Nat. Biotechnol. 27, 309–311 (2009); published online 7 April 2009; corrected after print 8 July 2009

In the version of this article initially published, the incidence of gout was incorrectly stated to be in the hundreds of millions worldwide and 300 million in the US (p. 309, para. 2). The incidence is known for industrialized countries, not worldwide. In the US, the number is 3 million. The last five lines of the paragraph should have read, “including about 1 in 100 adult men in industrialized countries (an estimated 3 million in the US according to the Centers for Disease Control).” The errors have been corrected in the HTML and PDF versions of the article.