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High-fidelity CRISPR–Cas9 nucleases with no detectable genome-wide off-target effects : Mutations on residues that bind to the phosphate backbone of the DNA can improve the specificity.
Cleavage
https://www.nature.com/articles/srep37584.pdf
Layman news:
https://www.wired.com/2017/06/crispr-mutations/
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