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Identification and classification of all retinitis pigmentosa (RP) causing mutations contribute to a better understanding of disease variants. In this report we describe a New Zealand family, of European heritage, affected by a sectoral type RP phenotype in association with a novel rhodopsin mutation (proline-170-histidine) in a highly conserved site.

Introduction: Sectoral retinitis pigmentosa (RP) is a rare clinical condition. Case Presentation:We present a 60-year-old femalewith a history ofmild night blindness and decreased vision in the left eye for about 15 years. Conclusions: Fundus examination revealed retinal pigmentary changes in the inferotemporal sector and reduced arterial caliber. In addition, fundus autofluorescence, fluorescein angiography,multifocal electroretinogramscans and electro-oculogramconfirmed these clinical findings. To the best of our knowledge, the present study is the first to describe sectorial RP in the inferotemporal sector of Iranian origin.

Purpose To report a Japanese patient with Oguchi disease and sectoral retinitis pigmentosa harboring a homozygous adenine deletion at position 1147 (1147delA) in the arrestin gene. Method Case report. Results In both eyes, golden discoloration with Mizuo-Nakamura phenomenon and tapetoretinal degeneration of the fundus were exhibited. Electroretinography showed abnormal a-wave and absent b-wave. The presence of 1147delA in the arrestin gene was demonstrated. Conclusions Our case provides further evidence of the close association of 1147delA in the arrestin gene in Japanese patients with Oguchi disease. Coexpression of both phenotypes of Oguchi disease and retinitis pigmentosa may suggest the possible involvement of additional defects of genes encoding the phototransduction proteins.

• A cytosine-to-adenine transversion in codon 23 of rhodopsin, the rod visual pigment gene, was reported recently by Dryja et al in 17 of 148 unrelated patients with autosomal dominant retinitis pigmentosa, but the clinical findings associated with this deletion have not been reported in detail. In screening our patients with autosomal dominant retinitis pigmentosa for the codon 23 transversion, we found positive results in four affected individuals from two families with sectoral retinitis pigmentosa, while 12 patients with sectoral retinitis pigmentosa from different families had negative results, suggesting that other gene sites or locations may give this same phenotypic change. From our patients' history of light exposure and the location of degeneration in the retina, we hypothesize that light phototoxicity may be playing an expressive role in this point mutation of the rhodopsin gene. This is the first report in which a type of retinitis pigmentosa has been associated with a specific molecular gene defect, although the actual pathophysiologic mechanism currently is unknown.

Protein synthesis, glycosylation, RNA synthesis, and neurotransmitter uptake were monitored using biochemical and autoradiographic techniques following in vitro labeling of retinal tissue from a 79-year-old female with sectoral retinitis pigmentosa (RP). Comparisons were made between degenerate and non-degenerate regions of the RP retina, and normal retinal tissues from an age- and postmortem-matched donor. Autoradiographs of non-degenerate retina from the RP eye following 3H-uridine incubation revealed virtually identical silver grain density over nuclei in all retinal strata as compared to normal control retinas. In contrast, a photoreceptor-specific reduction in silver grain density in the non-degenerate RP retina was noted following 3H-leucine incubation. In the normal retina, rod photoreceptor labeling with 3H-mannose was always greater than cone photoreceptor labeling. This pattern of incorporation was reversed in the non-degenerate region of the RP retina where rod photoreceptor labeling was less pronounced than that observed for cone photoreceptors. In non-degenerate regions of the RP retina, a marked accumulation of 3H-GABA by the Müller's cells was observed. Few cells exhibited selective uptake of 3H-muscimol, a GABA analog, indicating that few GABAergic neurons remained in the degenerate retina. 3H-dopamine-accumulating cell terminals were observed in the usual positions in the non-degenerate RP retina. In the degenerate region of the RP retina, heavy and diffuse uptake of 3H-GABA and 3H-muscimol, respectively, into broad cellular processes were noted, whereas 3H-dopamine was accumulated by only a few punctate terminals.