPR-Cas9 or base editors. Comparison of the whole-genome sequences of progeny cells of edited and nonedited blastomeres at embryonic day 14.5 showed that off-target single-nucleotide variants (SNVs) were rare in embryos edited by CRISPR-Cas9 or adenine base editor, with a frequency close to the spontaneous mutation rate. By contrast, cytosine base editing induced SNVs at more than 20-fold higher frequencies, requiring a solution to address its fidelity.

SUBMITTER: Zuo E

PROVIDER: S-EPMC7301308 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Cytosine base editor generates substantial off-target single-nucleotide variants in mouse embryos.

Zuo Erwei E Zuo Erwei E Sun Yidi Y Wei Wu W Yuan Tanglong T Ying Wenqin W Sun Hao H Yuan Liyun L Steinmetz Lars M LM Li Yixue Y Yang Hui H Yang Hui H

Science (New York, N.Y.) 20190228 6437

Genome editing holds promise for correcting pathogenic mutations. However, it is difficult to determine off-target effects of editing due to single-nucleotide polymorphism in individuals. Here we developed a method named GOTI (genome-wide off-target analysis by two-cell embryo injection) to detect off-target mutations by editing one blastomere of two-cell mouse embryos using either CRISPR-Cas9 or base editors. Comparison of the whole-genome sequences of progeny cells of edited and nonedited blas ...[more]

PMID: 30819928

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