Vol. 214, No. 10, October 2017. https://doi.org/10.1084/jem.20171093

The authors regret that in the original version of their paper, Eric Tycksen was inadvertently omitted from the author list. The corrected author list appears above. E. Tycksen’s affiliation is Genome Technology Access Center, Department of Genetics, Washington University in St. Louis, St. Louis, MO.

All versions of this article have been corrected.