1. From the Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania; the
2. Division of Epidemiology and Clinical Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland; the
3. National Human Genome Research Institute, National Institutes of Health, Baltimore, Maryland; and the4Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
4. National Human Genome Research Institute, National Institutes of Health, Baltimore, Maryland; and the