About the Authors

Christopher J Johnson

Affiliations Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America , Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America

Joel A Pedersen

Affiliation Department of Soil Science and Molecular and Environmental Toxicology Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America

Rick J Chappell

Affiliation Biostatistics and Medical Informatics, University of Wisconsin Medical School, Madison, Wisconsin, United States of America

Debbie McKenzie

Affiliation Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America

Judd M Aiken

To whom correspondence should be addressed. E-mail: aiken@svm.vetmed.wisc.edu

Affiliations Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America , Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

CJJ, JAP, DM, and JMA conceived and designed the experiments. CJJ performed the experiments. CJJ and RJC performed the statistical analyses. JAP, RJC, and JMA contributed reagents/materials/analysis tools. CJJ, JAP, RJC, DM, and JMA analyzed the data and wrote the paper.