Correction to: Nature Biotechnology, published online 18 November 2019.

In the version of this article initially published, the y-axis label in Fig. 1g read “Proportion of cells with active site(s) (%).” The correct label is “Proportion of cells with no active site(s) (%).” And, near the bottom of Fig. 4a, the probe for original variant (orange) was shown with a C nucleotide and the probe for edited base variants (red) was shown with T; these nucleotides were switched with each other. The errors have been corrected in the HTML and PDF versions of the article.