About the Authors
Department of Genetics, Stanford University School of Medicine, Stanford, California, United States of America
The authors have declared that no competing interests exist.
PJC, NDT, and RMM conceived and designed the experiments. PJC, YK, and LN performed the experiments. PJC analyzed the data. PJC, YK, LN, and NDT contributed reagents/materials/analysis tools. PJC and RMM wrote the paper. RMM supervised the laboratory and experimental results and edited the paper.