Nat. Med. 15, 1383–1391 (2009); published online 29 November 2009; corrected after print 4 February 2010

In the version of this article initially published, the official symbol for the gene encoding the aP2 protein was misidentified as Tcfap2a (the gene symbol for the transcription factor AP-2). The correct gene symbol is Fabp4. In no instances anywhere in the study was AP-2 examined. Additionally, Supplementary Figure 2a should also have been cited where Figure 2c was cited. The errors have been corrected in the HTML and PDF versions of the article.