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Hassan S, Hsu Y, Thompson JM, Kalmanek E, VandeLune JA, Stanley S, Drack AV. The dose-response relationship of subretinal gene therapy with rAAV2tYF-CB-h RS1 in a mouse model of X-linked retinoschisis. Front Med (Lausanne) 2024; 11:1304819. [PMID: 38414621 PMCID: PMC10898246 DOI: 10.3389/fmed.2024.1304819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Accepted: 01/16/2024] [Indexed: 02/29/2024] Open
Abstract
Purpose X-linked retinoschisis (XLRS), due to loss-of-function mutations in the retinoschisin (RS1) gene, is characterized by a modest to severe decrease in visual acuity. Clinical trials for XLRS utilizing intravitreal (IVT) gene therapy showed ocular inflammation. We conducted a subretinal dose-response preclinical study using rAAV2tYF-CB-hRS1 utilizing the Rs1 knockout (Rs1-KO) mouse to investigate short- and long-term retinal rescue after subretinal gene delivery. Methods Rs1-KO mice were subretinally injected with 2 μL of rAAV2tYF-CB-hRS1 vector with 8E9 viral genomes (vg)/eye, 8E8 vg/eye, 8E7 vg/eye, or sham injection, and compared to untreated eyes. Reconstitution of human RS1 protein was detected using western blotting. Analysis of retinal function by electroretinography (ERG) and structural analysis by optical coherence tomography (OCT) were performed at 1, 2, 3, 5, 7, and 12 months post injection (MPI). Immunohistochemistry (IHC) was performed to evaluate cone rescue on the cellular level. Functional vision was evaluated using a visually guided swim assay (VGSA). Results Western blotting analysis showed human RS1 protein expression in a dose-dependent manner. Quantification of western blotting showed that the RS1 protein expression in mice treated with the 8E8 vg dose was near the wild-type (WT) expression levels. ERG demonstrated dose-dependent effects: At 1 MPI the 8E8 vg dose treated eyes had higher light-adapted (LA) ERG amplitudes in 3.0 flash and 5 Hz flicker compared to untreated (p < 0.0001) and sham-treated eyes (p < 0.0001) which persisted until the 12 MPI endpoint, consistent with improved cone function. ERG b-wave amplitudes were higher in response to dark-adapted (DA) 0.01 dim flash and 3.0 standard combined response (SCR) compared to sham-treated (p < 0.01) and untreated eyes (p < 0.001) which persisted until 3 MPI, suggesting short-term improvement of the rod photoreceptors. All injections, including sham-treated, resulted in a cyst severity score of 1 (no cavities), with significant reductions compared to untreated eyes up to 3 MPI (p < 0.05). The high and low dose groups showed inconsistent ERG improvements, despite reduced cyst severity, emphasizing the dose-dependent nature of gene augmentation's efficacy and the tenuous connection between cyst reduction and ERG improvement. IHC data showed a significant cone rescue in eyes treated with the 8E8 vg dose compared to sham-treated and untreated eyes. VGSA showed better functional vision in 8E8 vg dose treated mice. Eyes treated with the highest dose showed occasional localized degeneration in the outer nuclear layer. Conclusion Our data suggest that a dose of 8E8 vg/eye subretinally improves retinal function and structure in the Rs1-KO mouse. It improves cone function, rod function, and reduces cyst severity. Sham treatment resolves schisis cysts, but 8E8 vg/eye is needed for optimal retinal electrical function rescue. These findings offer a promising path for clinical translation to human trials.
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Affiliation(s)
- Salma Hassan
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
- Biomedical Science-Cell and Developmental Biology Graduate Program, Department of Anatomy and Cell Biology, University of Iowa, Iowa City, IA, United States
| | - Ying Hsu
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Jacob M Thompson
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA, United States
| | - Emily Kalmanek
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Joel A VandeLune
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Sarah Stanley
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
| | - Arlene V Drack
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, and Carver College of Medicine, University of Iowa, Iowa City, IA, United States
- Biomedical Science-Cell and Developmental Biology Graduate Program, Department of Anatomy and Cell Biology, University of Iowa, Iowa City, IA, United States
- Department of Pediatrics, University of Iowa, Iowa City, IA, United States
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Liu Z, Guo J, Pan M, Xie K, Du L, Jin X, Lei B. The genetic spectrum and clinical features of X-linked juvenile retinoschisis in Central China. Ophthalmic Genet 2023; 44:262-270. [PMID: 36856325 DOI: 10.1080/13816810.2023.2182328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
PURPOSE X-linked juvenile retinoschisis (XLRS) is the most common congenital retinoschisis in rare vitreoretinopathy and causes visual disturbances. The study aimed to explore possible genetic mutations associated with XLRS and assess the clinical characteristics in Chinese families. METHODS Seventeen cases and thirty-four eyes of probands and thirty-nine cases and seventy-eight eyes of their guardians were recruited. Peripheral blood DNA was extracted and PCR-amplified for retinal disease second-generation panel sequencing to screen for mutated genes. Pathogenicity was referred to the guidelines of the American College of Medical Genetics and Genomics (ACMG). RESULTS A total of 17 male patients were included, with an average age of 9.73 years (range, 5 ~ 27 years). Clinical data indicate typical macular retinoschisis (97.06%), peripheral retinoschisis (46.67%), retinal holes (32.35%). Fifteen mutations (10 missense mutations, 4 shift mutations, and 3 nonsense mutations) of RS1 gene were identified, including 5 novel mutations. In novel mutations, amino acid conservation analysis shows W33, W50, E62, and G70 were highly conserved, and software predicts mutations to be pathogenic. SWISS-MODEL protein prediction software showed protein structural changes in proband 13. CONCLUSIONS We have identified and described five novel mutations in the RS1 gene and their corresponding clinical manifestations. These findings not only expand the range of known RS1 mutations and associated clinical phenotypes but also provide a basis for mechanistic studies and diagnosis of XLRS.
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Affiliation(s)
- Zhenhui Liu
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - Ju Guo
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Meng Pan
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Kunpeng Xie
- Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Liping Du
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China.,Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Xuemin Jin
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China.,Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Bo Lei
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China
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Novel Exon 7 Deletions in TSPAN12 in a Three-Generation FEVR Family: A Case Report and Literature Review. Genes (Basel) 2023; 14:genes14030587. [PMID: 36980859 PMCID: PMC10047926 DOI: 10.3390/genes14030587] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/16/2023] [Accepted: 02/23/2023] [Indexed: 03/03/2023] Open
Abstract
Familial exudative vitreoretinopathy (FEVR) is a severe clinically and genetically heterogeneous disease that is characterized by vascular disorder. FEVR exhibits strikingly variable clinical phenotypes, ranging from asymptomatic to total blindness. In this case, we present a patient who was first treated as having high myopia and retinopathy but was finally diagnosed with FEVR caused by the heterozygous deletion of exon 7 in TSPAN12 with the aid of whole genome sequencing (WGS). Typical vascular changes, including vascular leakage and an avascular zone in the peripheral retina, were observed in the proband using fundus fluorescein angiography (FFA), and the macular dragging was shown to be progressing in the follow-up visit. Furthermore, the proband showed unreported TSPAN12-related phenotypes of FEVR: ERG (full-field electroretinogram) abnormalities and retinoschisis. Only mild vascular changes were exhibited in the FFA for the other three family members who carried the same deletion of exon 7 in TSPAN12. This case expands our understanding of the phenotype resulting from TSPAN12 mutations and signifies the importance of combining both clinical and molecular analysis approaches to establish a complete diagnosis.
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Chiang TK, Yu M. Electrophysiological Evaluation of Macular Dystrophies. J Clin Med 2023; 12:jcm12041430. [PMID: 36835965 PMCID: PMC9962076 DOI: 10.3390/jcm12041430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/06/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
Macular dystrophies are a heterogeneous group of genetic disorders that often severely threatens the bilateral central vision of the affected patient. While advances in molecular genetics have been instrumental in the understanding and diagnosis of these disorders, there remains significant phenotypical variation among patients within any particular subset of macular dystrophies. Electrophysiological testing remains a vital tool not only to characterize vision loss for differential diagnosis but also to understand the pathophysiology of these disorders and to monitor the treatment effect, potentially leading to therapeutic advances. This review summarizes the application of electrophysiological testing in macular dystrophies, including Stargardt disease, bestrophinopathies, X-linked retinoschisis, Sorsby fundus dystrophy, Doyne honeycomb retina dystrophy, autosomal dominant drusen, occult macular dystrophy, North Carolina macular dystrophy, pattern dystrophy, and central areolar choroidal dystrophy.
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Wakabayashi T, Chang E, Nudleman E, El-Rayes EN, Yonekawa Y. Typical and atypical clinical presentations of X-Linked retinoschisis: A case series and literature review. Surv Ophthalmol 2023; 68:347-360. [PMID: 36724832 DOI: 10.1016/j.survophthal.2023.01.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 01/17/2023] [Accepted: 01/22/2023] [Indexed: 01/30/2023]
Abstract
X-linked retinoschisis (XLRS) is an X-linked inherited retinal dystrophy characterized by mild-to-severe visual impairment, splitting of the retinal layers, and a reduction in the dark-adapted b-wave amplitude on the electroretinogram. Typical clinical features include macular and peripheral schisis. Relatively common features reported include rhegmatogenous or tractional retinal detachment, vitreous hemorrhage, retinal pigment epithelial changes, vitreous veils, and various retinal vascular abnormalities with or without exudation. Macular hole and macular folds are atypical presentations of XLRS, along with several other rare findings. Here, we report 4 cases of XLRS with atypical clinical presentations and review the literature on XLRS, with a focus on the variable clinical features of this condition.
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Affiliation(s)
- Taku Wakabayashi
- Wills Eye Hospital, Mid Atlantic Retina, Thomas Jefferson University, Philadelphia, PA, USA
| | - Emmanuel Chang
- Retina and Vitreous of Texas, Methodist Hospital Blanton Eye Institute, Baylor College of Medicine Cullen Eye Institute, Houston, TX, USA
| | - Eric Nudleman
- Department of Ophthalmology, Shiley Eye Institute, University of California, San Diego, CA, USA
| | - Ehab N El-Rayes
- Department of Ophthalmology, Institute of Ophthalmology, Giza, Egypt; The Retina Eye Center, Cairo, Egypt
| | - Yoshihiro Yonekawa
- Wills Eye Hospital, Mid Atlantic Retina, Thomas Jefferson University, Philadelphia, PA, USA.
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A Rare Case of Juvenile X-Linked Retinoschisis. ACTA MEDICA BULGARICA 2021. [DOI: 10.2478/amb-2021-0045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Aim: To present a rare clinical case of X-linked retinoschisis, confirmed clinically, electrophysiologically and genetically.
Material and methods: A 12-year-old boy underwent detailed ophthalmic examination including fundus photography, full-field, multifocal and pattern electroretinography, visual field testing, optical coherence tomography, which established the clinical diagnosis, confirmed also genetically.
Results: The clinical findings included a slight loss of vision, central and paracentral scotomas, a characteristic spoke-wheel pattern appearance of the macula in fundoscopy and the pathognomic appearance of splitting of the retinal layers in the macula with foveal schisis with cystic spaces on OCT. Reduced cone and rod ERG responds were detected with the characteristic decreasing of b-ware near the isoelectric line. The genetic analysis found that the patient was hemizygous for the missense mutation c.598G>A (p.Arg200Cys) of RS1 gene, coming from his asymptomatic mother.
Conclusion: The comprehensive clinical, electrophysiological and genetic testing of patients with rare hereditary retinal dystrophies is essential for the correct diagnosis and the choice of therapeutic approach.
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Chen D, Zhu S. Whole-exome sequencing identifies an RS1 variant in a Chinese family with X-linked retinoschisis. Exp Ther Med 2021; 22:1406. [PMID: 34675999 PMCID: PMC8524742 DOI: 10.3892/etm.2021.10842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 07/09/2021] [Indexed: 11/05/2022] Open
Abstract
A notable behavioural feature of X-linked retinoschisis (XLRS) is extensive structural schisis (splitting) of the outer plexiform and inner nuclear layers of the neurosensory retina, which is partly combined with complications related to vitreous hemorrhage, macular holes and retinal detachment. The present study aimed to identify the pathogenic gene mutation in a three-generation Chinese family with XLRS by whole-exome sequencing (WES). The clinical information of a three-generation Chinese family with cases of XLRS was collected. WES was performed for the proband. A comparison with the human reference genome sequence (hg38) and bioinformatic analysis were performed to reveal putative variants and Sanger sequencing was applied to verify mutations in this family and healthy control participants. Intraretinal cystic spaces were detected by optical coherence tomography imaging. Structures of the wild-type and mutant retinoschisin 1 (RS1) protein were modelled by PyMol. Almost all patients had a history of vision loss and abnormal blue-purple colour vision; however, the phenotypes of the 4 patients were distinctly different. There was no linear correlation between phenotypic severity and age. A recurrent RS1 (Xp22.2) mutation (NM_000330: c.559C>T) was detected, resulting in the p.Q187X variant. According to the protein model, this variant is likely pathogenic. The present study was the first to report that RS1:c.559C>T induces XLRS in a three-generation Chinese pedigree, with the mutation leading to premature termination of translation of the RS1 protein. WES was able to diagnose XLRS, which has the characteristics of clinical and genetic heterogeneity.
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Affiliation(s)
- Doudou Chen
- Eye School of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610075, P.R. China.,Department of Ophthalmology, Ineye Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Key Laboratory of Sichuan Province Ophthalmopathy Prevention & Cure and Visual Function Protection, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China
| | - Siquan Zhu
- Eye School of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610075, P.R. China.,Department of Ophthalmology, Ineye Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Key Laboratory of Sichuan Province Ophthalmopathy Prevention & Cure and Visual Function Protection, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610032, P.R. China.,Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100006, P.R. China
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8
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HANDHELD SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY FINDINGS OF X-LINKED RETINOSCHISIS IN EARLY CHILDHOOD. Retina 2021; 40:1996-2003. [PMID: 31764609 DOI: 10.1097/iae.0000000000002688] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND/PURPOSE Using handheld spectral domain optical coherence tomography (SDOCT) imaging to investigate in vivo microanatomic retinal changes and their progression over time in young children with juvenile X-linked retinoschisis (XLRS). METHODS This retrospective analysis was of handheld SD OCT images obtained under a prospective research protocol in children who had established XLRS diagnosis based on genetic testing or clinical history. Three OCT graders performed standardized qualitative and quantitative assessment of retinal volume scans, which were divided into foveal, parafoveal, and extrafoveal regions. Visual acuity data were obtained when possible. RESULTS Spectral domain OCT images were available of both eyes in 8 pediatric patients with ages 7 months to 10 years. The schisis cavities involved inner nuclear layer in over 90% (15/16) of eyes in all 3 regions. Retinal nerve fiber and ganglion cell layer involvement was present only in the extrafoveal region in 63% (10/16) eyes and outer nuclear and plexiform layer in few others. In 7 children followed over 2 months to 15 months, the location of schisis remained consistent. Central foveal thickness decreased from the baseline to final available visit in 4/6 eyes. Ellipsoid zone disruption seemed to accompany lower visual acuity in 1/4 eyes. CONCLUSION Early in life, the SD OCT findings in XLRS demonstrate differences in schisis location in fovea-parafoveal versus extrafoveal region, possible association between poor visual acuity and degree of ellipsoid zone disruption and decrease in central foveal thickness over time in this group. Furthermore, they illustrates that the pattern of XLRS in adults is already present in very young children, and unlike in older children and adults, those presenting with earlier disease may have a more aggressive course. Further studies in this early age group may provide more insights into treatment and prevention of progressive visual impairment in children with XLRS.
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Vijaysarathy C, Babu Sardar Pasha SP, Sieving PA. Of men and mice: Human X-linked retinoschisis and fidelity in mouse modeling. Prog Retin Eye Res 2021; 87:100999. [PMID: 34390869 DOI: 10.1016/j.preteyeres.2021.100999] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/02/2021] [Accepted: 08/06/2021] [Indexed: 02/07/2023]
Abstract
X-linked Retinoschisis (XLRS) is an early-onset transretinal dystrophy, often with a prominent macular component, that affects males and generally spares heterozygous females because of X-linked recessive inheritance. It results from loss-of-function RS1 gene mutations on the X-chromosome. XLRS causes bilateral reduced acuities from young age, and on clinical exam and by ocular coherence tomography (OCT) the neurosensory retina shows foveo-macular cystic schisis cavities in the outer plexiform (OPL) and inner nuclear layers (INL). XLRS manifests between infancy and school-age with variable phenotypic presentation and without reliable genotype-phenotype correlations. INL disorganization disrupts synaptic signal transmission from photoreceptors to ON-bipolar cells, and this reduces the electroretinogram (ERG) bipolar b-wave disproportionately to photoreceptor a-wave changes. RS1 gene expression is localized mainly to photoreceptors and INL bipolar neurons, and RS1 protein is thought to play a critical cell adhesion role during normal retinal development and later for maintenance of retinal structure. Several independent XLRS mouse models with mutant RS1 were created that recapitulate features of human XLRS disease, with OPL-INL schisis cavities, early onset and variable phenotype across mutant models, and reduced ERG b-wave to a-wave amplitude ratio. The faithful phenotype of the XLRS mouse has assisted in delineating the disease pathophysiology. Delivery to XLRS mouse retina of an AAV8-RS1 construct under control of the RS1 promoter restores the retinal structure and synaptic function (with increase of b-wave amplitude). It also ameliorates the schisis-induced inflammatory microglia phenotype toward a state of immune quiescence. The results imply that XLRS gene therapy could yield therapeutic benefit to preserve morphological and functional retina particularly when intervention is conducted at earlier ages before retinal degeneration becomes irreversible. A phase I/IIa single-center, open-label, three-dose-escalation clinical trial reported a suitable safety and tolerability profile of intravitreally administered AAV8-RS1 gene replacement therapy for XLRS participants. Dose-related ocular inflammation occurred after dosing, but this resolved with topical and oral corticosteroids. Systemic antibodies against AAV8 increased in dose-dependent fashion, but no antibodies were observed against the RS1 protein. Retinal cavities closed transiently in one participant. Technological innovations in methods of gene delivery and strategies to further reduce immune responses are expected to enhance the therapeutic efficacy of the vector and ultimate success of a gene therapy approach.
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Affiliation(s)
| | | | - Paul A Sieving
- National Eye Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA; Department of Ophthalmology, University of California Davis, 95817, USA.
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10
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Gao F, Dong J, Wang D, Chen F, Hu F, Chang Q, Xu P, Liu W, Li J, Huang Y, Wu J, Xu G. Comprehensive analysis of genetic and clinical characteristics of 30 patients with X-linked juvenile retinoschisis in China. Acta Ophthalmol 2021; 99:e470-e479. [PMID: 33124204 PMCID: PMC8359357 DOI: 10.1111/aos.14642] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 09/05/2020] [Accepted: 09/06/2020] [Indexed: 12/13/2022]
Abstract
Purpose To provides the clinical and genetic characteristics of a series of Chinese patients with X‐linked juvenile retinoschisis (XLRS) through multimodal imaging and next‐generation sequencing. Methods Thirty patients (60 eyes) from 29 unrelated families of Chinese origin with XLRS were screened using multigene panel testing, and underwent a complete clinical evaluation. All variants identified in this study and reported in the Human Gene Mutation Database were analysed. Results Twenty‐five distinct variants in the retinoschisin gene were identified, of which eight were novel, and one was de novo. Missense mutations were the most prevalent type, and mutation hot spot was localized in the discoidin domain. The mean Snellen best‐corrected visual acuity was 0.28 ± 0.17. Of all eyes presenting with schisis, 92.86% had lamellar schisis and 62.5% had peripheral schisis. Schisis changes mostly involved inner and outer nuclear layers. X‐linked juvenile retinoschisis (XLRS) patients had a high incidence of complications, and peripheral schisis was a risk factor for it. No obvious genotype–phenotype association was observed. Conclusion This study provides comprehensive analyses of the genetic and clinical characteristics of XLRS in a cohort of Chinese patients. The fourth de novo mutation in RS1 was identified. And we show that XLRS has a wide spectrum of clinical characteristics; hence, molecular diagnosis is crucial for its diagnosis, differential diagnosis and genetic counselling. Peripheral schisis is a risk factor for the high incidence of complications, and no clear genotype–phenotype correlations were found.
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Affiliation(s)
- Feng‐Juan Gao
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Jian‐Hong Dong
- Department of Ophthalmology Central Hospital of Xuhui District Shanghai China
| | - Dan‐Dan Wang
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Fang Chen
- BGI‐Shenzhen Shenzhen China
- Laboratory of Genomics and Molecular Biomedicine Department of Biology University of Copenhagen Copenhagen Denmark
- Shenzhen Engineering Laboratory for Birth Defects Screening BGI‐Shenzhen Shenzhen China
| | - Fang‐Yuan Hu
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Qing Chang
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Ping Xu
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Wei Liu
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Jian‐Kang Li
- BGI‐Shenzhen Shenzhen China
- Department of Computer Science City University of Hong Kong Kowloon Hong Kong SAR China
| | - Ying Huang
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
| | - Ji‐Hong Wu
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
| | - Ge‐Zhi Xu
- Eye Institute Eye and ENT Hospital College of Medicine Fudan University Shanghai China
- Shanghai Key Laboratory of Visual Impairment and Restoration Science and Technology Commission of Shanghai Municipality Shanghai China
- Key Laboratory of Myopia (Fudan University) Chinese Academy of Medical Sciences National Health Commission Shanghai China
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Zhang N, Peng Y, Zhou N, Qi Y. A novel mutation in the RS1 gene in a Chinese family with X-linked congenital retinoschisis. Exp Ther Med 2020; 21:124. [PMID: 33335587 PMCID: PMC7739845 DOI: 10.3892/etm.2020.9556] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 10/30/2020] [Indexed: 11/20/2022] Open
Abstract
The purpose of the present study was to assess the clinical characteristics of X-linked retinoschisis (XLRS) in a Chinese family over a 7-year period with the aim of identifying possible genetic mutations associated with this disease. A total of 2 male siblings from a family with XLRS were followed up for 7 years and the best-corrected visual acuity and data obtained using slit-lamp microscopy, indirect ophthalmoscopy, fundus photography, spectral domain-optical coherence tomography (OCT), fundus autofluorescence and fundus fluorescence (FFA) and multifocal electroretinograms (ERG) were examined. The coding regions of the retinoschisin 1 (RS1) gene were amplified by PCR and sequenced directly. The proband exhibited blurred vision at 12 years old and was indicated to exhibit a typical phenotype of XLRS at 30 years old. The elder brother exhibited blurred vision at 11 years old and was diagnosed with XLRS at 33 years old. There was no change in the best-corrected visual acuities in the two patients over the 7 years. The OCT results suggested that there were intraretinal cysts and macular atrophy in the eyes of the older sibling, whilst a ‘spoke-wheel’ pattern was present in the macula of the younger sibling. In addition, OCT examination revealed foveal schisis. FFA analysis indicated a hyperfluorescent signal in the central macula. Multifocal ERG recordings indicated that responses were markedly reduced in the central and outer rings bilaterally. The central retinal thickness of the younger sibling increased but the central retinal thickness of the older sibling was not changed during the 7 years. Sequencing analysis revealed that the mutation was c.366G>A (p.Trp122*) in exon 5 of Xp22.1. Gene mutation analysis indicated that the affected male siblings harbored a Trp122* (c.366G>A) mutation, while the patients' mother was demonstrated to be a heterozygous carrier of the pathogenic mutation. To conclude, the present study discovered a novel XLRS mutation in a Chinese family, where the Trp122* mutation caused a significant change in the function of the RS1 protein. Over the 7 years of observation, although the vision was not significantly impaired in the two patients examined, the central retinal thickness of the younger sibling increased but the central retinal thickness of the older sibling was not altered.
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Affiliation(s)
- Na Zhang
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Yao Peng
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Nan Zhou
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Yanhua Qi
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
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C Parameswarappa D, Belenje A, Rani PK. Multimodal imaging of bilateral macular hole in X-linked retinoschisis. BMJ Case Rep 2020; 13:13/9/e238354. [DOI: 10.1136/bcr-2020-238354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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13
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Pennesi ME, Birch DG, Jayasundera KT, Parker M, Tan O, Gurses-Ozden R, Reichley C, Beasley KN, Yang P, Weleber RG, Bennett LD, Heckenlively JR, Kothapalli K, Chulay JD, For The Xlrs-Study Group. Prospective Evaluation of Patients With X-Linked Retinoschisis During 18 Months. Invest Ophthalmol Vis Sci 2019; 59:5941-5956. [PMID: 30551202 PMCID: PMC6295939 DOI: 10.1167/iovs.18-24565] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Prospective evaluation of patients with X-linked retinoschisis (XLRS). Methods Fifty-six males XLRS patients, age ≥7 years, had retinal structure and function tests performed every 6 months during an 18-month period. Results Best corrected visual acuity (BCVA) was abnormal (mean ± SD logMAR 0.57 ± 0.32 OD and 0.50 ± 0.27 OS), with weak correlation between visual acuity and age (R = -0.24, P = 0.0095). Mean cyst cavity volume (CCV) determined on optical coherence tomography showed weak correlation with age (R = -0.33, P = 0.0009) and no correlation with visual acuity. Subjects had modest reduction in mean kinetic and static perimetry results, reduced b-wave amplitude on electroretinography, abnormal reading speed results, and decreased visual function quality of life scores. Contrast sensitivity results were normal in 85 of 99 eyes tested. Most subjects had no meaningful change in BCVA during follow-up. Subjects who started carbonic anhydrase inhibitor (CAI) treatment at enrollment had improved BCVA (mean ± SD change 3.15 ± 7.8 ETDRS letters, with increase of ≥15 ETDRS letters at 8 of 110 visits [in 3 subjects]). There were no significant changes in other parameters tested. Conclusions Structural and functional results were stable during the 18-month follow-up period. Some patients starting CAI treatment at the baseline visit showed improvement in BCVA that was not correlated with changes in CCV. Natural history data such as these will be important for comparisons to the changes in measures of retinal structure and function following gene replacement therapy in patients with XLRS.
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Affiliation(s)
- Mark E Pennesi
- Casey Eye Institute, Oregon Health & Sciences University, Portland, Oregon, United States
| | - David G Birch
- Retina Foundation of the Southwest, Dallas, Texas, United States
| | | | - Maria Parker
- Casey Eye Institute, Oregon Health & Sciences University, Portland, Oregon, United States
| | - Ou Tan
- Casey Eye Institute, Oregon Health & Sciences University, Portland, Oregon, United States
| | - Rabia Gurses-Ozden
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
| | - Carrie Reichley
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
| | - Kathleen N Beasley
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
| | - Paul Yang
- Casey Eye Institute, Oregon Health & Sciences University, Portland, Oregon, United States
| | - Richard G Weleber
- Casey Eye Institute, Oregon Health & Sciences University, Portland, Oregon, United States
| | - Lea D Bennett
- Retina Foundation of the Southwest, Dallas, Texas, United States
| | - John R Heckenlively
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, United States
| | | | - Jeffrey D Chulay
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
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14
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A case of X-linked retinoschisis with atypical fundus appearance. Doc Ophthalmol 2019; 139:75-81. [PMID: 31006083 DOI: 10.1007/s10633-019-09698-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/10/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE Mutations in the RS1 gene are known to cause retinoschisis, an X-linked hereditary retinal degeneration. Here, we present a case of atypical retinoschisis with clinical findings of retinoschisis and retinitis pigmentosa. METHODS This report is an observational case report. The detailed ophthalmological examinations included visual field determination, multimodal imaging and electrophysiological recordings. Targeted next-generation sequencing of a retinal disease gene panel was performed. RESULTS The 55-year-old male, highly hyperopic patient, presented with a best-corrected Snellen visual acuity of 20/100 in the right eye and 20/400 in the left eye. In the kinetic visual field, there was a superior scotoma, as well as a ring scotoma in the inferior hemisphere in the right eye and a concentric visual field constriction to 10° in the left eye. Funduscopy revealed marked pigmentary changes (i.e. bone spicules) in the mid-periphery bilaterally and symmetrically, as well as two small intra-retinal haemorrhages in the left eye. Full-field electroretinography recordings showed extinguished rod and cone responses. Diagnostic-genetic testing revealed a hemizygous missense mutation in the RS1 gene (c.305G > A; p.Arg102Gln) was identified. CONCLUSION We present a case of atypical retinoschisis with clinical findings of retinitis pigmentosa.
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15
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Kondo H, Oku K, Katagiri S, Hayashi T, Nakano T, Iwata A, Kuniyoshi K, Kusaka S, Hiyoshi A, Uchio E, Kondo M, Oishi N, Kameya S, Mizota A, Naoi N, Ueno S, Terasaki H, Morimoto T, Iwaki M, Yoshitake K, Iejima D, Fujinami K, Tsunoda K, Shinoda K, Iwata T. Novel mutations in the RS1 gene in Japanese patients with X-linked congenital retinoschisis. Hum Genome Var 2019; 6:3. [PMID: 30652005 PMCID: PMC6325138 DOI: 10.1038/s41439-018-0034-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 11/12/2018] [Accepted: 12/09/2018] [Indexed: 12/04/2022] Open
Abstract
X-linked congenital retinoschisis (XLRS) is an inherited retinal disorder characterized by reduced central vision and schisis of the macula and peripheral retina. XLRS is caused by mutations in the RS1 gene. We have identified 37 different mutations in the RS1 gene, including 12 novel mutations, in 67 Japanese patients from 56 XLRS families. We present clinical features of these patients in relation to the associated mutations.
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Affiliation(s)
- Hiroyuki Kondo
- 1Department of Ophthalmology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kazuma Oku
- 1Department of Ophthalmology, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Satoshi Katagiri
- 2Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Takaaki Hayashi
- 2Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Tadashi Nakano
- 2Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Akiko Iwata
- 3Department of Ophthalmology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Kazuki Kuniyoshi
- 3Department of Ophthalmology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Shunji Kusaka
- 3Department of Ophthalmology, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Atsushi Hiyoshi
- 4Department of Ophthalmology, Fukuoka University, Fukuoka, Japan
| | - Eiichi Uchio
- 4Department of Ophthalmology, Fukuoka University, Fukuoka, Japan
| | - Mineo Kondo
- 5Department of Ophthalmology, Mie University Graduate School of Medicine, Tsu, Japan
| | - Noriko Oishi
- 6Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan
| | - Shuhei Kameya
- 6Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Chiba, Japan
| | - Atsushi Mizota
- 7Department of Ophthalmology, Teikyo University, Tokyo, Japan
| | - Nobuhisa Naoi
- 8Department of Ophthalmology, Miyazaki University, Miyazaki, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nogoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nogoya University Graduate School of Medicine, Nagoya, Japan
| | - Takeshi Morimoto
- 10Department of Applied Visual Science, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Masayoshi Iwaki
- 11Department of Ophthalmology, Aichi Medical University, Nagakute, Japan
| | - Kazutoshi Yoshitake
- 12Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Daisuke Iejima
- 12Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Kaoru Fujinami
- 13Division of Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Kazushige Tsunoda
- 13Division of Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Kei Shinoda
- 14Department of Ophthalmology, Saitama Medical University, Moroyama, Japan
| | - Takeshi Iwata
- 12Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
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16
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Orès R, Mohand-Said S, Dhaenens CM, Antonio A, Zeitz C, Augstburger E, Andrieu C, Sahel JA, Audo I. Phenotypic Characteristics of a French Cohort of Patients with X-Linked Retinoschisis. Ophthalmology 2018; 125:1587-1596. [PMID: 29739629 DOI: 10.1016/j.ophtha.2018.03.057] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 03/25/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022] Open
Abstract
PURPOSE To analyze the retinal structure in patients with X-linked retinoschisis (XLRS) using spectral-domain OCT and to correlate the morphologic findings with visual acuity, electroretinographic results, and patient age. DESIGN Retrospective, observational study. PARTICIPANTS Data from 52 consecutive male patients with molecularly confirmed XLRS were collected retrospectively. METHODS Complete clinical evaluation included best-corrected visual acuity, full-field electroretinography, fundus photography, spectral-domain OCT, and fundus autofluorescence. Spectral-domain OCT images were analyzed to determine full thickness of the retina and tomographic structural changes. MAIN OUTCOME MEASURES Relationships between age, OCT, and visual acuity were assessed. RESULTS One hundred four eyes of 52 patients were included. The mean age at inclusion was 24±15 years (range, 3-57 years). The best-corrected visual acuity ranged from no light perception to 0.1 logarithm of the minimum angle of resolution (mean, 0.6±0.38 logarithm of the minimum angle of resolution). Macular schisis was found in 88% of eyes and macular atrophy was found in 11% of eyes, whereas peripheral schisis was present in 30% of eyes. A spoke-wheel pattern of high and low intensity was the most frequently observed fundus autofluorescence abnormality (51/94 eyes [54%]). The b-to-a amplitude ratio on bright-flash dark-adapted electroretinography was reduced significantly in 45 of 64 eyes (70%). Spectral-domain OCT was available for 97 eyes and showed foveoschisis in 76 of 97 eyes (78%), parafoveal schisis in 10 of 97 eyes (10%), and foveal atrophy in 11 of 97 eyes (11%). Mean central macular thickness (CMT) was of 373.6±140 μm. Cystoid changes were localized mainly in the inner nuclear layer (85/97 eyes [88%]). Qualitative defects in photoreceptor structures were found in most eyes (79/97 eyes [81%]), and the most frequent abnormality was an interruption of the photoreceptor cell outer segment tips (79/79 eyes [100%]). Older age correlated well with lower CMT (correlation coefficient [CC], -0.44; P < 0.001) and with lower photoreceptor outer segment (PROS) length (CC, -0.42; P < 0.001). Lower visual acuity correlated strongly with lower PROS length (CC, -0.53; P < 0.001). CONCLUSIONS This study underlined the wide variety of clinical features of XLRS. It highlighted the correlation between visual acuity, patient age, and OCT features, emphasizing the relevance of the latter as potential outcome measure in clinical trials.
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Affiliation(s)
- Raphaëlle Orès
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France
| | - Saddek Mohand-Said
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; INSERM, CNRS, Institut de la Vision, Sorbonne Université, Paris, France
| | - Claire-Marie Dhaenens
- Department of Biochemistry and Molecular Biology-UF Génopathies, Université Lille, Inserm UMR-S 1172, CHU Lille, Lille, France
| | - Aline Antonio
- INSERM, CNRS, Institut de la Vision, Sorbonne Université, Paris, France
| | - Christina Zeitz
- INSERM, CNRS, Institut de la Vision, Sorbonne Université, Paris, France
| | - Edouard Augstburger
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France
| | - Camille Andrieu
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France
| | - José-Alain Sahel
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; INSERM, CNRS, Institut de la Vision, Sorbonne Université, Paris, France; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Isabelle Audo
- Centre de Maladies Rares "Dystrophies Rétiniennes d'Origine Génétique," DHU Sight Restore INSERM-DHOS CIC 1423, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; INSERM, CNRS, Institut de la Vision, Sorbonne Université, Paris, France.
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Schaefer EAF, Whiting REH, Pearce JW, Grahn BH, Hamm CW, Moore CP, Narfström KL. Bilateral retinoschisis in a dog: A veterinary clinical application for optical coherence tomography. Vet Ophthalmol 2018. [DOI: 10.1111/vop.12557] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elizabeth A. F. Schaefer
- Department of Veterinary Medicine and Surgery; University of Missouri College of Veterinary Medicine; Columbia MO USA
| | | | - Jacqueline W. Pearce
- Department of Veterinary Medicine and Surgery; University of Missouri College of Veterinary Medicine; Columbia MO USA
| | - Bruce H. Grahn
- Department of Small Animal Clinical Sciences; University of Saskatchewan; Saskatoon SK Canada
| | - Charles W. Hamm
- Department of Ophthalmology; School of Medicine; Columbia MO USA
| | - Cecil P. Moore
- Department of Veterinary Medicine and Surgery; University of Missouri College of Veterinary Medicine; Columbia MO USA
| | - Kristina L. Narfström
- Department of Veterinary Medicine and Surgery; University of Missouri College of Veterinary Medicine; Columbia MO USA
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Neriyanuri S, Dhandayuthapani S, Arunachalam JP, Raman R. Phenotypic characterization of X-linked retinoschisis: Clinical, electroretinography, and optical coherence tomography variables. Indian J Ophthalmol 2017; 64:513-7. [PMID: 27609164 PMCID: PMC5026077 DOI: 10.4103/0301-4738.190140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aims: To study the phenotypic characteristics of X-linked retinoschisis (XLRS) and report the clinical, electroretinogram (ERG), and optical coherence tomography (OCT) variables in Indian eyes. Design: A retrospective study. Materials and Methods: Medical records of 21 patients with retinoschisis who were genetically confirmed to have RS1 mutation were reviewed. The phenotype characterization included the age of onset, best-corrected visual acuity, refractive error, fundus findings, OCT, and ERG. Statistical Analysis Used: Data from both the eyes were used for analysis. A P < 0.05 was set as statistical significance. Data were not normally distributed (P < 0.05, Shapiro wilk); hence, nonparametric tests were used for statistical analysis. Results: All were males whose mean age of presentation was 9 years. Visual acuity was moderately impaired (median 0.6 logMAR, interquartile range: 0.47, 1) in these eyes with a hyperopic refractive error of median +1.75 Ds (interquartile range: +0.50 Ds, +4.25 Ds). About 54.7% of the eyes had both foveal and peripheral schisis, isolated foveal schisis was seen in 28.5% of the eyes, and schisis with retinal detachment was seen in 16.6% of the eyes. The inner nuclear layer was found to be commonly involved in the schisis, followed by outer nuclear and plexiform layers as evident on OCT. On ERG, a- and b-wave amplitudes were significantly reduced in eyes with foveal and peripheral schisis when compared to the eyes with only foveal schisis (P < 0.05). Conclusions: XLRS has phenotypic heterogeneity as evident on OCT, ERG, and clinical findings.
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Affiliation(s)
- Srividya Neriyanuri
- Department of Optometry, Elite School of Optometry, Chennai and Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Sudha Dhandayuthapani
- Department of Genetics and Molecular Biology, Vision Research Foundation, Sankara Nethralaya, Chennai, Tamil Nadu, India
| | - Jayamuruga Pandian Arunachalam
- Department of Genetics and Molecular Biology, Vision Research Foundation, Sankara Nethralaya, Chennai, Tamil Nadu, India
| | - Rajiv Raman
- Department of Vitreo-retina, Shri Bhagwan Mahaveer Vitreoretinal Services, Sankara Nethralaya, Chennai, Tamil Nadu, India
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Piermarocchi S, Miotto S, Colavito D, Del Giudice E, Leon A, Maritan V, Piermarocchi R, Tormene AP. Long-term rearrangement of retinal structures in a novel mutation of X-linked retinoschisis. Biomed Rep 2017; 7:241-246. [PMID: 28811895 DOI: 10.3892/br.2017.954] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 06/06/2017] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to report a novel mutation in the retinoschisin 1 (RS1) gene in a Caucasian family affected by X-linked juvenile retinoschisis (XLRS) and to describe the long-term modification of retinal structure. Two brothers with an early onset maculopathy were diagnosed with XLRS. Fundus photography, fluorescein angiography, spectral domain optical coherence tomography and electroretinogram analyses were performed. Their sister was also examined. All subjects were screened for mutations in the RS1 gene. XLRS patients demonstrated a marked reduction of best-corrected visual acuity. SD-OCT scans reported a cystic degeneration primarily involving the inner nuclear layer, though some cysts were detected in the outer plexiform layer and in the ganglion cell layer. During the ten-year follow-up, a progressive retinal thickening and coalescence of the cysts was observed. Genetic testing revealed a novel mutation (p.Ile212Asn) in the RS1 gene in both XLRS patients, whereas their sister was not a genetic carrier. Several mutations of the RS1 gene were recognized to be responsible for XLRS. Although the correspondence between genotype and phenotype is still under debate, is reasonable that siblings affected by XLRS could share other genetic and/or epigenetic factors capable to influence clinical course of the disease.
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Affiliation(s)
| | - Stefania Miotto
- Ophthalmic Department, Unità Locale Socio-Sanitaria 6 Euganea, Camposampiero, I-35012 Padua, Italy
| | - Davide Colavito
- Research and Innovation (R&I Genetics) Srl, I-35127 Padua, Italy
| | - Elda Del Giudice
- Research and Innovation (R&I Genetics) Srl, I-35127 Padua, Italy
| | - Alberta Leon
- Research and Innovation (R&I Genetics) Srl, I-35127 Padua, Italy
| | - Veronica Maritan
- Ophthalmic Department, ULSS 6 Euganea, Monselice, I-35043 Padua, Italy
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Coussa RG, Kapusta MA. Treatment of cystic cavities in X-linked juvenile retinoschisis: The first sequential cross-over treatment regimen with dorzolamide. Am J Ophthalmol Case Rep 2017; 8:1-3. [PMID: 29260104 PMCID: PMC5731553 DOI: 10.1016/j.ajoc.2017.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 07/03/2017] [Accepted: 07/19/2017] [Indexed: 11/30/2022] Open
Abstract
Purpose To report the first sequential cross-over treatment with the longest ophthalmic follow-up in a case of X-linked juvenile retinoschisis (XLRS) successfully treated with topical dorzolamide. Observations A healthy 34 year-old man presented with one month history of decreased visual acuity in his left eye. Funduscopy was significant for a blunted and cystoid-like foveal reflex in both eyes. The macular OCT showed cystic foveal changes OU. The patient was diagnosed with XLRS and was observed. On two subsequent follow-ups, a significant decrease in the patient's visual acuity warranted the use of topical dorzolamide for treating the cystic foveal changes, which completely resolved two months post-treatment initiation. Conclusion and importance Previous reports showed the benefit of dorzolamide in treating foveal cystic cavities in XLRS. To our knowledge, this is the first case of XLRS demonstrating the benefits of topical dorzolamide based on a sequential cross-over treatment regimen. It may also represent a case with the longest ophthalmic follow-up providing, in consequence, long-term understanding of the natural history and complications of this rare disease After ruling out major causes of cystoid macular edema, XLRS patients presenting with worsening of their visual acuities due to larger cystic macular changes may benefit from an alternating ON/OFF regimen of topical dorzolamide, which offers a significant treatment advantage outweighing its well-known side effects. Our study consolidates the importance of “medication vacation” by showing its efficacy in providing anatomical and visual functional improvements in patients with chronic cystic macular changes.
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Affiliation(s)
- Razek Georges Coussa
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, 3755 Côte-Ste-Catherine Road, E-030, Montreal, Quebec, H3T 1E2, Canada
| | - Michael Alton Kapusta
- Department of Ophthalmology, Jewish General Hospital, McGill University Health Center, 3755 Côte-Ste-Catherine Road, E-030, Montreal, Quebec, H3T 1E2, Canada
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Murro V, Caputo R, Bacci GM, Sodi A, Mucciolo DP, Bargiacchi S, Giglio SR, Virgili G, Rizzo S. Case report of an atypical early onset X-linked retinoschisis in monozygotic twins. BMC Ophthalmol 2017; 17:19. [PMID: 28235399 PMCID: PMC5324242 DOI: 10.1186/s12886-017-0406-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 01/25/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND X-linked Retinoschisis (XLRS) is one of the most common macular degenerations in young males, with a worldwide prevalence ranging from 1:5000 to 1:20000. Clinical diagnosis of XLRS can be challenging due to the highly variable phenotypic presentation and limited correlation has been identified between mutation type and disease severity or progression. CASE PRESENTATION We report the atypical early onset of XLRS in 3-month-old monozygotic twins. Fundus examination was characterized by severe bullous retinal schisis with pre-retinal and intraretinal haemorrhages. Molecular genetic analysis of the RS1 was performed and the c.288G > A (p. Trp96Ter) mutation was detected in both patients. CONCLUSIONS Early onset XLRS is associated with a more progressive form of the disease, characterized by large bullous peripheral schisis involving the posterior pole, vascular abnormalities and haemorrhages. The availability of specific technology permitted detailed imaging of the clinical picture of unusual cases of XLRS. The possible relevance of modifying genes should be taken into consideration for the future development of XLRS gene therapy.
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Affiliation(s)
- Vittoria Murro
- Department of Translational Surgery and Medicine, Eye Clinic, University of Florence, Largo Brambilla, Florence, 3-50134, Italy
| | - Roberto Caputo
- Ophthalmology Unit, Department of Pediatrics, Anna Meyer Children's University Hospital, Florence, Italy
| | - Giacomo Maria Bacci
- Ophthalmology Unit, Department of Pediatrics, Anna Meyer Children's University Hospital, Florence, Italy
| | - Andrea Sodi
- Department of Translational Surgery and Medicine, Eye Clinic, University of Florence, Largo Brambilla, Florence, 3-50134, Italy
| | - Dario Pasquale Mucciolo
- Department of Translational Surgery and Medicine, Eye Clinic, University of Florence, Largo Brambilla, Florence, 3-50134, Italy.
| | - Sara Bargiacchi
- Genetics and Molecular Medicine Unit, Department of Pediatrics, Anna Meyer Children's University Hospital, Florence, Italy
| | - Sabrina Rita Giglio
- Genetics and Molecular Medicine Unit, Department of Pediatrics, Anna Meyer Children's University Hospital, Florence, Italy
| | - Gianni Virgili
- Department of Translational Surgery and Medicine, Eye Clinic, University of Florence, Largo Brambilla, Florence, 3-50134, Italy
| | - Stanislao Rizzo
- Department of Translational Surgery and Medicine, Eye Clinic, University of Florence, Largo Brambilla, Florence, 3-50134, Italy
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22
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Plössl K, Weber BHF, Friedrich U. The X-linked juvenile retinoschisis protein retinoschisin is a novel regulator of mitogen-activated protein kinase signalling and apoptosis in the retina. J Cell Mol Med 2016; 21:768-780. [PMID: 27995734 PMCID: PMC5345684 DOI: 10.1111/jcmm.13019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 09/26/2016] [Indexed: 02/01/2023] Open
Abstract
X-linked juvenile retinoschisis (XLRS) is a hereditary retinal dystrophy in young males, caused by mutations in the RS1 gene. The function of the encoded protein, termed retinoschisin, and the molecular mechanisms underlying XLRS pathogenesis are still unresolved, although a direct interaction partner of the secreted retinoschisin, the retinal Na/K-ATPase, was recently identified. Earlier gene expression studies in retinoschisin-deficient (Rs1h-/Y ) mice provided a first indication of pathological up-regulation of mitogen-activated protein (MAP) kinase signalling in disease pathogenesis. To further investigate the role for retinoschisin in MAP kinase regulation, we exposed Y-79 cells and murine Rs1h-/Y retinae to recombinant retinoschisin and the XLRS-associated mutant RS1-C59S. Although normal retinoschisin stably bound to retinal cells, RS1-C59S exhibited a strongly reduced binding affinity. Simultaneously, exposure to normal retinoschisin significantly reduced phosphorylation of C-RAF and MAP kinases ERK1/2 in Y-79 cells and murine Rs1h-/Y retinae. Expression of MAP kinase target genes C-FOS and EGR1 was also down-regulated in both model systems. Finally, retinoschisin treatment decreased pro-apoptotic BAX-2 transcript levels in Y-79 cells and Rs1h-/Y retinae. Upon retinoschisin treatment, these cells showed increased resistance against apoptosis, reflected by decreased caspase-3 activity (in Y-79 cells) and increased photoreceptor survival (in Rs1h-/Y retinal explants). RS1-C59S did not influence C-RAF or ERK1/2 activation, C-FOS or EGR1 expression, or apoptosis. Our data imply that retinoschisin is a novel regulator of MAP kinase signalling and exerts an anti-apoptotic effect on retinal cells. We therefore discuss that disturbances of MAP kinase signalling by retinoschisin deficiency could be an initial step in XLRS pathogenesis.
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Affiliation(s)
- Karolina Plössl
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany
| | - Bernhard H F Weber
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany
| | - Ulrike Friedrich
- Institute of Human Genetics, University of Regensburg, Regensburg, Germany
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Katagiri S, Tanaka S, Yokoi T, Hayashi T, Matsuzaka E, Ueda K, Yoshida-Uemura T, Arakawa A, Nishina S, Kadonosono K, Azuma N. Clinical features of a toddler with bilateral bullous retinoschisis with a novel RS1 mutation. Am J Ophthalmol Case Rep 2016; 5:76-80. [PMID: 29503952 PMCID: PMC5758021 DOI: 10.1016/j.ajoc.2016.12.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/30/2016] [Accepted: 12/08/2016] [Indexed: 11/03/2022] Open
Abstract
Purpose To report the clinical and genetic findings of a male toddler who presented bilateral bullous retinoschisis with a novel RS1 mutation. Observations This is an observational case report of a patient referred to our hospital with esotropia. A comprehensive ophthalmic examination was performed with the boy (age, 1 year 4 months) under general anesthesia that included fundus examinations, fluorescein angiography (FA), swept-source optical coherence tomography (SS-OCT), and full-field electroretinography (FF-ERG). Genetic analysis of the coding region in the RS1 gene was performed by Sanger sequencing for the patient and mother. There was a family history of X-linked retinoschisis (XLRS). Fundus examinations and FA showed bullous retinoschisis bilaterally in the inferior retina. The SS-OCT images showed two kinds of schisis in the inner nuclear layer (INL) and more proximally. In general, the inner plexiform layer, ganglion cell layer, and retinal nerve fiber layer are in the proximal INL; however, in this case there was hyperreflective tissue with a rough surface instead of normal retinal layers. In addition, in the schisis cavity between the hyperreflective tissue and separated retina, a number of hyperreflective fiber-like strands arose from the hyperreflective tissue and extended to the schisis cavity. During the follow-up period, the bullous retinoschisis collapsed spontaneously in the right eye. FF-ERG showed a reduced b-wave and relatively preserved a-wave in all components. Genetic analysis showed a novel RS1 mutation (c.185_186insT, p.E62DfsX24 in exon 4) in the patient and mother. Conclusions and importance We report the detailed retinal structure in a genetically identified case of bullous retinoschisis. The notable finding was that the cavity of bullous retinoschisis contained a number of fiber-like strands as observed in the cavity of typical retinoschisis.
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Affiliation(s)
- Satoshi Katagiri
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan.,Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Shin Tanaka
- Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Tadashi Yokoi
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Emiko Matsuzaka
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan
| | - Kazuko Ueda
- Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Tomoyo Yoshida-Uemura
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan
| | - Akira Arakawa
- Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Sachiko Nishina
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan
| | - Kazuaki Kadonosono
- Department of Ophthalmology, Yokohama City University Medical Center, Yokohama, Japan
| | - Noriyuki Azuma
- Department of Ophthalmology and Laboratory for Visual Science, National Center for Child Health and Development, Tokyo, Japan
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Xiao Y, Liu X, Tang L, Wang X, Coursey TG, Coursy T, Guo X, Li Z. X-Linked Retinoschisis: Phenotypic Variability in a Chinese Family. Sci Rep 2016; 6:20118. [PMID: 26823236 PMCID: PMC4731765 DOI: 10.1038/srep20118] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 12/29/2015] [Indexed: 11/09/2022] Open
Abstract
X-linked juvenile retinoschisis (XLRS), a leading cause of juvenile macular degeneration, is characterized by a spoke-wheel pattern in the macular region of the retina and splitting of the neurosensory retina. Our study is to describe the clinical characteristics of a four generations of this family (a total of 18 members)with X-linked retinoschisis (XLRS) and detected a novel mutations of c.3G > A (p.M1?) in the initiation codon of the RS1 gene. by direct sequencing.Identification of this mutation in this family provides evidence about potential genetic or environmental factors on its phenotypic variance, as patients presented with different phenotypes regardless of having the same mutation. Importantly, OCT has proven vital for XLRS diagnosis in children.
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Affiliation(s)
- Yangyan Xiao
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xiao Liu
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Luosheng Tang
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xia Wang
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | | | - Terry Coursy
- Cullen eye institute, Baylor College of Medicine, Houston, Texas, USA
| | - Xiaojian Guo
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhuo Li
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan, China
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Jeffrey BG, Cukras CA, Vitale S, Turriff A, Bowles K, Sieving PA. Test-Retest Intervisit Variability of Functional and Structural Parameters in X-Linked Retinoschisis. Transl Vis Sci Technol 2014; 3:5. [PMID: 25346871 DOI: 10.1167/tvst.3.5.5] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 06/30/2014] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To examine the variability of four outcome measures that could be used to address safety and efficacy in therapeutic trials with X-linked juvenile retinoschisis. METHODS Seven men with confirmed mutations in the RS1 gene were evaluated over four visits spanning 6 months. Assessments included visual acuity, full-field electroretinograms (ERG), microperimetric macular sensitivity, and retinal thickness measured by optical coherence tomography (OCT). Eyes were separated into Better or Worse Eye groups based on acuity at baseline. Repeatability coefficients were calculated for each parameter and jackknife resampling used to derive 95% confidence intervals (CIs). RESULTS The threshold for statistically significant change in visual acuity ranged from three to eight letters. For ERG a-wave, an amplitude reduction greater than 56% would be considered significant. For other parameters, variabilities were lower in the Worse Eye group, likely a result of floor effects due to collapse of the schisis pockets and/or retinal atrophy. The criteria for significant change (Better/Worse Eye) for three important parameters were: ERG b/a-wave ratio (0.44/0.23), point wise sensitivity (10.4/7.0 dB), and central retinal thickness (31%/18%). CONCLUSIONS The 95% CI range for visual acuity, ERG, retinal sensitivity, and central retinal thickness relative to baseline are described for this cohort of participants with X-linked juvenile retinoschisis (XLRS). TRANSLATIONAL RELEVANCE A quantitative understanding of the variability of outcome measures is vital to establishing the safety and efficacy limits for therapeutic trials of XLRS patients.
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Affiliation(s)
- Brett G Jeffrey
- National Eye Institute, National Institutes of Health, Bethesda, MD
| | | | - Susan Vitale
- National Eye Institute, National Institutes of Health, Bethesda, MD
| | - Amy Turriff
- National Eye Institute, National Institutes of Health, Bethesda, MD
| | - Kristin Bowles
- Current address: College of Optometry, University of Houston, TX ; National Eye Institute, National Institutes of Health, Bethesda, MD
| | - Paul A Sieving
- National Eye Institute, National Institutes of Health, Bethesda, MD
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Abstract
X-linked juvenile retinoschisis (XLRS) is one of the most common genetic causes of juvenile progressive retinal-vitreal degeneration in males. To date, more than 196 different mutations of the RS1 gene have been associated with XLRS. The mutation spectrum is large and the phenotype variable. This review will focus on the clinical features of XLRS and examine the relationship between phenotype and genotype.
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Affiliation(s)
- David Y Kim
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston , Massachusetts , USA
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Vincent A, Robson AG, Neveu MM, Wright GA, Moore AT, Webster AR, Holder GE. A phenotype-genotype correlation study of X-linked retinoschisis. Ophthalmology 2013; 120:1454-64. [PMID: 23453514 DOI: 10.1016/j.ophtha.2012.12.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 12/06/2012] [Accepted: 12/06/2012] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To compare the clinical phenotype and detailed electroretinographic parameters in X-linked retinoschisis (XLRS). DESIGN Retrospective, comparative study. PARTICIPANTS Fifty-seven patients (aged 1-67 years) with molecularly confirmed XLRS were clinically ascertained. METHODS Pattern electroretinography (PERG) and full-field electroretinography (ERG), incorporating international standard recordings, were performed in 44 cases. Thirteen patients, mostly pediatric, were tested using a simplified ERG protocol. On-Off and S-cone ERGs were performed in most adults. Fundus autofluorescence (FAF) imaging and optical coherence tomography (OCT) were available in 17 and 21 cases, respectively. MAIN OUTCOME MEASURES The clinical and electrophysiologic data associated with different types of mutation in the RS1 gene. RESULTS Forty-three patients had missense changes (group A), and 14 patients had nonsense, splice-site, or frame-shifting mutations in the RS1 gene (group B). The mean best-corrected visual acuity was better in group A than in group B (0.34 and 0.21, respectively). Fundus examination revealed foveal schisis in approximately half of both groups. The bright-flash dark-adapted (DA) ERG (11.0 candela.sec.m(-2)) waveform was electronegative in 62% of group A eyes and 100% of group B eyes. The photopic 30-Hz flicker ERG was delayed in all group B eyes and all except 6 group A eyes. On-Off ERG b-waves were subnormal in 39% of group A and 89% of group B eyes; d-waves were delayed in 14 eyes (group A = 10, group B = 4). S-cone ERGs were abnormal in 50% of both groups. The PERG was abnormal in 88% of group A and 100% of group B eyes. A spoke-wheel pattern of high and low intensity was the most common FAF abnormality observed. The OCT showed intraretinal schitic cavities in the majority of eyes. CONCLUSIONS There is profound phenotypic variability in patients with XLRS. Most patients have DA bright-flash ERGs with a low b:a ratio in keeping with inner retinal dysfunction. Generalized cone system dysfunction is common and associated with an abnormal On-response and less frequent additional Off-response involvement. Nonsense, splice-site, or frame-shifting mutations in RS1 consistently caused electronegative bright-flash ERG, delayed flicker response, and abnormal PERG; missense mutations result in a wider range of ERG abnormalities.
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Affiliation(s)
- Ajoy Vincent
- Moorfields Eye Hospital, City Road, London, United Kingdom
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Molday RS, Kellner U, Weber BHF. X-linked juvenile retinoschisis: clinical diagnosis, genetic analysis, and molecular mechanisms. Prog Retin Eye Res 2012; 31:195-212. [PMID: 22245536 PMCID: PMC3334421 DOI: 10.1016/j.preteyeres.2011.12.002] [Citation(s) in RCA: 208] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 12/16/2011] [Accepted: 12/19/2011] [Indexed: 01/07/2023]
Abstract
X-linked juvenile retinoschisis (XLRS, MIM 312700) is a common early onset macular degeneration in males characterized by mild to severe loss in visual acuity, splitting of retinal layers, and a reduction in the b-wave of the electroretinogram (ERG). The RS1 gene (MIM 300839) associated with the disease encodes retinoschisin, a 224 amino acid protein containing a discoidin domain as the major structural unit, an N-terminal cleavable signal sequence, and regions responsible for subunit oligomerization. Retinoschisin is secreted from retinal cells as a disulphide-linked homo-octameric complex which binds to the surface of photoreceptors and bipolar cells to help maintain the integrity of the retina. Over 190 disease-causing mutations in the RS1 gene are known with most mutations occurring as non-synonymous changes in the discoidin domain. Cell expression studies have shown that disease-associated missense mutations in the discoidin domain cause severe protein misfolding and retention in the endoplasmic reticulum, mutations in the signal sequence result in aberrant protein synthesis, and mutations in regions flanking the discoidin domain cause defective disulphide-linked subunit assembly, all of which produce a non-functional protein. Knockout mice deficient in retinoschisin have been generated and shown to display most of the characteristic features found in XLRS patients. Recombinant adeno-associated virus (rAAV) mediated delivery of the normal RS1 gene to the retina of young knockout mice result in long-term retinoschisin expression and rescue of retinal structure and function providing a 'proof of concept' that gene therapy may be an effective treatment for XLRS.
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Affiliation(s)
- Robert S Molday
- Department of Biochemistry and Molecular Biology, Centre of Macular Research, University of British Columbia, 2350 Health Sciences Mall, Vancouver, B.C. V6T 1Z3, Canada.
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Duncan JL, Ratnam K, Birch DG, Sundquist SM, Lucero AS, Zhang Y, Meltzer M, Smaoui N, Roorda A. Abnormal cone structure in foveal schisis cavities in X-linked retinoschisis from mutations in exon 6 of the RS1 gene. Invest Ophthalmol Vis Sci 2011; 52:9614-23. [PMID: 22110067 DOI: 10.1167/iovs.11-8600] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To evaluate macular cone structure in patients with X-linked retinoschisis (XLRS) caused by mutations in exon 6 of the RS1 gene. METHODS High-resolution macular images were obtained with adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral domain optical coherence tomography (SD-OCT) in two patients with XLRS and 27 age-similar healthy subjects. Retinal structure was correlated with best-corrected visual acuity, kinetic and static perimetry, fundus-guided microperimetry, full-field electroretinography (ERG), and multifocal ERG. The six coding exons and the flanking intronic regions of the RS1 gene were sequenced in each patient. RESULTS Two unrelated males, ages 14 and 29, with visual acuity ranging from 20/32 to 20/63, had macular schisis with small relative central scotomas in each eye. The mixed scotopic ERG b-wave was reduced more than the a-wave. SD-OCT showed schisis cavities in the outer and inner nuclear and plexiform layers. Cone spacing was increased within the largest foveal schisis cavities but was normal elsewhere. In each patient, a mutation in exon 6 of the RS1 gene was identified and was predicted to change the amino acid sequence in the discoidin domain of the retinoschisin protein. CONCLUSIONS AOSLO images of two patients with molecularly characterized XLRS revealed increased cone spacing and abnormal packing in the macula of each patient, but cone coverage and function were near normal outside the central foveal schisis cavities. Although cone density is reduced, the preservation of wave-guiding cones at the fovea and eccentric macular regions has prognostic and therapeutic implications for XLRS patients with foveal schisis. (Clinical Trials.gov number, NCT00254605.).
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Affiliation(s)
- Jacque L Duncan
- Department of Ophthalmology, University of California at San Francisco, San Francisco, California 94143, USA.
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You J. Surgical treatment for complications of congenital retinoschisis. JOURNAL OF HUAZHONG UNIVERSITY OF SCIENCE AND TECHNOLOGY. MEDICAL SCIENCES = HUA ZHONG KE JI DA XUE XUE BAO. YI XUE YING DE WEN BAN = HUAZHONG KEJI DAXUE XUEBAO. YIXUE YINGDEWEN BAN 2011; 31:404. [PMID: 21671187 DOI: 10.1007/s11596-011-0390-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Indexed: 05/30/2023]
Abstract
This study examined the clinical features of complications of congenital retinoschisis and the clinical efficacy of vitreoretinal surgery in the treatment of these complications. The clinical efficacy of surgical treatments was retrospectively analyzed in 10 patients with congenital retinoschisis (10 eyes) complicated with rhegmatogenous retinal detachment (n=5), vitreous hemorrhage (n=2) and macula- involving schisis (n=1). All the patients suffered foveal and peripheral schisis. They were treated with scleral buckling (n=1) or vitrectomy (n=9). After the surgical treatment, the retina was reattached in patients with rhegmatogenous retinal detachment; the refractive media became transparent in those with vitreous hemorrhage; the visual acuity in 80% of patients was improved; no remarkable progression of schisis was found; no severe operative complications occurred. It was concluded that vitreoretinal surgery in the treatment of complications of congenital retinoschisis is safe and effective, and helps improve and maintain the visual function.
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Affiliation(s)
- Jiang You
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, 410011, China.
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Friedrich U, Stöhr H, Hilfinger D, Loenhardt T, Schachner M, Langmann T, Weber BH. The Na/K-ATPase is obligatory for membrane anchorage of retinoschisin, the protein involved in the pathogenesis of X-linked juvenile retinoschisis. Hum Mol Genet 2010; 20:1132-42. [DOI: 10.1093/hmg/ddq557] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Vijayasarathy C, Sui R, Zeng Y, Yang G, Xu F, Caruso RC, Lewis RA, Ziccardi L, Sieving PA. Molecular mechanisms leading to null-protein product from retinoschisin (RS1) signal-sequence mutants in X-linked retinoschisis (XLRS) disease. Hum Mutat 2010; 31:1251-60. [PMID: 20809529 DOI: 10.1002/humu.21350] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Retinoschisin (RS1) is a cell-surface adhesion molecule expressed by photoreceptor and bipolar cells of the retina. The 24-kDa protein encodes two conserved sequence motifs: the initial signal sequence targets the protein for secretion while the larger discoidin domain is implicated in cell adhesion. RS1 helps to maintain the structural organization of the retinal cell layers and promotes visual signal transduction. RS1 gene mutations cause X-linked retinoschisis disease (XLRS) in males, characterized by early-onset central vision loss. We analyzed the biochemical consequences of several RS1 signal-sequence mutants (c.1A>T, c.35T>A, c.38T>C, and c.52G>A) found in our subjects. Expression analysis in COS-7 cells demonstrates that these mutations affect RS1 biosynthesis and result in an RS1 null phenotype by several different mechanisms. By comparison, discoidin-domain mutations generally lead to nonfunctional conformational variants that remain trapped inside the cell. XLRS disease has a broad heterogeneity in general, but subjects with the RS1 null-protein signal-sequence mutations are on the more severe end of the clinical phenotype. Results from the signal-sequence mutants are discussed in the context of the discoidin-domain mutations, clinical phenotypes, genotype-phenotype correlations, and implications for RS1 gene replacement therapy.
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Affiliation(s)
- Camasamudram Vijayasarathy
- Section on Translational Research for Retinal and Macular Degeneration, National Institute on Deafness and Other Communication Disorders, National Institutes of Health (NIH), Bethesda, Maryland 20892, USA
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Kjellström S, Vijayasarathy C, Ponjavic V, Sieving PA, Andréasson S. Long-term 12 year follow-up of X-linked congenital retinoschisis. Ophthalmic Genet 2010; 31:114-25. [PMID: 20569020 DOI: 10.3109/13816810.2010.482555] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To investigate the retinal structure and function during the progression of X-linked retinoschisis (XLRS) from childhood to adulthood. METHODS Ten patients clinically diagnosed with XLRS were investigated at 6-15 years of age (mean age 9 years) with a follow-up 8 to 14 years later (mean 12 years). The patients underwent regular ophthalmic examination as well as testing of best corrected visual acuity (BCVA), visual field (VF) and assessment of full-field electroretinography (ERG) during their first visit. During the follow-up, the same clinical protocols were repeated. In addition, macular structure and function was examined with multifocal electroretinography (mfERG) and optical coherence tomography (OCT). The patients were 18-25 years of age (mean age 21 years) at the follow-up examination. All exons and exon-intron boundaries of RS1-gene were sequenced for gene mutations in 9 out of the 10 patients. RESULTS Best corrected VA and VF were stable during this follow-up period. No significant progression in cone or rod function could be measured by full-field ERG. Multifocal electroretinography and OCT demonstrated a wide heterogeneity of macular changes in retinal structure and function at the time of follow-up visit. Three different mutations were detected in these nine patients, including a known nonsense mutation in exon 3, a novel insertion in exon 5 and an intronic mutation at 5' splice site of intron 3. CONCLUSIONS Clinical follow-up (mean 12 years) of ten young XLRS patients (mean age of 9 years) with a typical congenital retinoschisis phenotype revealed no significant decline in retinal function during this time period. MfERG and OCT demonstrated a wide variety of macular changes including structure and dysfunction. The XLRS disease was relatively stable during this period of observation and would afford opportunity for therapy studies to judge benefit against baseline and against the fellow eye.
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Atchaneeyasakul LO, Trinavarat A, Pituksung A, Jinda W, Thongnoppakhun W, Limwongse C. Mutations in the XLRS1 gene in Thai families with X-linked juvenile retinoschisis. Jpn J Ophthalmol 2010; 54:89-93. [PMID: 20151283 DOI: 10.1007/s10384-009-0748-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 09/03/2009] [Indexed: 11/28/2022]
Abstract
PURPOSE To identify genetic mutations of the XLRS1 gene and to describe the ocular phenotypes in two unrelated Thai patients with X-linked juvenile retinoschisis. METHODS Ophthalmic examination, including best-corrected visual acuity and fundus examination and photography, was performed in all participants. Electroretinography (ERG) and optical coherence tomography were performed when possible. All six exons of the XLRS1 gene were amplified, and mutation screening was determined by denaturing high-performance liquid chromatography and DNA sequencing. RESULTS Two point mutations were identified, a novel missense mutation c.378A > G (p.D126G) in exon 5 and a reported mutation c.637C > T (p.R213W) in exon 6. The first proband with the p.D126G mutation developed vitreous hemorrhage in both eyes at age 7 months. Foveal and peripheral schisis with several inner layer holes were detected in both eyes. The second proband with the p.R213W mutation developed slightly blurred vision at age 10 years. Fundus examination showed numerous fine white dots at the macula without foveal or peripheral schisis. Electronegative ERG results were documented in both probands. CONCLUSIONS A novel p.D126G mutation appeared to be associated with a severe phenotype with vitreous hemorrhage developing in infancy. Both intra- and interfamilial clinical variabilities were recognized in our patients.
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Abstract
BACKGROUND Cone dystrophies present with highly variable clinical findings and often limited retinal changes, which may lead to misdiagnosis. The purpose of the present review of the clinical presentation and diagnosis of cone dystrophies is to provide guidelines for improved patient care. METHODS A literature search and evaluation of the clinical findings were carried out in 450 patients with cone dystrophy examined between 1986 and 2008. RESULTS Characteristic signs are loss of visual acuity, photophobia and central scotoma. The diagnosis of cone dystrophy is determined by a full-field electroretinogram (ERG). Fundus and near-infrared autofluorescence as well as optical coherence tomography allow detection of retinal structural abnormalities even when findings from ophthalmoscopy are normal. CONCLUSION The diagnosis of cone dystrophy is difficult due to unspecific subjective symptoms and absence of characteristic ophthalmoscopic findings. The differential diagnosis of unexplained visual loss should include cone dystrophy and requires either a full-field or multifocal ERG.
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Genead MA, Pasadhika S, Fishman GA. Retinal nerve fibre layer thickness analysis in X-linked retinoschisis using Fourier-domain OCT. Eye (Lond) 2009; 23:1019-27. [PMID: 19373267 PMCID: PMC2865150 DOI: 10.1038/eye.2009.53] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose 19 To evaluate the presence of retinal nerve fiber layer (RNFL) defects in patients with XLRS using high speed, high resolution, Fourier domain OCT (FD-OCT). Methods Twenty four patients with XLRS seen by the authors were enrolled in the study. All patients underwent a complete eye examination. FD-OCT was performed using Optovue technology. A quadrant of the RNFL was considered to be thinned if at least 2 of the 4 segments in the quadrant were reduced in thickness. Results The average age of the 24 patients in the study was 28.8 years ± 14.7 years. Thinning of the RNFL in 1 quadrant was seen in 10 patients (41.7%), and thinning in 2 or more quadrants was seen in 8 patients (33.3%). Thinning in the inferior quadrant was most commonly seen and was observed in 12 patients (50%), followed by the temporal quadrant in 8 patients (33.3%), nasal quadrant in 4 patients (16.7%), and the superior quadrant in 4 patients (16.7%). Conclusions Among our 24 patients with XLRS, 15 patients (62.5%) showed a thinning of the RNFL in one or more quadrants in at least one eye and 9 patients (37.5%) in both eyes. The use of high speed, high resolution FD-OCT may be useful to determine the presence of possible changes in RNFL thickness in patients with XLRS. Reductions in RNFL thickness in such patients could be relevant in their selection for future therapeutic trials.
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Affiliation(s)
- M A Genead
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
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Kellner U. Imaging and the perspective of clinical electrophysiology. Doc Ophthalmol 2007; 116:75-7. [PMID: 18092186 DOI: 10.1007/s10633-007-9106-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Accepted: 12/05/2007] [Indexed: 10/22/2022]
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