LOCALIZATION OF AN AUTOSOMAL-DOMINANT RETINITIS-PIGMENTOSA GENE TO CHROMOSOME-7Q

Retinitis pigmentosa is a group of clinically and genetically heteroge neous retinopathies and a significant cause of worldwide visual handic ap. We have typed DNA from members of a Spanish family segregating an autosomal dominant form of retinitis pigmentosa (adRP) using a large s eries of simple sequence polymorphic markers. Positive two-point lod s cores have been obtained with fifteen markers including D7S480 (theta( max)=0.00, Z(max)=7.22). Multipoint analyses using a subset of these m arkers gave a lod score of 7.51 maximizing at D7S480. These data provi de definitive evidence for the localisation of an adRP gene on chromso me 7q, and highlight the extensive genetic heterogeneity that exists i n the autosomal dominant form of this disease.