Correction to: Nature Methods https://doi.org/10.1038/s41592-018-0014-2, published online 4 June 2018

The original version of this paper contained an incorrect primer sequence. In the Methods subsection “Rampage libraries,” the text for modification 3 stated that the reverse primer used for library indexing was 5′-CAAGCAGAAGACGGCATACGAGATXXXXXXXXGTGACTGGAGT-3′. The correct sequence of the oligonucleotide used is 5′-CAAGCAGAAGACGGCATACGAGATXXXXXXXXGTGACTGGAGTTCAGACGTGTGCTCTTCCGATCT-3′. This error has been corrected in the PDF and HTML versions of the paper.