Prime editing with genuine Cas9 nickases minimizes unwanted indels

Abstract

Cas9 nickases (nCas9s) produce nicks or single-strand breaks in the DNA. Here the authors analyse the on- and off-target nicks generated by these nickases, and show that nCas9 (H840A) but not nCas9 (D10A) can cleave both strands and produce unwanted DNA double-strand breaks.