CRB1 and retinitis pigmentosa: All participants had a formal diagnosis of an inherited retinal disease (n  =  3 Usher syndrome, n  =  1 CRB1-related retinitis pigmentosa, n  =  1 choroideremia, n  =  1 Stargardt disease) or a structural eye abnormality (n  =  1 microphthalmia).