Nat. Biotechnol. 35, 833–844 (2017); published online 12 September 2017; corrected after print 12 September 2017

In the version of this article initially published, the Competing Financial Interests should have indicated the authors had competing interests, but instead indicated there were none. The detailed statement was missing from the HTML: J.T.S. receives research funding from Oxford Nanopore Technologies and has received travel and accommodations to speak at meetings hosted by Oxford Nanopore Technologies. N.J.L. has received honoraria to speak at Oxford Nanopore and Illumina meetings, and travel and accommodation to attend company-sponsored meetings. N.J.L. has ongoing research collaborations with Oxford Nanopore who have provided free-of-charge sequencing reagents as part of the MinION Access Programme and directly in support of research projects. In addition, the publication date was given as 11 September, rather than 12 September 2017. The errors have been corrected for the PDF and HTML versions of this article.