Nat. Biotechnol. 29, 121–128 (2011); published online 7 February 2011; corrected after print 12 April 2011 In the version of the article originally published, Table 1 left off AAV as a section heading. A number of products listed under Adenovirus should have been listed under AAV. Neurologix productNLXP10 was incorrectly listed under the heading of retrovirus, and in phase 2 of development.