LOCALIZATION OF A GENE FOR DOMINANT CONE-ROD DYSTROPHY (CORD6) TO CHROMOSOME 17P

We have performed genetic linkage analysis on a four generation Britis h family with cone-rod dystrophy, Significant linkage to the disease g ene was obtained with eight marker loci situated on chromosome 17p12-p 13, A maximum two-point lod score of 5.93 with no recombination was ob tained with marker locus D17S1844. Critical recombinants identified wi th flanking marker loci placed the disease gene between D17S796/D17S93 8 and D17S954, an interval estimated to be 8 cM in size, This new loca lisation for autosomal dominant cone-rod dystrophy (CORD6) overlaps wi th regions attributed previously to Leber's congenital amaurosis, cent ral areolar choroidal dystrophy and dominant cone dystrophy, Given the ir differences in phenotype, the most plausible explanation would be t hat these different retinal disorders are caused by mutations in diffe rent genes mapping close together within the genome.