Open AccessOccurrence and Nature of Off-Target Modifications by CRISPR-Cas Genome Editing in Plants
Author(s) -
Mark H. J. Sturme,
Jan Pieter van der Berg,
Lex Bouwman,
Adinda De Schrijver,
Ruud A. de Maagd,
Gijs Kleter,
Evy Battaglia-de Wilde
Publication year - 2022
Publication title -
acs agricultural science and technology
Language(s) - English
Resource type - Journals
ISSN - 2692-1952
DOI - 10.1021/acsagscitech.1c00270
Subject(s) - crispr , genome editing , computational biology , genome , biology , computer science , genetics , gene
CRISPR-Cas-based genome editing allows for precise and targeted genetic modification of plants. Nevertheless, unintended off-target edits can arise that might confer risks when present in gene-edited food crops. Through an extensive literature review we gathered information on CRISPR-Cas off-target edits in plants. Most observed off-target changes were small insertions or deletions (1-22 bp) or nucleotide substitutions, and large deletions (>100 bp) were rare. One study detected the insertion of vector-derived DNA sequences, which is important considering the risk assessment of gene-edited plants. Off-target sites had few mismatches (1-3 nt) with the target sequence and were mainly located in protein-coding regions, often in target gene homologues. Off-targets edits were predominantly detected via biased analysis of predicted off-target sites instead of unbiased genome-wide analysis. CRISPR-Cas-edited plants showed lower off-target mutation frequencies than conventionally bred plants. This Review can aid discussions on the relevance of evaluating off-target modifications for risk assessment of CRISPR-Cas-edited plants.