Miyuki Kawamura

Clinical features of Japanese families with a 402delT or a 555-556delAG mutation in choroideremia gene.

Purpose: To characterize the clinical features of two Japanese families with choroideremia associated with a 402delT and a 555–556delAG mutation in the choroideremia gene (CHM). Methods: Four affected members and one obligate carrier from two Japanese families with choroideremia were studied. To detect mutations of the CHM gene, the products of polymerase chain reaction were directly sequenced in both directions. The ophthalmologic examination included best-corrected visual acuity, slit-lamp examination, fundus examination, kinetic perimetry, electroretinography, and fluorescein angiography. Results: A 402delT and a 555–556delAG mutation were found in two Japanese families with choroideremia. All affected members had night-blindness, progressive constriction of the visual field, chorioretinal atrophy, and mottled appearance of the retinal pigment epithelium. The obligate carrier had mild patchy areas of retinal pigment epithelial atrophy with no visual symptoms. Conclusion: The authors found a 402delT and a 555–556delAG mutation in the CHM gene, one of which (402delT) is a novel mutation. They conclude that these mutations cause choroideremia in Japanese families.

Ocular findings in a Japanese family with an Arg41Trp mutation of the CRX gene

PurposeTo characterize the ophthalmological features and clinical course of an autosomal dominant cone–rod dystrophy (CORD2) in a Japanese family with an Arg41Trp mutation in the CRX gene.MethodsMutation screening by direct sequencing was performed on 42 patients with cone–rod dystrophy. The clinical features of the patients were characterized by the visual acuity and by the findings of slit-lamp biomicroscopy, electroretinography, fluorescein angiography, and kinetic visual field testing.ResultsAn Arg41Trp mutation in the CRX gene was identified in three members from three generations of one family with cone–rod dystrophy. Fundus examination demonstrated that the retinal dystrophy worsened with increasing age.ConclusionsA heterozygous Arg41Trp mutation in the CRX gene can produce cone–rod dystrophy in Japanese patients. Clinical examination of patients of different ages demonstrated that there was a rapid progressive worsening of the disease with increasing age.

Clinical Variabity of Patients Associated with RDH5 Gene Mutation

Fundus albipunctatus is a rare form of congenital stationary night blindness associated white dots in the fundus and extremely slow dark adaptation of the rod photoreceptors. In 1999, it was reported that the RDH5 gene which is localized on chromosome 12ql3-ql4 and encoded 11-cis retinol dehydrogenase, was a causative gene for fundus albipuncataus.1) In this study, we characterized the clinical features of Japanese patients associated with mutations in the RDH5 gene.