Nat. Immunol. 11, 240–249 (2010); published online 14 February 2010; corrected after print 12 March 2010

In the version of this article initially published, references 35–41 were cited out of order in the text. The citations on page 247 should be as follows: column one, first paragraph, second full sentence, “RAG-2 recombinase protein35,36, which could in turn impair rearrangements37”; column two, middle paragraph, final two sentences, “iNKT development20,21,22,23,28,29,38,39....from stage 0 through stage 2 (refs. 20, 38)”; column two, final paragraph, second sentence, “RORγt-deficient thymocytes40”; and column two, final paragraph, fourth sentence, “Tcra rearrangements33,34,41.”

The error has been corrected in the HTML and PDF versions of the article.

The reference list should be as follows: