Farrar et al. (1991) reported a large Irish family with late-onset autosomal dominant retinitis pigmentosa. The early stages of the disease were characterized by pigmentary deposits mainly in the inferior retinal midperiphery. There was loss of superior visual fields ...Farrar et al. (1991) reported a large Irish family with late-onset autosomal dominant retinitis pigmentosa. The early stages of the disease were characterized by pigmentary deposits mainly in the inferior retinal midperiphery. There was loss of superior visual fields initially with subsequent retraction of the visual fields. Reduced rod amplitudes with better preservation of cone amplitudes had been detected by ERG in affected individuals from 5 years of age. Night blindness occurred in the fourth decade with loss of peripheral visual fields. Rod and cone responses were lost by the fifth or sixth decade. Kikawa et al. (1994) identified a family with an autosomal dominant form of retinitis pigmentosa in which bull's-eye maculopathy was also present. The features were night blindness, usually noticed by the patient in the early teens; decreased visual acuity, with an onset in the late thirties; diffuse pigmentary retinal degeneration in the midperipheral to peripheral retina; and bull's-eye maculopathy, which also appeared in the late thirties. ERG assessments showed almost extinguished amplitudes of rod-isolated responses and severely reduced amplitudes of cone-isolated responses beginning at about age 9 years, even though the patient had no complaint of difficulty with night vision
In a large Irish family with late-onset autosomal dominant retinitis pigmentosa, Farrar et al. (1991) identified a 3-bp deletion in the RDS gene (179605.0001). Wells et al. (1993) identified the same mutation in another family with autosomal dominant retinitis ...In a large Irish family with late-onset autosomal dominant retinitis pigmentosa, Farrar et al. (1991) identified a 3-bp deletion in the RDS gene (179605.0001). Wells et al. (1993) identified the same mutation in another family with autosomal dominant retinitis pigmentosa. Kajiwara et al. (1994) demonstrated that retinitis pigmentosa-7 can be caused by digenic mutations (double heterozygosity): a leu185-to-pro mutation (179605.0004) in the RDS gene in combination with a null mutation of the ROM1 gene (180721.0001). Two-locus hypotheses have been proposed as the mechanism for a number of disorders; this is one of the first examples of molecular documentation