Nat. Genet. 47, 312–319 (2015); published online 23 February 2015; corrected after print 29 August 2016

In the version of this article initially published, an affiliation for author Zsolt Fekete was incorrectly omitted. The missing affiliation was to the Department of Oncology, University of Medicine and Pharmacy Iuliu Hatieganu, Cluj-Napoca, Romania. The error has been corrected in the HTML and PDF versions of the article.