Autosomal dominant macular degeneration associated with 208delG mutation in the FSCN2 gene.

OBJECTIVE To assess the clinical and genetic characteristics of 2 Japanese families with autosomal dominant macular degeneration (ADMD) associated with a 208delG mutation in the retinal fascin (FSCN2) gene. DESIGN Case reports with clinical findings and results of fluorescein angiography, electroretinography, kinetic visual field testing, and DNA analysis. SETTING University medical center. RESULTS The 208delG mutation in the FSCN2 gene was identified in 14 members of 4 Japanese families with autosomal dominant retinitis pigmentosa and in 5 members of 2 Japanese families with ADMD. The characteristic features associated with this mutation led to 2 different phenotypes, autosomal dominant retinitis pigmentosa and ADMD. CONCLUSIONS The 208delG mutation in the FSCN2 gene produces not only autosomal dominant retinitis pigmentosa but also ADMD in the Japanese population. This mutation is relatively common in Japanese patients with autosomal dominant retinal degeneration and showed clinical variability. CLINICAL RELEVANCE Autosomal dominant retinitis pigmentosa and ADMD can be caused by the same 208delG mutation. We suggest that mutations in the FSCN2 gene can lead to a spectrum of phenotypes.