Best's disease is an autosomal dominant disorder with incomplete penetrance and variable expression. A typical characteristic of Best's disease is a pathological EOG. We describe four members of a family with bilateral, subfoveal vitelliform lesions. The EOG was normal in all cases. Genetic analysis of the oldest son indicated a heterozygotic mutation Ala234Val in the VMD2 gene, so-called bestrophin gene, which is associated with Best's disease. Molecular genetic analysis also found Best's disease with a normal EOG. A normal EOG cannot exclude Best's disease. The family members should receive genetic consultation and if wished analysis of the VMD2 gene.