About the Authors

Dena M Johnson-Schlitz

Affiliation Department of Genetics, University of Wisconsin, Madison, Wisconsin, United States of America

Carlos Flores

Affiliation Department of Genetics, University of Wisconsin, Madison, Wisconsin, United States of America

William R Engels

To whom correspondence should be addressed. E-mail: wrengels@wisc.edu

Affiliation Department of Genetics, University of Wisconsin, Madison, Wisconsin, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

DMJS, CF, and WRE conceived and designed the experiments. DMJS and CF performed the experiments. WRE analyzed the data and wrote the paper.