Analysis of 21 Stargardt's disease families confirms a major locus on chromosome 1p with evidence for non-allelic heterogeneity in a minority of cases.

Abstract

Autosomal recessive Stargardt's disease is a macular degeneration characterised by a juvenile onset and a rapidly progressive course resulting in an atrophic macular area typically surrounded by yellowish retinal flecks. The disease locus has previously been assigned to markers from chromosome 1p21-p13 by genetic linkage analysis in eight multiplex Stargardt's disease families. In an extended analysis, the assignment to chromosome 1p was confirmed in the majority of the 21 families with Stargardt's disease who were studied. In addition, a series of recombinant chromosomes further narrowed the Stargardt's disease region to an approximately 3 cM interval between markers at D1S424 and D1S497. Multipoint linkage analysis most probably excludes this locus in three of these families suggesting non-allelic heterogeneity with at least one additional minor Stargardt's disease locus.