X-linked retinoschisis: Report of a family with a rare deletion in the XLRS1 gene

PURPOSE: To describe the clinical features and identify the disease causing mutation in a family with X-Iinked retinoschisis. DESIGN: Cohort study. METHODS: Genealogical investigation and mutation screening of the XLRS1 gene were performed in a four generation family of Icelandic ancestry. Three affected family members were evaluated clinically over a 29-year period. RESULTS: A rarely reported, four base pair deletion (375-378 del AGAT) in exon 5 of the XLRS1 gene was found in all affected males. A high degree of intrafamilial variability was observed in the progression of the disorder over 29 years. CONCLUSIONS: Identification of the disease causing mutation in this family allows for the diagnosis of individuals at risk for this inherited macular degeneration. Furthermore, the long-term follow-up of subjects with identical mutations helps to better characterize the highly variable clinical course of this disorder. (C) 2003 by Elsevier Inc. All rights reserved.