In the December 2012 issue, the article entitled “Storm shows need for mouse backup, but costs present challenges” (Nat. Med. 18, 1724, 2012) incorrectly referred to the price of freezing per embryo as $1,000 to $4,000, when in fact this cost refers to the price of freezing per mouse line. The error has been corrected in the HTML and PDF versions of the article.

In the February 2013 issue, the article entitled “Amgen deal triggers watchful waiting in targeted nanomedicine” (Nat. Med. 19, 120, 2013 ) incorrectly referred to the drug docetaxel as decoxtel. The error has been corrected in the HTML and PDF versions of the article.