1. Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
2. Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
3. Shiley Eye Institute, University of California, San Diego, La Jolla, CA 92093, USA.
4. National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA.
5. Department of Computer Science, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
6. Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
7. Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
8. Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.