Nat. Biotechnol. 29, 778–779 (2011); published online 8 September 2011; corrected after print 9 January 2012

In the version of this article initially published, Medco Health Solutions' location was given as Wilmington, Delaware; it should have been Franklin Lakes, New Jersey. On p. 779, in the first paragraph, left column, UBC is said to be HealthCore's parent company. In fact, Wellpoint is HealthCore's parent company. The errors have been corrected in the HTML and PDF versions of the article.