Nat. Genet. 44, 619–622 (2012); published online 29 May 2012; corrected after print 9 July 2012

In the version of this article initially published, there were errors in the labeling of Figure 1b. Specifically, hyperdiploidy was mislabeled twice as hypodiploidy, and hypodiploidy was defined incorrectly as >44 instead of <44 chromosomes. These errors have been corrected in the HTML and PDF versions of the article.