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Selict-seq profiles genome-wide off-target effects in adenosine base editing

ABSTRACT: Adenosine base editors (ABEs) facilitate the conversion of A•T base pairs to G•C base pairs, demonstrating significant potential for correcting pathogenic point mutations in humans. However, the off-target editing effects of ABEs remain inadequately characterized. In this study, we present a biochemical method, Selict-seq, designed to evaluate genome-wide off-target editing by ABEs. Selict-seq specifically captures dI-containing single-stranded DNA (ssDNA) and precisely identifies dA-to-dI mutation sites, thereby elucidating the off-target effects induced by ABEs. Through investigations involving three single-guide RNAs (sgRNAs), we identified numerous unexpected off-target edits both within and outside the protospacer regions. Analysis of these off-target sites revealed distinct characteristics of the ABE8e(V106W). These findings significantly advance our understanding of the off-target landscape associated with ABE8e. In summary, our approach enables an unbiased analysis of the ABE editome and provides a widely applicable tool for specificity evaluation of various emerging genome editing technologies.

ORGANISM(S): Homo sapiens

PROVIDER: GSE278492 | GEO | 2025/03/25

REPOSITORIES: GEO

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