Nat. Biotechnol. 25, 1075–1077, 2007; published online 6 October 2007

In the version of this article initially published, it was incorrectly stated on p. 1076, paragraph 2, line four from bottom, that “Aya Jakobovits, originally at Cell Genesys and later at Abgenix, shepherded the XenoMouse through its entire development.” Five of the six XenoMouse strains developed at Abgenix were initiated after Jakobovits left in 1997.