Mutations in the peripherin/RDS gene are an important cause of multifocal pattern dystrophy simulating STGD1/fundus flavimaculatus

Aim: To describe the phenotype and to analyse the peripherin/RDS gene in 10 unrelated families with multifocal pattern dystrophy simulating Stargardt disease (STGD1). Methods: The probands of 10 families and 20 affected family members underwent an ophthalmic examination including dilated fundus examination, fundus autofluorescence imaging and optical coherence tomography (OCT). In all probands and in selected family members, fluorescein angiography, electrophysiological testing and visual field analysis were performed. Blood samples were obtained from affected and unaffected family members for analysis of the peripherin/RDS gene. Results: All 10 probands carried mutations in the peripherin/RDS gene. Nine different mutations were identified, including six mutations that were not described previously. All probands showed a pattern dystrophy with yellow-white flecks in the posterior pole that strongly resembled the flecks seen in STGD1, on ophthalmoscopy as well as on autofluorescence and OCT. Clinical findings in the family members carrying the same mutation as the proband were highly variable, ranging from no visible abnormalities to retinitis pigmentosa. Conclusions: Mutations in the peripherin/RDS gene are the major cause of multifocal pattern dystrophy simulating STGD1/fundus flavimaculatus. This autosomal dominant disorder should be distinguished from autosomal recessive STGD1, in view of the different inheritance pattern and the overall better visual prognosis.