NORTH-CAROLINA MACULAR DYSTROPHY (MCDR1) - A REVIEW AND REFINED MAPPING TO 6Q14-Q16.2

The macular degenerations comprise a heterogeneous group of diseases, generally reported in small families. Single, large family studies of North Carolina macular dystrophy have aided in defining the spectrum o f the phenotype of this disorder and its relationship to other macular degenerations. North Carolina macular dystrophy has many phenotypic s imilarities to age-related macular degeneration with the glaring excep tion of the early age of onset of North Carolina macular dystrophy. Th e authors initially reported mapping this disease by linkage to the lo ng arm of chromosome 6. They now report additional data on a total of 247 individuals in the original North Carolina macular dystrophy famil y whom we ascertained for clinical and molecular genetic studies. Stan dard clinical ophthalmic examination revealed that 96 of these individ uals were affected. Molecular genetic studies increased the LOD score to 23 and refined the genomic localization of the disease-causing gene to 6q14-q16.2.