Erratum for vol. 101, p. 2963

In the article by Manno et al entitled “AAV-mediated factor IX gene transfer to skeletal muscle in patients with severe hemophilia B,” which appeared in the April 15, 2003, issue of Blood (Volume 101:2963-2972), the second sentence of “Safety studies” should have read “Vector sequences were detected in the urine of subjects B and F up to 24 hours after injection but not thereafter.”