1. Department of Molecular Biology, University of Aarhus, Gustav Wieds Vej 10C, DK 8000 Aarhus C, Denmark, Department of Ophthalmology, Aarhus University Hospital, Nørrebrogade 44, DK 8000 Aarhus C, Denmark, and Departments of Pathology and Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710