Mono- and bi-allelic mutations in the low-density lipoprotein receptor related protein 5 (LRP5) may cause osteopetrosis, autosomal dominant and recessive exudative vitreoretinopathy, juvenile osteoporosis, or persistent hyperplastic primary vitreous (PHPV). We report on a child affected with PHPV and carrying compound mutations. The father carried the splice mutation and suffered from severe bone fragility since childhood. The mother carried the missense mutation without any clinical manifestations. The genetic diagnosis of their child allowed for appropriate treatment in the father and for the detection of osteopenia in the mother. Mono- and bi-allelic mutations in LRP5 may cause osteopetrosis, autosomal dominant and recessive exudative vitreoretinopathy, juvenile osteoporosis, or PHPV. PHPV is a component of persistent fetal vasculature of the eye, characterized by highly variable expressivity and resulting in a wide spectrum of anterior and/or posterior congenital developmental defects, which may lead to blindness. We evaluated a family diagnosed with PHPV in their only child. The child presented photophobia during the first 3 weeks of life, followed by leukocoria at 2 months of age. Molecular resequencing of NDP, FZD4, and LRP5 was performed in the child and segregation of the observed mutations in the parents. At presentation, fundus examination of the child showed a retrolental mass in the right eye. Ultrasonography revealed retinal detachment in both eyes. Thorough familial analysis revealed that the father suffered from many fractures since childhood without specific fragility bone diagnosis, treatment, or management. The mother was asymptomatic. Molecular analysis in the proband identified two mutations: a c.[2091+2T>C] splice mutation and c.[1682C>T] missense mutation. We report the case of a child affected with PHPV and carrying compound heterozygous LRP5 mutations. This genetic diagnosis allowed the clinical diagnosis of the bone problem to be made in the father, resulting in better management of the family. It also enabled preventive treatment to be prescribed for the mother and accurate genetic counseling to be provided.

Background and Purpose: Transgenic mice over-expressing Notch2 in the uvea exhibit a hyperplastic ciliary body leading to increased IOP and glaucoma. The aim of this study was to investigate the possible presence of NOTCH2 variants in patients with primary open-angle glaucoma (POAG).Methods: We screened DNA samples from 130 patients with POAG for NOTCH2 variants by denaturing high-performance liquid chromatography after PCR amplification and validated our data by direct Sanger sequencing.Results: No mutations were observed in the coding regions of NOTCH2 or in the splice sites. 19 known SNPs (single nucleotide polymorphisms) were detected. An SNP located in intron 24, c. [4005 + 45A>G], was seen in 28.5% of the patients (37/130 patients). As this SNP is reported to have a minor allele frequency of 7% in the 1000 genomes database, it could be associated with POAG. However, we evaluated its frequency in an ethnic-matched control group of 96 subjects unaffected by POAG and observed a frequency of 29%, indicating that it was not related to POAG.Conclusion: NOTCH2 seemed to be a good candidate for POAG as it is expressed in the anterior segment in the human eye. However, mutational analysis did not show any causative mutation. This study also shows that proper ethnic-matched control groups are essential in association studies and that values given in databases are sometimes misleading.

Purpose: To report on the clinical and electrophysiological findings in a patient with oculo-auricular syndrome due to HMX1 mutation, with a follow-up of 12 years.Background: Oculo-auricular syndrome (MIM: 612109) is a rare developmental recessive condition affecting the eye and external ear that results from a mutation in the HMX1 gene. Previously described ocular abnormalities include bilateral microcornea, posterior synechiae, cataract, chorioretinal colobomas and rod–cone dystrophy.Methods: Retrospective chart review of an affected boy followed over a period of 12 years who had serial complete ophthalmologic examinations, fundus photographs, Goldmann perimetry and full-field electroretinograms (ERG).Results: Initial ERG tracings revealed generalized rod more than cone dysfunction. Thereafter, a rapid deterioration in rod and cone function was detected on follow up ERGs.Conclusion: The retinal degeneration in the recessively inherited oculo-auricular syndrome is a progressive rod-cone dystrophy. Visual prognosis is guarded considering the progressive nature of the retinal dystrophy in early infancy.

BACKGROUND/AIMS:Complement factor H (CFH) Y402H polymorphism shows a strong association with age-related macular degeneration (AMD). Although the phenotypic concordance of AMD has been shown in sibling/twin studies, little is known about the genotype-phenotype association. In this study, we investigated whether CFH Y402H is associated with early phenotypic features.METHODS:Statistical analysis was performed on 420 patients with AMD with complete clinical and genetic data (graded colour fundus photographs, according to the International Classification and Grading System for AMD and successful testing for CFH Y402H).RESULTS:In this Swiss population, an OR of 2.95 was confirmed for AMD in the presence of at least one risk C allele and OR of 9.05 for the CC homozygotes, corrected for age and sex. No difference was found between the AMD stages. Patients homozygous for the risk allele showed significant association with peripheral drusen (p = 0.028) and for central drusen location (p = 0.049). No trend was found for other drusen criteria (size, total surface, location nasal to disc) and for pigmentary changes.CONCLUSIONS:The CFH Y402H polymorphism showed a genotype-phenotype association for some drusen features. Additional genetic factors are likely to influence drusen phenotype.

La maladie de Stargardt est la plus fréquente des hérédo-dégénérescences maculaires et peut se manifester sous différentes formes cliniques. Il s'agit le plus souvent d'une transmission autosomique récessive par mutation du gène ABCA4 qui code pour une protéine ABCR. Nous rapportons le cas d'une famille tunisienne consanguine dont certains membres présentent des phénotypes Stargardt-like différents. L'atteinte semble être transmise sur le mode autosomique récessif. Une analyse génétique a été réalisée à la recherche d'une éventuelle corrélation génotype-phénotype. Cette étude a concerné deux familles nucléaires consanguines chez lesquelles nous avons retrouvé sept sujets atteints. Tous les membres ont bénéficié d'un examen ophtalmologique : acuité visuelle, champ visuel, fond d'œil, angiographie rétinienne à la fluorescéine et électrorétinogramme. Un génotypage a été réalisé utilisant les microsatellites D1S2813 et D1S2849 pour le gène ABCA4 et un autre marqueur intragénique. Une recherche des mutations déjà connues a été réalisée par micropuce du gène ABCA4 pour un patient et par séquençage ciblant huit exons pour les autres. Sur le plan clinique, trois phénotypes différents ont été individualisés : un phénotype de Stargardt avec maculopathie et silence choroïdien pour une patiente, un phénotype de Stargardt-fundus flavimaculatus pour quatre patients et un phénotype pouvant correspondre à un Stargardt évolué ou à une cone rod dystrophy avec une atrophie généralisée de la rétine pour deux patients. L'analyse génétique a démontré l'implication d'une mutation du gène ABCA4 dans l'apparition de la maladie et il existe chez les patients atteints trois individus recombinants. La mutation Arg 681Ter a été retrouvée à l'état hétérozygote dans une des branches familiales. Aucune des mutations connues du gène n'a été retrouvée chez les autres membres atteints de la famille. Ceci suggère la présence de mutations génétiques différentes au niveau du gène ABCA4. Dans le présent travail, nous rapportons une large généalogie présentant une dystrophie rétinienne liée au gène ABCA4. Bien que cette famille soit fortement consanguine et qu'une seule entité génétique semble être impliquée, elle présente une forte hétérogénéité phénotypique due probablement à une hétérogénéité mutationnelle.

The purpose of the present work was to generate, from retinal stem cells (RSCs), a large number of cells committed toward the photoreceptor fate in order to provide an unlimited cell source for neurogenesis and transplantation studies. We expanded RSCs (at least 34 passages) sharing characteristics of radial glial cells and primed the cells in vitro with fibroblast growth factor (FGF)-2 for 5 days, after which cells were treated with the B27 supplement to induce cell differentiation and maturation. Upon differentiation, cells expressed cell type-specific markers corresponding to neurons and glia. We show by immunocytochemistry analysis that a subpopulation of differentiated cells was committed to the photoreceptor lineage given that these cells expressed the photoreceptor proteins recoverin, peripherin, and rhodopsin in a same ratio. Furthermore, cells infected during the differentiation procedure with a lentiviral vector expressing green fluorescent protein (GFP) under the control of either the rhodopsin promoter or the interphotoreceptor retinoid-binding protein (IRBP) promoter, expressed GFP. FGF-2 priming increased neuronal differentiation while decreasing glia generation. Reverse transcription-polymerase chain reaction analyses revealed that the differentiated cells expressed photoreceptor-specific genes such as Crx, rhodopsin, peripherin, IRBP, and phosphodiesterase-alpha. Quantification of the differentiated cells showed a robust differentiation into the photoreceptor lineage: Approximately 25%-35% of the total cells harbored photoreceptor markers. The generation of a significant number of nondifferentiated RSCs as well as differentiated photoreceptors will enable researchers to determine via transplantation studies which cells are the most adequate to integrate a degenerating retina.

BACKGROUND:Malattia Leventinese (ML) is a genetically homogeneous macular dystrophy with an autosomal dominant mode of inheritance. Ophthalmoscopically it is recognisable by a radial pattern of drusen-like deposits in the macula and by parapapillary deposits, named Forni's verrucosities. The aim of this study is to describe optical coherence tomographic (OCT) findings and to compare them with histological data.PATIENTS AND METHODS:Six patients underwent ophthalmological examination, angiography and OCT. Diagnosis was confirmed by genetic analysis of the R345W mutation. A histopathological study of an ML donor eye was performed.RESULTS:OCT revealed a diffuse RPE-choriocapillaris thickening with nodular features in the macular and parapapillary areas. The protrusions reached as far as the outer nuclear layer.CONCLUSIONS:OCT is a non-invasive technique that provides a cross-sectional picture of the retina comparable to a histological section. In ML, OCT revealed a diffuse alteration of the RPE-Bruch's membrane complex. The macular and parapapillary nodular lesions are the tomographic equivalents of drusen and Forni's verrucosities.

AbstractBackground: Future treatment for genetic diseases may involve the replacement of malfunctioning genes through virus‐mediated gene therapy. However, this approach is plagued with many problems, both ethical and scientific. Therefore, alternative treatments based on new molecules may represent a safer option. Molecular treatment of many eye diseases will need to bring active molecules into the photoreceptors. Recently, the trans‐activator protein (TAT) human immunodeficiency virus type 1 (HIV‐1) transcriptional factor has proven to be effective in transporting molecules across cellular membranes. The half‐life of these molecules does not exceed 48 hours. The potential use of the retro‐inverso form of the TAT (D‐TAT) peptide, the protein transducing domain of the HIV‐1 transcriptional factor, as a molecular transporter was investigated.Methods: FITC‐labelled D‐TAT (D‐TAT FITC) was applied to the 661W murine photoreceptor cell line in culture. The labelled peptide was also injected into the vitreous body or the subretinal space of adult mice. Cells and cryosections of eyes were analysed under fluorescence microscopy at various time points after peptide treatment. Coimmunostaining with various antibodies was performed in order to characterize the transduces cells.Results: D‐TAT was effective in transducing photoreceptor cells in culture. Transduction of D‐TAT FITC was also effective when injected into the vitreous or subretinal space and was observed for a longer period of time than L‐TAT FITC.Conclusions: The retro‐inverso form of the TAT sequence is effective in transducing cells from various compartments of the eye. After 14 days, the D‐TAT FITC was clearly visible in the retina whereas L‐TAT FITC had almost disappeared. The D‐TAT peptide represents an interesting molecular transporter that, when coupled to a specific effector, may have potential therapeutic future, especially when a long‐lasting action is needed.

Background: Malattia Leventinese (ML) is a genetically homogeneous macular dystrophy with an autosomal dominant mode of inheritance. Ophthalmoscopically it is recognisable by a radial pattern of drusen-like deposits in the macula and by parapapillary deposits, named Forni's verrucosities. The aim of this study is to describe optical coherence tomographic (OCT) findings and to compare them with histological data. Patients and methods: Six patients underwent ophthalmological examination, angiography and OCT. Diagnosis was confirmed by genetic analysis of the R345W mutation. A histopathological study of an ML donor eye was performed. Results: OCT revealed a diffuse RPE-chorio-capillaris thickening with nodular features in the macular and parapapillary areas. The protrusions reached as far as the outer nuclear layer. Conclusions: OCT is a non-invasive technique that provides a cross-sectional picture of the retina comparable to a histological section. In ML, OCT revealed a diffuse alteration of the RPE-Bruch's membrane complex. The macular and parapapillary nodular lesions are the tomographic equivalents of drusen and Forni's verrucosities.