Affiliation: | Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK;, Department of Basic Veterinary Science, Department of Medical Genetics, Program in Molecular Medicine, Folkhälsan Research Institute, PO Box 63, University of Helsinki, Helsinki 00014, Finland;, Comparative Ophthalmology Unit, Animal Health Trust, Lanwades Park, Newmarket, Suffolk CB8 7UU, UK |