About the Authors
Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
The authors have declared that no competing interests exist.
Conceived and designed the experiments: EYX. Performed the experiments: CS MJWV VN YC TL NA YW EYX. Analyzed the data: CS MJWV NA EYX. Wrote the paper: EYX. Contributed to the manuscript revision: MJWV.