About the Authors
Department of Genetics, Washington University School of Medicine, Saint Louis, Missouri, United States of America
Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
Department of Pediatrics, Children's Hospital, Boston, Massachusetts, United States of America
Howard Hughes Medical Institute, Boston, Massachusetts, United States of America
The authors have declared that no competing interests exist.
KAH and SLJ conceived and designed the experiments, analyzed the data, and wrote the paper. KAH performed the experiments. NB, LIZ, and SLJ contributed reagents/materials/analysis tools.