Nat. Med. 12, 1294–1300 (2006); published online 22 October 2006; corrected after print 10 May and 10 October 2007 and 18 July 2008

In the version of this article initially published, of the 122 samples assayed for sensitivity to daunorubicin for which the authors applied a predictor of adriamycin sensitivity, 27 samples were replicated owing to the fact that the same samples were included in several separate series files in the Gene Expression Omnibus generated in 2004 and 2005, which were the source of the data provided for the study. The authors have reanalyzed the prediction of adriamycin sensitivity using only the 95 unique samples and find a revised accuracy of 74%. Additionally, the authors have added two more accession numbers (GSE2351 and GSE649) to more clearly identify the sources of the samples. The errors have been corrected in the HTML and PDF versions of the article.