A GENE FOR AUTOSOMAL-DOMINANT PROGRESSIVE CONE DYSTROPHY (CORD5) MAPSTO CHROMOSOME 17P12-P13

Inherited retinal dystrophy is a common cause of visual impairment. Co ne dystrophy affects the cone function and is manifested as progressiv e loss of the central vision, defective color vision, and photophobia. Linkage was demonstrated between progressive cone dystrophy (CORD5) a nd genetic markers on chromosome 17p12-p13 in a five-generation family . Multipoint analysis gave a maximum lod score of 7.72 at the marker D 17S938. Recombinant haplotypes in the family suggest that the cone dys trophy locus is located in a 25-cM interval between the markers D17S92 6/D17S849 and D17S804/D17S945. Furthermore, one recombination was dete cted between the disease locus and a microsatellite marker in the cand idate gene RCV1, encoding the retinal protein recoverin. Two additiona l candidate genes encoding retinal guanylate cyclase (GUC2D) and pigme nt epithelium-derived factor (PEDF) are located at 17p13.1. Moreover, loci for retinitis pigmentosa and Leber congenital amaurosis have been mapped to the same region. Identification of the cone dystrophy locus may be of importance not only for identifying functional genes in the cone system, but also for identifying genes for other retinal disorde rs. (C) 1995 Academic Press, Inc.