Phenotypes in Defined Genotypes Including Siblings with Usher Syndrome.
Objective: To characterize visual function in defined genotypes including siblings with Usher syndrome. Methods: Thirteen patients with phenotypically different subtypes of Usher syndrome, including 3 families with affected siblings, were selected. Genetic analysis and ophthalmological examinations including visual fields, full-field electroretinography (ERG), multifocal electroretinography (mf ER