EFEMP1 is not associated with sporadic early onset drusen

The early onset of multiple drusen in the posterior pole of the retina is characteristic of a group of macular dystrophies often referred to as dominant or radial drusen. At least two forms, Doyne honeycomb retinal dystrophy (DHRD) and Malattia Leventinese (MLVT), are associated with a single missense mutation (R345W) in the gene encoding the EGF-containing fibulin-like extracellular matrix protein-1 (EFEMP1) and are now thought to represent a single entity. Here, we present a further evaluation of the role of EFEMP1 in the pathogenesis of sporadic forms of early onset drusen. We analyzed all coding exons of the EFEMP1 gene by SSCP analysis in 14 unrelated individuals with early onset of multiple drusen and no apparent family history of the disease. In this patient group, we did not detect the R345W mutation or any other disease-associated mutation. Three different polymorphisms and two intragenic polymorphic repeats were present in similar frequencies in the patients and control individuals. We conclude that EFEMP1 is unlikely to be involved in the disease in this patient group. This suggests that mutations in a different as yet unknown gene or genes may lead to the early onset drusen phenotype.