Mapping of autosomal dominant cone degeneration to chromosome 17p.

Purpose: We studied a single, large family with autosomal dominant cone degeneration in order to map the disease-causing gene.

Methods: Seventy-three individuals in this family were examined, and 34 were found to be affected. Blood samples from 34 affected and unaffected family members were obtained for DNA analysis and linkage mapping. Fifty-three genetic markers were analyzed in this family by using short tandem repeat markers. These markers were primarily in candidate genomic regions.

Results: Marker D17S796 generated a significantly positive LOD score of 4.21 (theta = .04; 10,000:1 odds in favor of linkage). Marker D17S513 gave a significant LOD score of 3.1 (theta = .096; 1,000:1 odds in favor of linkage). Other markers in the region generated suggestive findings, such as D17S786, with a LOD score of 2.7, and D17S945, with a LOD score of 2.41.

Conclusions: Our results indicate that a genetic defect that causes autosomal dominant cone degeneration is located on chromosome 17p in the region of recoverin. Recoverin, a retinal expressed gene, is an appealing candidate for this disease.