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Chan J, Holdstock J, Shovelton J, Reid J, Speight G, Molha D, Pullabhatla V, Carpenter S, Uddin E, Washio T, Sato H, Izumi Y, Watanabe R, Niiro H, Fukushima Y, Ashida N, Hirose T, Maeda A. Clinical and analytical validation of an 82-gene comprehensive genome-profiling panel for identifying and interpreting variants responsible for inherited retinal dystrophies. PLoS One 2024; 19:e0305422. [PMID: 38870140 PMCID: PMC11175448 DOI: 10.1371/journal.pone.0305422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/30/2024] [Indexed: 06/15/2024] Open
Abstract
Inherited retinal dystrophies comprise a clinically complex and heterogenous group of diseases characterized by visual impairment due to pathogenic variants of over 300 different genes. Accurately identifying the causative gene and associated variant is crucial for the definitive diagnosis and subsequent selection of precise treatments. Consequently, well-validated genetic tests are required in the clinical practice. Here, we report the analytical and clinical validation of a next-generation sequencing targeted gene panel, the PrismGuide IRD Panel System. This system enables comprehensive genome profiling of 82 genes related to inherited retinal dystrophies. The PrismGuide IRD Panel System demonstrated 100% (n = 43) concordance with Sanger sequencing in detecting single-nucleotide variants, small insertions, and small deletions in the target genes and also in assessing their zygosity. It also identified copy-number loss in four out of five cases. When assessing precision, we evaluated the reproducibility of variant detection with 2,160 variants in 144 replicates and found 100% agreement in terms of single-nucleotide variants (n = 1,584) and small insertions and deletions (n = 576). Furthermore, the PrismGuide IRD Panel System generated sufficient read depth for variant calls across the purine-rich and highly repetitive open-reading frame 15 region of RPGR and detected all five variants tested. These results show that the PrismGuide IRD Panel System can accurately and consistently detect single-nucleotide variants and small insertions and deletions. Thus, the PrismGuide IRD Panel System could serve as useful tool that is applicable in clinical practice for identifying the causative genes based on the detection and interpretation of variants in patients with inherited retinal dystrophies and can contribute to a precise molecular diagnosis and targeted treatments.
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Affiliation(s)
- Jacqueline Chan
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Jolyon Holdstock
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - John Shovelton
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - James Reid
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Graham Speight
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Duarte Molha
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Venu Pullabhatla
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Stephanie Carpenter
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Ezam Uddin
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Takanori Washio
- Life Innovation Center, Riken Genesis Co. LTD, Kawasaki, Kanagawa, Japan
- Division of Clinical Cancer Genomics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan
| | - Hiroko Sato
- Life Innovation Center, Riken Genesis Co. LTD, Kawasaki, Kanagawa, Japan
| | - Yuuki Izumi
- Technology Innovation, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Reiko Watanabe
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Hayato Niiro
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | | | - Naoko Ashida
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Takashi Hirose
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Akiko Maeda
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan
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Georgiou M, Robson AG, Uwaydat SH, Ji MH, Shakarchi AF, Pontikos N, Mahroo OA, Cheetham ME, Webster AR, Hardcastle AJ, Michaelides M. RP2-Associated X-linked Retinopathy: Clinical Findings, Molecular Genetics, and Natural History in a Large Cohort of Female Carriers. Am J Ophthalmol 2024; 261:112-120. [PMID: 37977507 PMCID: PMC11139645 DOI: 10.1016/j.ajo.2023.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 10/25/2023] [Accepted: 11/03/2023] [Indexed: 11/19/2023]
Abstract
PURPOSE RP2-associated retinopathy typically causes severe early onset retinitis pigmentosa (RP) in affected males. However, there is a scarcity of reports describing the clinical phenotype of female carriers. We tested the hypothesis that RP2 variants manifest in female carriers with a range of functional and anatomic characteristics. DESIGN Retrospective case series. METHODS Females with disease-causing variants in RP2 were identified from investigation of pedigrees affected by RP2 retinopathy. All case notes and results of molecular genetic testing, retinal imaging (fundus autofluorescence imaging, optical coherence tomography (OCT)), and electrophysiology were reviewed. RESULTS Forty pedigrees were investigated. Twenty-nine pedigrees had obligate carriers or molecularly confirmed female members with recorded relevant history and/or examination. For 8 pedigrees, data were available only from history, with patients reporting affected female relatives with RP in 4 cases and unaffected female relatives in the other 4 cases. Twenty-seven females from 21 pedigrees were examined by a retinal genetics specialist. Twenty-three patients (85%) reported no complaints and had normal vision and 4 patients had RP-associated complaints (15%). Eight patients had normal fundus examination (30%), 10 had a tapetal-like reflex (TLR; 37%), 5 had scattered peripheral pigmentation (19%), and the 4 symptomatic patients had fundus findings compatible with RP (15%). All asymptomatic patients with normal fundus, TLR, or asymptomatic pigmentary changes had a continuous ellipsoid zone on OCT when available. The electroretinograms revealed mild to severe photoreceptor dysfunction in 9 of 11 subjects, often asymmetrical, including 5 with pattern electroretinogram evidence of symmetrical (n = 4) or unilateral (n = 1 subject) macular dysfunction. CONCLUSIONS Most carriers were asymptomatic, exhibiting subclinical characteristics such as TLR and pigmentary changes. However, female carriers of RP2 variants can manifest RP. Family history of affected females with RP does not exclude X-linked disease. The phenotypic spectrum as described herein has prognostic and counselling implications for RP2 carriers and patients.
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Affiliation(s)
- Michalis Georgiou
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom; Jones Eye Institute (M.G., S.H.U., M.H.J., A.F.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Anthony G Robson
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Sami H Uwaydat
- Jones Eye Institute (M.G., S.H.U., M.H.J., A.F.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Marco H Ji
- Jones Eye Institute (M.G., S.H.U., M.H.J., A.F.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Ahmed F Shakarchi
- Jones Eye Institute (M.G., S.H.U., M.H.J., A.F.S.), University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Nikolas Pontikos
- University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Omar A Mahroo
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Michael E Cheetham
- University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Andrew R Webster
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Alison J Hardcastle
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom
| | - Michel Michaelides
- From the Moorfields Eye Hospital (M.G., A.G.R., N.P., O.A.M., A.R.W., M.M.), London, United Kingdeom; University College London Institute of Ophthalmology (M.G., A.G.R., N.P., O.A.M., M.E.C., A.R.W., A.J.H., M.M.), University College London, London, United Kingdom.
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Baz-Redón N, Sánchez-Bellver L, Fernández-Cancio M, Rovira-Amigo S, Burgoyne T, Ranjit R, Aquino V, Toro-Barrios N, Carmona R, Polverino E, Cols M, Moreno-Galdó A, Camats-Tarruella N, Marfany G. Primary Ciliary Dyskinesia and Retinitis Pigmentosa: Novel RPGR Variant and Possible Modifier Gene. Cells 2024; 13:524. [PMID: 38534367 DOI: 10.3390/cells13060524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 03/09/2024] [Accepted: 03/13/2024] [Indexed: 03/28/2024] Open
Abstract
We report a novel RPGR missense variant co-segregated with a familial X-linked retinitis pigmentosa (XLRP) case. The brothers were hemizygous for this variant, but only the proband presented with primary ciliary dyskinesia (PCD). Thus, we aimed to elucidate the role of the RPGR variant and other modifier genes in the phenotypic variability observed in the family and its impact on motile cilia. The pathogenicity of the variant on the RPGR protein was evaluated by in vitro studies transiently transfecting the mutated RPGR gene, and immunofluorescence analysis on nasal brushing samples. Whole-exome sequencing was conducted to identify potential modifier variants. In vitro studies showed that the mutated RPGR protein could not localise to the cilium and impaired cilium formation. Accordingly, RPGR was abnormally distributed in the siblings' nasal brushing samples. In addition, a missense variant in CEP290 was identified. The concurrent RPGR variant influenced ciliary mislocalisation of the protein. We provide a comprehensive characterisation of motile cilia in this XLRP family, with only the proband presenting PCD symptoms. The variant's pathogenicity was confirmed, although it alone does not explain the respiratory symptoms. Finally, the CEP290 gene may be a potential modifier for respiratory symptoms in patients with RPGR mutations.
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Affiliation(s)
- Noelia Baz-Redón
- Growth and Development Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Laura Sánchez-Bellver
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Mónica Fernández-Cancio
- Growth and Development Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Sandra Rovira-Amigo
- Growth and Development Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Department of Paediatrics, Vall d'Hebron Hospital Universitari, Vall d'Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain
| | - Thomas Burgoyne
- Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, London SW3 6NP, UK
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Rai Ranjit
- Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, London SW3 6NP, UK
| | - Virginia Aquino
- Plataforma Andaluza de Medicina Computacional, Fundación Pública Andaluza Progreso y Salud, 41092 Sevilla, Spain
| | - Noemí Toro-Barrios
- Plataforma Andaluza de Medicina Computacional, Fundación Pública Andaluza Progreso y Salud, 41092 Sevilla, Spain
| | - Rosario Carmona
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Plataforma Andaluza de Medicina Computacional, Fundación Pública Andaluza Progreso y Salud, 41092 Sevilla, Spain
| | - Eva Polverino
- Pneumology Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Pneumology Department, Vall d'Hebron Hospital Universitari, Vall d'Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Maria Cols
- Paediatric Pulmonology Department and Cystic Fibrosis Unit, Hospital Sant Joan de Déu, 08950 Esplugues de Llobregat, Spain
| | - Antonio Moreno-Galdó
- Growth and Development Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Department of Paediatrics, Vall d'Hebron Hospital Universitari, Vall d'Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain
- Department of Paediatrics, Obstetrics, Gynecology, Preventive Medicine and Public Health, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Núria Camats-Tarruella
- Growth and Development Research Group, Vall d'Hebron Research Institute (VHIR), Hospital Universitari Vall d'Hebron, 08035 Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Gemma Marfany
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, 28029 Madrid, Spain
- Departament de Genètica, Microbiologia i Estadística, Universitat de Barcelona, 08028 Barcelona, Spain
- Institute of Biomedicine (IBUB-IRSJD), Universitat de Barcelona, 08028 Barcelona, Spain
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McDonald A, Wijnholds J. Retinal Ciliopathies and Potential Gene Therapies: A Focus on Human iPSC-Derived Organoid Models. Int J Mol Sci 2024; 25:2887. [PMID: 38474133 DOI: 10.3390/ijms25052887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
The human photoreceptor function is dependent on a highly specialised cilium. Perturbation of cilial function can often lead to death of the photoreceptor and loss of vision. Retinal ciliopathies are a genetically diverse range of inherited retinal disorders affecting aspects of the photoreceptor cilium. Despite advances in the understanding of retinal ciliopathies utilising animal disease models, they can often lack the ability to accurately mimic the observed patient phenotype, possibly due to structural and functional deviations from the human retina. Human-induced pluripotent stem cells (hiPSCs) can be utilised to generate an alternative disease model, the 3D retinal organoid, which contains all major retinal cell types including photoreceptors complete with cilial structures. These retinal organoids facilitate the study of disease mechanisms and potential therapies in a human-derived system. Three-dimensional retinal organoids are still a developing technology, and despite impressive progress, several limitations remain. This review will discuss the state of hiPSC-derived retinal organoid technology for accurately modelling prominent retinal ciliopathies related to genes, including RPGR, CEP290, MYO7A, and USH2A. Additionally, we will discuss the development of novel gene therapy approaches targeting retinal ciliopathies, including the delivery of large genes and gene-editing techniques.
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Affiliation(s)
- Andrew McDonald
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZC Leiden, The Netherlands
- Netherlands Institute of Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), 1105 BA Amsterdam, The Netherlands
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5
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Pantrangi M, Rath J, Kaetterhenry N, Branham K, Talsness D, Weber JL. Clinical sequencing of the retinitis pigmentosa gene RPGR in over 1,000 cases of vision loss. Mol Vis 2024; 30:49-57. [PMID: 38586605 PMCID: PMC10994678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 02/17/2024] [Indexed: 04/09/2024] Open
Abstract
RPGR pathogenic variants are the major cause of X-linked retinitis pigmentosa. Here, we report the results from 1,033 clinical DNA tests that included sequencing of RPGR. A total of 184 RPGR variants were identified: 78 pathogenic or likely pathogenic, 14 uncertain, and 92 likely benign or benign. Among the pathogenic and likely pathogenic variants, 23 were novel, and most were frameshift or nonsense mutations (87%) and enriched (67%) in RPGR exon 15 (ORF15). Identical pathogenic variants found in different families were largely on different haplotype backgrounds, indicating relatively frequent, recurrent RPGR mutations. None of the 16 mother/affected son pairs showed de novo mutations; all 16 mothers were heterozygous for the pathogenic variant. These last two observations support the occurrence of most RPGR mutations in the male germline.
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Affiliation(s)
- Madhulatha Pantrangi
- PreventionGenetics, part of Exact Sciences, Marshfield, WI
- Weill Cornell Medicine, Department of Pathology and Laboratory Medicine, New York, NY
| | - Julie Rath
- PreventionGenetics, part of Exact Sciences, Marshfield, WI
| | | | - Kari Branham
- University of Michigan, Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, Ann Arbor, MI
| | - Dana Talsness
- PreventionGenetics, part of Exact Sciences, Marshfield, WI
| | - James L Weber
- PreventionGenetics, part of Exact Sciences, Marshfield, WI
- University of Wisconsin, School of Medicine and Public Health, Department of Pediatrics, Madison, WI
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6
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He X, Fu Y, Ma L, Yao Y, Ge S, Yang Z, Fan X. AAV for Gene Therapy in Ocular Diseases: Progress and Prospects. RESEARCH (WASHINGTON, D.C.) 2023; 6:0291. [PMID: 38188726 PMCID: PMC10768554 DOI: 10.34133/research.0291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 11/27/2023] [Indexed: 01/09/2024]
Abstract
Owing to the promising therapeutic effect and one-time treatment advantage, gene therapy may completely change the management of eye diseases, especially retinal diseases. Adeno-associated virus (AAV) is considered one of the most promising viral gene delivery tools because it can infect various types of tissues and is considered as a relatively safe gene delivery vector. The eye is one of the most popular organs for gene therapy, since its limited volume is suitable for small doses of AAV stably transduction. Recently, an increasing number of clinical trials of AAV-mediated gene therapy are underway. This review summarizes the biological functions of AAV and its application in the treatment of various ocular diseases, as well as the characteristics of different AAV delivery routes in clinical applications. Here, the latest research progresses in AAV-mediated gene editing and silencing strategies to modify that the genetic ocular diseases are systematically outlined, especially by base editing and prime editing. We discuss the progress of AAV in ocular optogenetic therapy. We also summarize the application of AAV-mediated gene therapy in animal models and the difficulties in its clinical transformation.
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Affiliation(s)
- Xiaoyu He
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yidian Fu
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Liang Ma
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yizheng Yao
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University; Clinical Research Center of Neurological Disease,
The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Shengfang Ge
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Zhi Yang
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Xianqun Fan
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
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7
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Nowomiejska K, Baltaziak K, Całka P, Ciesielka M, Teresiński G, Rejdak R. Identification of the RPGR Gene Pathogenic Variants in a Cohort of Polish Male Patients with Retinitis Pigmentosa Phenotype. Genes (Basel) 2023; 14:1950. [PMID: 37895299 PMCID: PMC10606843 DOI: 10.3390/genes14101950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/13/2023] [Accepted: 10/15/2023] [Indexed: 10/29/2023] Open
Abstract
The goal of the study was to explore the spectrum of pathogenic variants in the RPGR gene in a group of male Polish patients with a retinitis pigmentosa (RP) phenotype. A total of 45 male index patients, including twins, being members of 44 families, were screened for pathogenic variants in the RPGR gene via the direct sequencing of PCR-amplified genomic DNA and underwent a comprehensive ophthalmological examination in one center located in Poland. A total of two pathogenic and five likely pathogenic variants in eight patients (18%) were detected in the studied cohort. Of these, five variants were novel, and five disease-causing variants (71%) were identified within the ORF15 mutational hotspot of the RPGR gene. The median age of onset of the disease was 10 years (range 6-14 years), the median age during the examination was 30 years (range 20-47 years), and the median visual acuity was 0.4 (range 0.01-0.7). The majority of patients had middle constriction of the visual field and thinning of the central foveal thickness. Dizygotic twins bearing the same hemizygous mutation showed a different retinal phenotype in regard to the severity of the symptoms. This is the first RPGR mutation screening in Poland showing a prevalence of 18% of RPGR pathogenic mutations and likely pathogenic variants in the studied cohort of male patients with an RP phenotype.
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Affiliation(s)
- Katarzyna Nowomiejska
- Chair and Department of General and Pediatric Ophthalmology, Medical University of Lublin, 20-059 Lublin, Poland; (K.B.); (R.R.)
| | - Katarzyna Baltaziak
- Chair and Department of General and Pediatric Ophthalmology, Medical University of Lublin, 20-059 Lublin, Poland; (K.B.); (R.R.)
| | - Paulina Całka
- Department of Forensic Medicine, Medical University of Lublin, 20-059 Lublin, Poland; (P.C.); (M.C.); (G.T.)
| | - Marzanna Ciesielka
- Department of Forensic Medicine, Medical University of Lublin, 20-059 Lublin, Poland; (P.C.); (M.C.); (G.T.)
| | - Grzegorz Teresiński
- Department of Forensic Medicine, Medical University of Lublin, 20-059 Lublin, Poland; (P.C.); (M.C.); (G.T.)
| | - Robert Rejdak
- Chair and Department of General and Pediatric Ophthalmology, Medical University of Lublin, 20-059 Lublin, Poland; (K.B.); (R.R.)
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8
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Wongchaisuwat N, Amato A, Lamborn AE, Yang P, Everett L, Pennesi ME. Retinitis pigmentosa GTPase regulator-related retinopathy and gene therapy. Saudi J Ophthalmol 2023; 37:276-286. [PMID: 38155670 PMCID: PMC10752277 DOI: 10.4103/sjopt.sjopt_168_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/14/2023] [Accepted: 08/16/2023] [Indexed: 12/30/2023] Open
Abstract
Retinitis pigmentosa GTPase regulator (RPGR)-related retinopathy is a retinal dystrophy inherited in a X-linked recessive manner that typically causes progressive visual loss starting in childhood with severe visual impairment by the fourth decade of life. It manifests as an early onset and severe form of retinitis pigmentosa. There are currently no effective treatments for RPGR-related retinopathy; however, there are multiple clinical trials in progress exploring gene augmentation therapy aimed at slowing down or halting the progression of disease and possibly restoring visual function. This review focuses on the molecular biology, clinical manifestations, and the recent progress of gene therapy clinical trials.
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Affiliation(s)
- Nida Wongchaisuwat
- Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Alessia Amato
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Andrew E. Lamborn
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Lesley Everett
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon, USA
| | - Mark E. Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon, USA
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Gocuk SA, Jolly JK, Edwards TL, Ayton LN. Female carriers of X-linked inherited retinal diseases - Genetics, diagnosis, and potential therapies. Prog Retin Eye Res 2023; 96:101190. [PMID: 37406879 DOI: 10.1016/j.preteyeres.2023.101190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 07/07/2023]
Abstract
Inherited retinal diseases (IRDs) are a group of heterogeneous conditions that cause progressive vision loss, typically due to monogenic mutations. Female carriers of X-linked IRDs have a single copy of the disease-causing gene, and therefore, may exhibit variable clinical signs that vary from near normal retina to severe disease and vision loss. The relationships between individual genetic mutations and disease severity in X-linked carriers requires further study. This review summarises the current literature surrounding the spectrum of disease seen in female carriers of choroideremia and X-linked retinitis pigmentosa. Various classification systems are contrasted to accurately grade retinal disease. Furthermore, genetic mechanisms at the early embryonic stage are explored to potentially explain the variability of disease seen in female carriers. Future research in this area will provide insight into the association between genotype and retinal phenotypes of female carriers, which will guide in the management of these patients. This review acknowledges the importance of identifying which patients may be at high risk of developing severe symptoms, and therefore should be considered for emerging treatments, such as retinal gene therapy.
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Affiliation(s)
- Sena A Gocuk
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Victoria, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jasleen K Jolly
- Vision and Eye Research Institute, Anglia Ruskin University, Cambridge, UK
| | - Thomas L Edwards
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia
| | - Lauren N Ayton
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Victoria, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia.
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10
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Kelley RA, Wu Z. Utilization of the retinal organoid model to evaluate the feasibility of genetic strategies to ameliorate retinal disease(s). Vision Res 2023; 210:108269. [PMID: 37295270 DOI: 10.1016/j.visres.2023.108269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 06/12/2023]
Abstract
Organoid models have quickly become a popular research tool to evaluate novel therapeutics on 3-D recapitulated tissue. This has enabled researchers to use physiologically relevant human tissue in vitro to augment the standard use of immortalized cells and animal models. Organoids can also provide a model when an engineered animal cannot recreate a specific disease phenotype. In particular, the retinal research field has taken advantage of this burgeoning technology to provide insight into inherited retinal disease(s) mechanisms and therapeutic intervention to ameliorate their effects. In this review we will discuss the use of both wild-type and patient-specific retinal organoids to further gene therapy research that could potentially prevent retinal disease(s) progression. Furthermore, we will discuss the pitfalls of current retinal organoid technology and present potential solutions that could overcome these hurdles in the near future.
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Affiliation(s)
- Ryan A Kelley
- PTC Therapeutics, 100 Corporate Ct #2400, South Plainfield, NJ 07080, USA.
| | - Zhijian Wu
- PTC Therapeutics, 100 Corporate Ct #2400, South Plainfield, NJ 07080, USA
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11
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Yahya S, Watson CM, Carr I, McKibbin M, Crinnion LA, Taylor M, Bonin H, Fletcher T, El-Asrag ME, Ali M, Toomes C, Inglehearn CF. Long-Read Nanopore Sequencing of RPGR ORF15 is Enhanced Following DNase I Treatment of MinION Flow Cells. Mol Diagn Ther 2023; 27:525-535. [PMID: 37284979 PMCID: PMC10299921 DOI: 10.1007/s40291-023-00656-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2023] [Indexed: 06/08/2023]
Abstract
INTRODUCTION RPGR ORF15 is an exon present almost exclusively in the retinal transcript of RPGR. It is purine-rich, repetitive and notoriously hard to sequence, but is a hotspot for mutations causing X-linked retinitis pigmentosa. METHODS Long-read nanopore sequencing on MinION and Flongle flow cells was used to sequence RPGR ORF15 in genomic DNA from patients with inherited retinal dystrophy. A flow cell wash kit was used on a MinION flow cell to increase yield. Findings were confirmed by PacBio SMRT long-read sequencing. RESULTS We showed that long-read nanopore sequencing successfully reads through a 2 kb PCR-amplified fragment containing ORF15. We generated reads of sufficient quality and cumulative read-depth to detect pathogenic RP-causing variants. However, we observed that this G-rich, repetitive DNA segment rapidly blocks the available pores, resulting in sequence yields less than 5% of the expected output. This limited the extent to which samples could be pooled, increasing cost. We tested the utility of a MinION wash kit containing DNase I to digest DNA fragments remaining on the flow cell, regenerating the pores. Use of the DNase I treatment allowed repeated re-loading, increasing the sequence reads obtained. Our customised workflow was used to screen pooled amplification products from previously unsolved inherited retinal disease (IRD) in patients, identifying two new cases with pathogenic ORF15 variants. DISCUSSION We report the novel finding that long-read nanopore sequencing can read through RPGR-ORF15, a DNA sequence not captured by short-read next-generation sequencing (NGS), but with a more reduced yield. Use of a flow cell wash kit containing DNase I unblocks the pores, allowing reloading of further library aliquots over a 72-h period, increasing yield. The workflow we describe provides a novel solution to the need for a rapid, robust, scalable, cost-effective ORF15 screening protocol.
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Affiliation(s)
- Samar Yahya
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Medical Genetics, School of Medicine, King Abdulaziz University, Rabigh, Kingdom of Saudi Arabia
| | - Christopher M Watson
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- North East and Yorkshire Genomic Laboratory Hub, Central Lab, St. James's University Hospital, Leeds, UK
| | - Ian Carr
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Martin McKibbin
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Ophthalmology, St. James's University Hospital, Leeds, UK
| | - Laura A Crinnion
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Morag Taylor
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Hope Bonin
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester, UK
| | - Tracy Fletcher
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester, UK
| | - Mohammed E El-Asrag
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Zoology, Faculty of Science, Benha University, Banha, Egypt
- Institute of Cancer and Genomic Science, University of Birmingham, Birmingham, UK
| | - Manir Ali
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Carmel Toomes
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Chris F Inglehearn
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK.
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Tran M, Kolesnikova M, Kim AH, Kowal T, Ning K, Mahajan VB, Tsang SH, Sun Y. Clinical characteristics of high myopia in female carriers of pathogenic RPGR mutations: a case series and review of the literature. Ophthalmic Genet 2023; 44:295-303. [PMID: 36017691 PMCID: PMC9968361 DOI: 10.1080/13816810.2022.2113544] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 07/24/2022] [Accepted: 08/01/2022] [Indexed: 10/15/2022]
Abstract
BACKGROUND RPGR mutations are the most common cause of X-linked retinitis pigmentosa (XLRP). High myopia has been described as a very frequent feature among affected female carriers of XLRP. However, the clinical phenotype of female patients presenting with X-linked RPGR-related high myopia has not been well described. MATERIALS AND METHODS Retrospective case series of four female patients with RPGR mutations and a diagnosis of high myopia, who presented to two academic eye centers. Clinical data, including age, family history, visual acuity, refractive error, dilated fundus exam, fundus photography, optical coherence tomography, electroretinography, and results of genetic testing, were collected. RESULTS Three RPGR variants identified in the present study have not been previously associated with myopia in female carriers. One variant (c.2405_2406delAG, p.Glu802Glyfs *32) has been previously associated with a myopic phenotype in a female patient. Patients became symptomatic between the first and sixth decades of life. Myopia-associated tilted optic discs and posterior staphyloma were present in all patients. Two patients presented with intraretinal migration of the retinal pigment epithelium. CONCLUSION RPGR-related high myopia has been associated with mutations in exons 1-14 and ORF15 in heterozygous females. There is a wide range of visual function among carriers. Although the exact mechanism of RPGR-related high myopia is still unclear, continued molecular diagnosis and description of phenotypes remain a crucial step in understanding the impact of RPGR mutations on visual function in female XLRP carriers.
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Affiliation(s)
- Matthew Tran
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
- University of Nevada, Reno School of Medicine, Reno, Nevada, USA
| | - Masha Kolesnikova
- Jonas Children’s Vision Care, Department of Ophthalmology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Angela H. Kim
- Jonas Children’s Vision Care, Department of Ophthalmology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Tia Kowal
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
- Palo Alto Veterans Administration, Palo Alto, California, USA
| | - Ke Ning
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
| | - Vinit B. Mahajan
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
- Palo Alto Veterans Administration, Palo Alto, California, USA
| | - Stephen H. Tsang
- Jonas Children’s Vision Care, Department of Ophthalmology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
- Edward S. Harkness Eye Institute, New York Presbyterian Hospital, New York, New York, USA
| | - Yang Sun
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
- Palo Alto Veterans Administration, Palo Alto, California, USA
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13
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Birch DG, Cheetham JK, Daiger SP, Hoyng C, Kay C, MacDonald IM, Pennesi ME, Sullivan LS. Overcoming the Challenges to Clinical Development of X-Linked Retinitis Pigmentosa Therapies: Proceedings of an Expert Panel. Transl Vis Sci Technol 2023; 12:5. [PMID: 37294701 PMCID: PMC10270308 DOI: 10.1167/tvst.12.6.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 04/24/2023] [Indexed: 06/11/2023] Open
Abstract
X-linked retinitis pigmentosa (XLRP) is a rare inherited retinal disease manifesting as impaired night vision and peripheral vision loss that progresses to legal blindness. Although several trials of ocular gene therapy for XLRP have been conducted or are in progress, there is currently no approved treatment. In July 2022, the Foundation Fighting Blindness convened an expert panel to examine relevant research and make recommendations for overcoming the challenges and capitalizing on the opportunities in conducting clinical trials of RPGR-targeted therapy for XLRP. Data presented concerned RPGR structure and mutation types known to cause XLRP, RPGR mutation-associated retinal phenotype diversity, patterns in genotype/phenotype relationships, disease onset and progression from natural history studies, and the various functional and structural tests used to monitor disease progression. Panel recommendations include considerations, such as genetic screening and other factors that can impact clinical trial inclusion criteria, the influence of age on defining and stratifying participant cohorts, the importance of conducting natural history studies early in clinical development programs, and the merits and drawbacks of available tests for measuring treatment outcomes. We recognize the need to work with regulators to adopt clinically meaningful end points that would best determine the efficacy of a trial. Given the promise of RPGR-targeted gene therapy for XLRP and the difficulties encountered in phase III clinical trials to date, we hope these recommendations will help speed progress to finding a cure. Translational Relevance Examination of relevant data and recommendations for the successful clinical development of gene therapies for RPGR-associated XLRP.
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Affiliation(s)
| | | | - Stephen P. Daiger
- Human Genetics Center, School of Public Health, University of Texas Health Science Center, Houston, TX, USA
| | - Carel Hoyng
- Radboud University, Nijmegen, The Netherlands
| | | | | | - Mark E. Pennesi
- Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Lori S. Sullivan
- Human Genetics Center, School of Public Health, University of Texas Health Science Center, Houston, TX, USA
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14
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Schlottmann PG, Luna JD, Labat N, Yadarola MB, Bainttein S, Esposito E, Ibañez A, Barbaro EI, Álvarez Mendiara A, Picotti CP, Chirino Misisian A, Andreussi L, Gras J, Capalbo L, Visotto M, Dipierri JE, Alcoba E, Fernández Gabrielli L, Ávila S, Aucar ME, Martin DM, Ormaechea GJ, Inga ME, Francone AA, Charles M, Zompa T, Pérez PJ, Lotersztein V, Nuova PJ, Canonero IB, Mahroo OA, Michaelides M, Arno G, Daich Varela M. Nationwide genetic analysis of more than 600 families with inherited eye diseases in Argentina. NPJ Genom Med 2023; 8:8. [PMID: 37217489 DOI: 10.1038/s41525-023-00352-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 04/05/2023] [Indexed: 05/24/2023] Open
Abstract
This study corresponds to the first large-scale genetic analysis of inherited eye diseases (IED) in Argentina and describes the comprehensive genetic profile of a large cohort of patients. Medical records of 22 ophthalmology and genetics services throughout 13 Argentinian provinces were analyzed retrospectively. Patients with a clinical diagnosis of an ophthalmic genetic disease and a history of genetic testing were included. Medical, ophthalmological and family history was collected. A total of 773 patients from 637 families were included, with 98% having inherited retinal disease. The most common phenotype was retinitis pigmentosa (RP, 62%). Causative variants were detected in 379 (59%) patients. USH2A, RPGR, and ABCA4 were the most common disease-associated genes. USH2A was the most frequent gene associated with RP, RDH12 early-onset severe retinal dystrophy, ABCA4 Stargardt disease, PROM1 cone-rod dystrophy, and BEST1 macular dystrophy. The most frequent variants were RPGR c.1345 C > T, p.(Arg449*) and USH2A c.15089 C > A, p.(Ser5030*). The study revealed 156/448 (35%) previously unreported pathogenic/likely pathogenic variants and 8 possible founder mutations. We present the genetic landscape of IED in Argentina and the largest cohort in South America. This data will serve as a reference for future genetic studies, aid diagnosis, inform counseling, and assist in addressing the largely unmet need for clinical trials to be conducted in the region.
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Affiliation(s)
| | - José D Luna
- Centro Privado de Ojos Romagosa SA, Córdoba, Argentina
| | - Natalia Labat
- Centro Privado de Ojos Romagosa SA, Córdoba, Argentina
| | | | | | - Evangelina Esposito
- University Clinic Reina Fabiola, Córdoba, Córdoba, Argentina
- Catholic University of Cordoba, Cordoba, Argentina
| | - Agustina Ibañez
- University Clinic Reina Fabiola, Córdoba, Córdoba, Argentina
- Catholic University of Cordoba, Cordoba, Argentina
| | | | | | | | | | | | | | | | - Mauro Visotto
- Instituto Oftalmológico Trelew, Trelew, Chubut, Argentina
| | | | - Emilio Alcoba
- Hospital Materno Infantil Dr Héctor Quintana, Jujuy, Argentina
| | | | - Silvia Ávila
- Facultad de Ciencias Médicas, Universidad Nacional del Comahue, Río Negro, Argentina
| | | | | | | | - M Eugenia Inga
- Organización Medica de Investigación, Buenos Aires, Argentina
| | | | | | - Tamara Zompa
- Charles Centro Oftalmológico, Buenos Aires, Argentina
| | | | | | - Pedro J Nuova
- Ocularyb Oftalmoclinica, Yerba Buena, Tucumán, Argentina
| | | | - Omar A Mahroo
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Michel Michaelides
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Gavin Arno
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Malena Daich Varela
- Moorfields Eye Hospital, London, UK.
- UCL Institute of Ophthalmology, University College London, London, UK.
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15
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Lee HW, Lee EK. Asymmetric presentation with a novel RP2 gene mutation in X-Linked retinitis pigmentosa: a case report. BMC Ophthalmol 2023; 23:221. [PMID: 37198560 DOI: 10.1186/s12886-023-02968-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 05/09/2023] [Indexed: 05/19/2023] Open
Abstract
BACKGROUND We present the detailed multimodal imaging analysis in a case of X-linked retinitis pigmentosa (XLRP) exhibiting a markedly asymmetric presentation with a novel RP2 mutation. CASE PRESENTATION A 25-year-old woman complained of decreased vision in the right eye as well as night blindness. Her visual acuity was 20/100 (OD) and 20/20 (OS). Fundus examination revealed bone spicule pigmentation with tessellated changes in the fundus within the posterior pole. Optical coherence tomography (OCT) showed generalized disruption of foveal microstructures in the OD. No abnormal findings were identified, but localized ellipsoid zone band losses were observed on OCT in the OS. Fundus autofluorescence revealed multiple patchy hypo-autofluorescent lesions in the OD and a tapetal-like radial reflex against a dark background in the OS. Fluorescein angiography and OCT angiography revealed diffuse mottled hyperfluorescence with reduced retinal vessel density in the OD and no evidence of vascular compromise in the OS. Goldmann perimetry demonstrated a constricted visual field, and electrophysiological assessment revealed an extinguished rod response and a severely impaired cone response in the OD. Molecular genetic tests via next-generation sequencing revealed the pathogenic variant to be a heterozygous frameshift mutation in RP2 (RP2, p.Glu269Glyfs*7), resulting in premature termination of the protein. CONCLUSIONS Random X-inactivation may be attributed to interocular differences in the severity of XLRP in female carriers. A novel frameshift mutation in the RP2 gene and a comprehensive phenotypic evaluation in the current study may broaden the spectrum of the disease in XLRP carriers.
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Affiliation(s)
- Hyun Woo Lee
- Pre-medical Program, Seoul National University College of Medicine, Seoul, Korea
| | - Eun Kyoung Lee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Hospital, #101, Daehak-ro, Jongno-gu, Seoul, Republic of Korea.
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16
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Thorson MT, Wei SE, Johnson C, Gabriel CJ, Arshavsky VY, Pearring JN. Nrl:CreERT2 mouse model to induce mosaic gene expression in rod photoreceptors. Front Mol Neurosci 2023; 16:1161127. [PMID: 37181654 PMCID: PMC10166802 DOI: 10.3389/fnmol.2023.1161127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/20/2023] [Indexed: 05/16/2023] Open
Abstract
Photoreceptors are sensory neurons that capture light within their outer segment, a narrow cylindrical organelle stacked with disc-shaped membranes housing the visual pigment. Photoreceptors are the most abundant neurons in the retina and are tightly packed to maximize the capture of incoming light. As a result, it is challenging to visualize an individual cell within a crowded photoreceptor population. To address this limitation, we developed a rod-specific mouse model that expresses tamoxifen-inducible cre recombinase under the control of the Nrl promoter. We characterized this mouse using a farnyslated GFP (GFPf) reporter mouse and found mosaic rod expression throughout the retina. The number of GFPf-expressing rods stabilized within 3 days post tamoxifen injection. At that time, the GFPf reporter began to accumulate in basal disc membranes. Using this new reporter mouse, we attempted to quantify the time course of photoreceptor disc renewal in WT and Rd9 mice, a model of X-linked retinitis pigmentosa previously proposed to have a reduced disc renewal rate. We measured GFPf accumulation in individual outer segments at 3 and 6 days post-induction and found that basal accumulation of the GFPf reporter was unchanged between WT and Rd9 mice. However, rates of renewal based on the GFPf measurements were inconsistent with historical calculations from radiolabeled pulse-chase experiments. By extending GFPf reporter accumulation to 10 and 13 days we found that this reporter had an unexpected distribution pattern that preferentially labeled the basal region of the outer segment. For these reasons the GFPf reporter cannot be used for measuring rates of disc renewal. Therefore, we used an alternative method that labels newly forming discs with a fluorescent dye to measure disc renewal rates directly in the Rd9 model and found it was not significantly different from WT. Our study finds that the Rd9 mouse has normal rates of disc renewal and introduces a novel Nrl:CreERT2 mouse for gene manipulation of individual rods.
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Affiliation(s)
- Molly T. Thorson
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, United States
| | - Stephanie E. Wei
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, United States
| | - Craig Johnson
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | | | - Vadim Y. Arshavsky
- Department of Ophthalmology, Duke University, Durham, NC, United States
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, United States
| | - Jillian N. Pearring
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, United States
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
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17
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Georgiou M, Robson AG, Jovanovic K, Guimarães TACD, Ali N, Pontikos N, Uwaydat SH, Mahroo OA, Cheetham ME, Webster AR, Hardcastle AJ, Michaelides M. RP2-Associated X-linked Retinopathy: Clinical Findings, Molecular Genetics, and Natural History. Ophthalmology 2023; 130:413-422. [PMID: 36423731 PMCID: PMC10567581 DOI: 10.1016/j.ophtha.2022.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/10/2022] [Accepted: 11/10/2022] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To review and describe in detail the clinical course, functional and anatomic characteristics of RP2-associated retinal degeneration. DESIGN Retrospective case series. PARTICIPANTS Male participants with disease-causing variants in the RP2 gene. METHODS Review of all case notes and results of molecular genetic testing, retinal imaging (fundus autofluorescence [FAF] imaging, OCT), and electrophysiology assessment. MAIN OUTCOME MEASURES Molecular genetic testing, clinical findings including best-corrected visual acuity (BCVA), qualitative and quantitative retinal imaging analysis, and electrophysiology parameters. RESULTS Fifty-four molecularly confirmed patients were identified from 38 pedigrees. Twenty-eight disease-causing variants were identified, with 20 not previously clinically characterized. Fifty-three patients (98.1%) presented with retinitis pigmentosa. The mean age of onset (range ± standard deviation [SD]) was 9.6 years (1-57 ± 9.2 years). Forty-four patients (91.7%) had childhood-onset disease, with mean age of onset of 7.6 years. The most common first symptom was night blindness (68.8%). Mean BCVA (range ± SD) was 0.91 logarithm of the minimum angle of resolution (logMAR) (0-2.7 ± 0.80) and 0.94 logMAR (0-2.7 ± 0.78) for right and left eyes, respectively. On the basis of the World Health Organization visual impairment criteria, 18 patients (34%) had low vision. The majority (17/22) showed electroretinogram (ERG) evidence of a rod-cone dystrophy. Pattern ERG P50 was undetectable in all but 2 patients. A range of FAF findings was observed, from normal to advanced atrophy. There were no statistically significant differences between right and left eyes for ellipsoid zone width (EZW) and outer nuclear layer (ONL) thickness. The mean annual rate of EZW loss was 219 μm/year, and the mean annual decrease in ONL thickness was 4.93 μm/year. No patient with childhood-onset disease had an identifiable ellipsoid zone (EZ) after the age of 26 years at baseline or follow-up. Four patients had adulthood-onset disease and a less severe phenotype. CONCLUSIONS This study details the clinical phenotype of RP2 retinopathy in a large cohort. The majority presented with early-onset severe retinal degeneration, with early macular involvement and complete loss of the foveal photoreceptor layer by the third decade of life. Full-field ERGs revealed rod-cone dystrophy in the vast majority, but with generalized (peripheral) cone system involvement of widely varying severity in the first 2 decades of life. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.
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Affiliation(s)
- Michalis Georgiou
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom; Jones Eye Institute, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Anthony G Robson
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Katarina Jovanovic
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Thales A C de Guimarães
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Naser Ali
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nikolas Pontikos
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Sami H Uwaydat
- Jones Eye Institute, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Omar A Mahroo
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michael E Cheetham
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Andrew R Webster
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Alison J Hardcastle
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michel Michaelides
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom.
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18
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Lv X, Zheng Z, Zhi X, Zhou Y, Lv J, Zhou Y, Wu B, Liu S, Shi W, Song Z, Xu J, Qu J, Xu D, Gu F. Identification of RPGR ORF15 mutation for X-linked retinitis pigmentosa in a large Chinese family and in vitro correction with prime editor. Gene Ther 2023; 30:160-166. [PMID: 35794468 DOI: 10.1038/s41434-022-00352-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 05/28/2022] [Accepted: 06/09/2022] [Indexed: 11/09/2022]
Abstract
X-linked retinitis pigmentosa (XLRP) is the most severe form of Retinitis Pigmentosa (RP) and one of the leading causes of blindness in the world. Currently, there is no effective treatment for RP. In the present study, we recruited a XLRP family and identified a 4 bp deletion mutation (c. 2234_2237del) in RPGR ORF15 with Sanger sequencing, which was located in the exact same region as the missing XES (X chromosome exome sequencing) coverage. Then, we generated cell lines harboring the identified mutation and corrected it via enhanced prime editing system (ePE). Collectively, Sanger sequencing identified a pathogenic mutation in RPGR ORF15 for XLRP which was corrected with ePE. This study provides a valuable insight for genetic counseling of the afflicted family members and prenatal diagnosis, also paves a way for applying prime editing based gene therapy in those patients.
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Affiliation(s)
- Xiujuan Lv
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Zheng Zheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Xiao Zhi
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Yilin Zhou
- College of Engineering, Boston University, Boston, MA, USA
| | - Jineng Lv
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Yue Zhou
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Binrong Wu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Sixiu Liu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Wei Shi
- Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing, 100054, China
| | - Zongming Song
- Henan Eye Hospital, Henan Eye Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University and People's Hospital of Henan University, Zhengzhou, Henan, China
| | - Jinling Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Jia Qu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China
| | - Dan Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China.
| | - Feng Gu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou, Zhejiang, 325027, China.
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19
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Travis AM, Manocha S, Willer JR, Wessler TS, Skiba NP, Pearring JN. Disrupting the ciliary gradient of active Arl3 affects rod photoreceptor nuclear migration. eLife 2023; 12:80533. [PMID: 36598133 PMCID: PMC9831603 DOI: 10.7554/elife.80533] [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: 05/24/2022] [Accepted: 01/03/2023] [Indexed: 01/05/2023] Open
Abstract
The small GTPase Arl3 is important for the enrichment of lipidated proteins to primary cilia, including the outer segment of photoreceptors. Human mutations in the small GTPase Arl3 cause both autosomal recessive and dominant inherited retinal dystrophies. We discovered that dominant mutations result in increased active G-protein-Arl3-D67V has constitutive activity and Arl3-Y90C is fast cycling-and their expression in mouse rods resulted in a displaced nuclear phenotype due to an aberrant Arl3-GTP gradient. Using multiple strategies, we go on to show that removing or restoring the Arl3-GTP gradient within the cilium is sufficient to rescue the nuclear migration defect. Together, our results reveal that an Arl3 ciliary gradient is involved in proper positioning of photoreceptor nuclei during retinal development.
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Affiliation(s)
- Amanda M Travis
- Department of Ophthalmology and Visual Science, University of Michigan-Ann ArborAnn ArborUnited States
| | - Samiya Manocha
- Department of Ophthalmology and Visual Science, University of Michigan-Ann ArborAnn ArborUnited States
| | - Jason R Willer
- Department of Ophthalmology and Visual Science, University of Michigan-Ann ArborAnn ArborUnited States
| | - Timothy S Wessler
- Department of Mathematics, University of North Carolina at Chapel HillChapel HillUnited States
| | - Nikolai P Skiba
- Department of Ophthalmology, Duke UniversityDurhamUnited States
| | - Jillian N Pearring
- Department of Ophthalmology and Visual Science, University of Michigan-Ann ArborAnn ArborUnited States,Department of Cell and Developmental Biology, University of Michigan–Ann ArborAnn ArborUnited States
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20
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Appelbaum T, Aguirre GD, Beltran WA. Identification of circular RNAs hosted by the RPGR ORF15 genomic locus. RNA Biol 2023; 20:31-47. [PMID: 36593651 PMCID: PMC9817113 DOI: 10.1080/15476286.2022.2159165] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/23/2022] [Accepted: 12/07/2022] [Indexed: 01/04/2023] Open
Abstract
Mutations in the retina-specific isoform of the gene encoding retinitis pigmentosa GTPase regulator (RPGRorf15) cause X-linked retinitis pigmentosa, a severe and early onset inherited retinal degeneration. The underlying pathogenic mechanisms and variability in disease severity remain to be fully elucidated. The present study examines structural features of the ORF15 exonic region to provide new insights into the disease pathogenesis. Using canine and human RNA samples, we identified several novel RPGR ORF15-like linear RNA transcripts containing cryptic introns (exitrons) within the annotated exon ORF15. Furthermore, using outward-facing primers designed inside exitrons in the ORF15 exonic region, we found many of previously unidentified circular RNAs (circRNAs) that formed via back fusion of linear parts of the RPGRorf15 pre-mRNAs. These circRNAs (resistant to RNAse R treatment) were found in all studied cells and tissues. Notably, some circRNAs were present in cytoplasmic and polysomal RNA fractions. Although certain RPGR circRNAs may be cell type specific, we found some of the same circRNAs expressed in different cell types, suggesting similarities in their biogenesis and functions. Sequence analysis of RPGR circRNAs revealed several remarkable features, including identification of N6-methyladenosine (m6A) consensus sequence motifs and high prevalence of predictive microRNA binding sites pointing to the functional roles of these circRNAs. Our findings also illustrate the presence of non-canonical RPGR circRNA biogenesis pathways independent of the known back splicing mechanism. The obtained data on novel RPGR circRNAs further underline structural complexity of the RPGR ORF15 region and provide a potential molecular basis for the disease phenotypic heterogeneity.
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Affiliation(s)
- Tatyana Appelbaum
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Gustavo D. Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - William A. Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
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21
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Lynn J, Raney A, Britton N, Ramoin J, Yang RW, Radojevic B, McClard CK, Kingsley R, Coussa RG, Bennett LD. Genetic Diagnosis for 64 Patients with Inherited Retinal Disease. Genes (Basel) 2022; 14:74. [PMID: 36672815 PMCID: PMC9859429 DOI: 10.3390/genes14010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/07/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
The overlapping genetic and clinical spectrum in inherited retinal degeneration (IRD) creates challenges for accurate diagnoses. The goal of this work was to determine the genetic diagnosis and clinical features for patients diagnosed with an IRD. After signing informed consent, peripheral blood or saliva was collected from 64 patients diagnosed with an IRD. Genetic testing was performed on each patient in a Clinical Laboratory Improvement Amendments of 1988 (CLIA) certified laboratory. Mutations were verified with Sanger sequencing and segregation analysis when possible. Visual acuity was measured with a traditional Snellen chart and converted to a logarithm of minimal angle of resolution (logMAR). Fundus images of dilated eyes were acquired with the Optos® camera (Dunfermline, UK). Horizontal line scans were obtained with spectral-domain optical coherence tomography (SDOCT; Spectralis, Heidelberg, Germany). Genetic testing combined with segregation analysis resolved molecular and clinical diagnoses for 75% of patients. Ten novel mutations were found and unique genotype phenotype associations were made for the genes RP2 and CEP83. Collective knowledge is thereby expanded of the genetic basis and phenotypic correlation in IRD.
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Affiliation(s)
- Jacob Lynn
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Austin Raney
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Nathaniel Britton
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Josh Ramoin
- College of Osteopathic Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Ryan W. Yang
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Bojana Radojevic
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Cynthia K. McClard
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Ronald Kingsley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Razek Georges Coussa
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Lea D. Bennett
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
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22
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Cheloni R, Jackson D, Moosajee M. A Natural History Study of RP2-Related Retinopathy. J Clin Med 2022; 11:jcm11236877. [PMID: 36498452 PMCID: PMC9738434 DOI: 10.3390/jcm11236877] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/10/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
X-linked retinitis pigmentosa (RP) is a severe form of RP, often with early macular involvement. This study aimed to characterise the natural history of patients with a diagnosis of X-linked RP due to RP2 mutations. Clinical details, best-corrected visual acuity (BCVA) and multimodal retinal imaging were retrospectively collected from patients with RP2 variants from Moorfields Eye Hospital (London, UK). Measures of the ellipsoid-zone (EZ) width, central retinal thickness (CRT), and thickness of the photoreceptor and retinal pigment epithelium complex (PR+RPE, taken between the external limiting membrane and RPE) were extracted from spectral-domain optical coherence tomography (SD-OCT) scans. A total of 47 affected males (median baseline age: 20 years, IQR: 12.5−36.5) were included, and 41 had two or more visits (median follow-up: 8.0 years, IQR: 3.2−14.5). A total of 24 RP2 variants were identified, 13 of which were novel. BCVA dropped from 0.66 LogMAR at baseline (IQR, 0.35−1.4) to 1.3 LogMAR at the most recent visit (IQR: 0.6−1.4). SD-OCT revealed a prevalent outer retinal atrophy (n = 23/35, 65.7%), and measurable EZ width at baseline in 34.3% of patients (n = 12). Age significantly affected all quantitative measures (p < 0.001) except EZ width (p = 0.58), with exponential decays of 46−49% and 12.6−33.9% per decade for BCVA and SD-OCT measures, respectively. RP2 patients exhibited rapid progression to outer retina atrophy and early macular involvement with substantial vision loss by age 30−40.
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Affiliation(s)
- Riccardo Cheloni
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - Daniel Jackson
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
- The Francis Crick Institute, London NW1 1AT, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
- Correspondence:
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23
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Liu X, Jia R, Meng X, Wang L, Yang L. Analysis of RPGR gene mutations in 41 Chinese families affected by X-linked inherited retinal dystrophy. Front Genet 2022; 13:999695. [PMID: 36276946 PMCID: PMC9582779 DOI: 10.3389/fgene.2022.999695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Background: This study analyzed the phenotypes and genotypes of 41 Chinese families with inherited retinal dystrophy (IRD) and RPGR gene mutations.Methods: This retrospective analysis evaluated a cohort of 41 patients who were subjected to a specific Hereditary Eye Disease Enrichment Panel (HEDEP) analysis. All (likely) pathogenic variants were determined by Sanger sequencing, and co-segregation analyses were performed on the available family members. All cases were subjected to Sanger sequencing for RPGR open reading frame 15 (ORF15) mutations.Results: A total of 41 probands from different families with a clinical diagnosis of retinitis pigmentosa (RP; 34 cases) and cone-rod dystrophy (CORD; 7 cases) were included in this cohort. According to clinical information, 2, 18, and 21 cases were first assigned as autosomal dominant (AD), sporadic, and X-linked (XL) inheritance, respectively. Several cases of affected females who presented with a male phenotype have been described, posing challenges at diagnosis related to the apparent family history of AD. Mutations were located in RPGR exons or introns 1–14 and in ORF15 of 12 of 41 (29.3%) and 29 of 41 (70.7%) subjects, respectively. Thirty-four (likely) pathogenic mutations were identified. Frameshifts were the most frequently observed variants, followed by nonsense, splice, and missense mutations. Herein, a detailed description of four RP patients carrying RPGR intronic mutations is reported, and in vitro splice assays were performed to confirm the pathogenicity of these intronic mutations.Conclusion: Our findings provide useful insights for the genetic and clinical counseling of patients with XL IRD, which will be useful for ongoing and future gene therapy trials.
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Affiliation(s)
- Xiaozhen Liu
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Ruixuan Jia
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Xiang Meng
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Likun Wang
- Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Beijing Key Laboratory of Tumor Systems Biology, Peking-Tsinghua Center of Life Sciences, Peking University Health Science Center, Beijing, China
- *Correspondence: Likun Wang, ; Liping Yang,
| | - Liping Yang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
- *Correspondence: Likun Wang, ; Liping Yang,
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24
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Vinikoor-Imler LC, Simpson C, Narayanan D, Abbasi S, Lally C. Prevalence of RPGR-mutated X-linked retinitis pigmentosa among males. Ophthalmic Genet 2022; 43:581-588. [PMID: 36004681 DOI: 10.1080/13816810.2022.2109686] [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: 10/15/2022]
Abstract
BACKGROUND X-linked retinitis pigmentosa (XLRP) is a rare inherited retinal disease predominantly affecting males. MATERIALS AND METHODS A comprehensive literature review was conducted to determine the prevalence of retinitis pigmentosa GTPase regulator (RPGR)-mutated XLRP. Identified studies were used to estimate four components among males: the prevalence of retinitis pigmentosa (RP), the proportion of RP that was X-linked, the proportion of misclassified inheritance type among RP cases, and the proportion of XLRP that was RPGR-mutated. Studies providing a direct estimate of XLRP prevalence were also included. The components' sample size-weighted averages were combined to determine an overall prevalence estimate. RESULTS The prevalence of XLRP was estimated to be between 2.7-3.5 per 100,000 males in the US, Europe, and Australia. After correction for misclassification, the prevalence increased to 4.0-5.2 per 100,000 males. Finally, the proportion of XLRP cases due to RPGR mutations was applied, resulting in an RPGR-mutated XLRP estimate of 3.4-4.4 per 100,000 males. Studies from other countries were consistent with the results for the overall XLRP prevalence but were not included in the final calculation because of regional variations and lack of detailed information. CONCLUSIONS These findings address an important gap in the understanding of RPGR-mutated XLRP by summarizing the global burden of this condition.
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Affiliation(s)
| | | | - Divya Narayanan
- Global Medical Affairs, Biogen, Cambridge, Massachusetts, USA
| | - Saad Abbasi
- Global Medical Affairs, Biogen, Cambridge, Massachusetts, USA
| | - Cathy Lally
- Epidemiologic Research & Methods, LLC, Atlanta, Georgia, USA
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25
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Hall JC, Paull D, Pébay A, Lidgerwood GE. Human pluripotent stem cells for the modelling of retinal pigment epithelium homeostasis and disease: A review. Clin Exp Ophthalmol 2022; 50:667-677. [PMID: 35739648 PMCID: PMC9546239 DOI: 10.1111/ceo.14128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/06/2022] [Accepted: 06/19/2022] [Indexed: 12/05/2022]
Abstract
Human pluripotent stem cells (hPSCs), which include induced pluripotent stem cells and embryonic stem cells, are powerful tools for studying human development, physiology and disease, including those affecting the retina. Cells from selected individuals, or specific genetic backgrounds, can be differentiated into distinct cell types allowing the modelling of diseases in a dish for therapeutic development. hPSC‐derived retinal cultures have already been used to successfully model retinal pigment epithelium (RPE) degeneration for various retinal diseases including monogenic conditions and complex disease such as age‐related macular degeneration. Here, we will review the current knowledge gained in understanding the molecular events involved in retinal disease using hPSC‐derived retinal models, in particular RPE models. We will provide examples of various conditions to illustrate the scope of applications associated with the use of hPSC‐derived RPE models.
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Affiliation(s)
- Jenna C Hall
- Department of Anatomy and Physiology The University of Melbourne Parkville Victoria Australia
| | - Daniel Paull
- The New York Stem Cell Foundation Research Institute New York New York USA
| | - Alice Pébay
- Department of Anatomy and Physiology The University of Melbourne Parkville Victoria Australia
- Department of Surgery, Royal Melbourne Hospital The University of Melbourne Parkville Victoria Australia
| | - Grace E. Lidgerwood
- Department of Anatomy and Physiology The University of Melbourne Parkville Victoria Australia
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26
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Liu HL, Gao FG, Wang DD, Hu FY, Xu P, Chang Q, Xu GZ, Wu JH. Mutation Analysis of the RPGR Gene in a Chinese Cohort. Front Genet 2022; 13:850122. [PMID: 35432464 PMCID: PMC9008860 DOI: 10.3389/fgene.2022.850122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 02/17/2022] [Indexed: 12/05/2022] Open
Abstract
Purpose: The purpose of this study was to investigate the clinical and genetic characteristics of the retinitis pigmentosa GTPase regulatory factor gene (RPGR) in a Chinese cohort. Methods: A retrospective analysis was performed on 80 subjects with RPGR-retinal dystrophy (RPGR-RD) for detailed genetic and clinical characterization. The panel-based next-generation sequencing of 792 causative genes involved in common genetic eye diseases was conducted in all individuals, followed by clinical variant interpretation. Information, including age, sex, geographic distribution, family history, consanguineous marriage, age at symptom onset, disease duration, best corrected visual acuity (BCVA), and complete ophthalmologic examination results, was collected. Results: This cohort (41 men and 39 women) included 26 families (26 probands and their available family members) and 13 sporadic cases. The average age of these participants was 36.35 ± 17.68 years, and the majority of the families were from eastern China (28 families, 71.79%). The average duration of disease in the probands was 22.68 ± 15.80 years. In addition, the average BCVA values of the right and left eyes in the probands were 0.96 ± 0.77 and 1.00 ± 0.77, respectively. A total of 34 RPGR variants were identified, including 6 reported variants and 28 novel variants. Among these variants, NM_001034853.1: c.2899_2902delGAAG and c.2744_2745ins24 were considered de novo variants. The majority of the RPGR variants were classified as likely pathogenic, accounting for 70.59% of the variants (24 variants). The most common nucleotide and amino acid changes identified in this study were deletions (16 variants, 45.06%) and frameshifts (17 variants, 50.00%), respectively. Genetic analysis revealed that these RPGR variants were distributed in 10 different subregions of RPGR, and 70.59% of the RPGR variants (24 variants) were located in exon 15. Four RPGR variants, NM_001034853.1: c.2405_2406delAG, c.1345C > T, c.2218G > T and c.2236_2237delGA, occurred at a very high frequency of 28.21% (11 families) among 39 unrelated families. Conclusion: This study expands the known mutational spectrum of RPGR, and we provide a new reference for the genetic diagnosis of RPGR variants.
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Affiliation(s)
- Hong-Li Liu
- Eye Institute, Eye and ENT Hospital, College of Medicine, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
| | - Feng-Guan Gao
- Eye Institute, Eye and ENT Hospital, College of Medicine, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
| | - Dan-Dan Wang
- Eye Institute, Eye and ENT Hospital, College of Medicine, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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-Yuan Hu
- Eye Institute, Eye and ENT Hospital, College of Medicine, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
| | - Ji-Hong Wu
- Eye Institute, Eye and ENT Hospital, College of Medicine, Fudan University, Shanghai, China
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science and Collaborative Innovation Center for Brain Science, Shanghai Medical College, 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
- *Correspondence: Ji-Hong Wu,
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27
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Yang J, Zhou L, Ouyang J, Xiao X, Sun W, Li S, Zhang Q. Genotype-Phenotype Analysis of RPGR Variations: Reporting of 62 Chinese Families and a Literature Review. Front Genet 2021; 12:600210. [PMID: 34745198 PMCID: PMC8565807 DOI: 10.3389/fgene.2021.600210] [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: 08/29/2020] [Accepted: 04/27/2021] [Indexed: 02/05/2023] Open
Abstract
Purpose RPGR is the most common cause of X-linked retinitis pigmentosa (RP), of which female carriers are also frequently affected. The aim of the current study was to explore the RPGR variation spectrum and associated phenotype based on the data from our lab and previous studies. Methods Variants in RPGR were selected from exome sequencing data of 7,092 probands with different eye conditions. The probands and their available family members underwent comprehensive ocular examinations. Similar data were collected from previous reports through searches in PubMed, Web of Science, and Google Scholar. Systematic analyses of genotypes, phenotypes and their correlations were performed. Results A total of 46 likely pathogenic variants, including nine missense and one in-frame variants in RCC1-like domain and 36 truncation variants, in RPGR were detected in 62 unrelated families in our in-house cohort. In addition, a total of 585 variants, including 491 (83.9%) truncation variants, were identified from the literature. Systematic analysis of variants from our in-house dataset, literature, and gnomAD suggested that most of the pathogenic variants of RPGR were truncation variants while pathogenic missense and in-frame variants were enriched in the RCC1-like domain. Phenotypic variations were present between males and female carriers, including more severe refractive error but better best corrected visual acuity (BCVA) in female carriers than those in males. The male patients showed a significant reduction of BCVA with increase of age and males with exon1-14 variants presented a better BCVA than those with ORF15 variants. For female carriers, the BCVA also showed significant reduction with increase of age, but BCVA in females with exon1-14 variants was not significant difference compared with those with ORF15 variants. Conclusion Most pathogenic variants of RPGR are truncations. Missense and in-frame variants located outside of the RCC1-like domain might be benign and the pathogenicity criteria for these variants should be considered with greater caution. The BCVA and refractive error are different between males and female carriers. Increase of age and location of variants in ORF15 contribute to the reduction of BCVA in males. These results are valuable for understanding genotypes and phenotypes of RPGR.
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Affiliation(s)
- Junxing Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lin Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Jiamin Ouyang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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Liu W, Guo R, Hao H, Ji J. Identification of a novel RHO heterozygous nonsense mutation in a Chinese family with autosomal dominant retinitis pigmentosa. BMC Ophthalmol 2021; 21:360. [PMID: 34635090 PMCID: PMC8504003 DOI: 10.1186/s12886-021-02125-9] [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: 06/16/2021] [Accepted: 09/28/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To explore the molecular genetic cause of a four-generation autosomal dominant retinitis pigmentosa family in China. METHODS Targeted region sequencing was performed to detect the potential mutation, and Sanger sequencing was used to validate the mutation. Multiple sequence alignment from different species was performed by CLUSTALW. The structures of wild-type and the mutant RHO were modeled by Swiss-Model Server and shown using a PyMOL Molecular Graphic system. RESULTS A novel heterozygous nonsense mutation (c.1015 A > T, p.Lys339Ter, p.K339X) within RHO, which cosegregated with retinitis pigmentosa phenotype was detected in this family. Bioinformatics analysis showed the mutation was located in a highly conserved region, and the mutation was predicted to be pathogenic. CONCLUSIONS We identified a novel heterozygous nonsense mutation of RHO gene in a Chinese family with retinitis pigmentosa by target region sequencing and our bioinformatics analysis indicated that the mutation is pathogenic. Our results can broaden the spectrum of RHO gene mutation and enrich the phenotype-genotype correlation of retinitis pigmentosa.
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Affiliation(s)
- Wei Liu
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China.
| | - Ruru Guo
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Huijie Hao
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
| | - Jian Ji
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, 300384, China
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Iannaccone A, Alekseev O. Choosing Outcome Measures and Assessing Efficacy of Therapeutic Interventions in Inherited Retinal Diseases: The Importance of Natural History Studies. Int Ophthalmol Clin 2021; 61:47-61. [PMID: 34584044 DOI: 10.1097/iio.0000000000000380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Nuzbrokh Y, Ragi SD, Tsang SH. Gene therapy for inherited retinal diseases. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1278. [PMID: 34532415 PMCID: PMC8421966 DOI: 10.21037/atm-20-4726] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 11/04/2020] [Indexed: 01/04/2023]
Abstract
Inherited retinal diseases (IRDs) are a genetically variable collection of devastating disorders that lead to significant visual impairment. Advances in genetic characterization over the past two decades have allowed identification of over 260 causative mutations associated with inherited retinal disorders. Thought to be incurable, gene supplementation therapy offers great promise in treating various forms of these blinding conditions. In gene replacement therapy, a disease-causing gene is replaced with a functional copy of the gene. These therapies are designed to slow disease progression and hopefully restore visual function. Gene therapies are typically delivered to target retinal cells by subretinal (SR) or intravitreal (IVT) injection. The historic Food and Drug Administration (FDA) approval of voretigene neparvovec for RPE65-associated Leber's congenital amaurosis (LCA) spurred tremendous optimism surrounding retinal gene therapy for various other monogenic IRDs. Novel disease-causing mutations continue to be discovered annually, and targeted genetic therapy is now under development in clinical and preclinical models for many IRDs. Numerous clinical trials for other IRDs are ongoing or have recently completed. Disorders being targeted for genetic therapy include retinitis pigmentosa (RP), choroideremia (CHM), achromatopsia (ACHM), Leber's hereditary optic neuropathy, usher syndrome (USH), X-linked retinoschisis, and Stargardt disease. Here, we provide an update of completed, ongoing, and planned clinical trials using gene supplementation strategies for retinal degenerative disorders.
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Affiliation(s)
- Yan Nuzbrokh
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York, NY, USA.,Jonas Children's Vision Care, New York, NY, USA.,Renaissance School of Medicine at Stony Brook University, Stony Brook, New York, NY, USA
| | - Sara D Ragi
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York, NY, USA.,Jonas Children's Vision Care, New York, NY, USA
| | - Stephen H Tsang
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York, NY, USA.,Jonas Children's Vision Care, New York, NY, USA.,Department of Pathology & Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
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Beigi F, Del Pozo-Valero M, Martin-Merida I, Manaviat MR, Ayuso C, Ghasemi N. Homozygous females for a X-linked RPGR-ORF15 mutation in an Iranian family with retinitis pigmentosa. Exp Eye Res 2021; 211:108714. [PMID: 34390733 DOI: 10.1016/j.exer.2021.108714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/10/2021] [Accepted: 07/30/2021] [Indexed: 11/17/2022]
Abstract
Mutations in Retinitis pigmentosa GTPase regulator gene (RPGR) are the most common cause of X-linked retinitis pigmentosa (RP). Almost 60% of disease-causing RPGR mutations are located in ORF-15 region which cannot be detected by Next Generation Sequencing (NGS) due to the existence of highly repetitive regions. An Iranian family with a priori diagnosis of autosomal dominant RP was studied by Sanger sequencing of ORF15 of RPGR gene after an inconclusive NGS result. A frameshift two-base-pair deletion (c.2323_2324del, p.Arg775Glufs*59) in this region was segregating in both affected hemizygous males and affected homozygous females. To our knowledge, this is the first example of homozygous females for RPGR-ORF15 mutations.
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Affiliation(s)
- Fahimeh Beigi
- Department of Medical Genetics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Marta Del Pozo-Valero
- Department of Clinical Genetics and Genomics, University Hospital Fundacion Jimenez Diaz, Health Research Institute Fundacion Jimenez Diaz (IIS-FJD, UAM), Madrid, Spain; CIBERER (Biomedical Research Network Centre for Rare Diseases), ISCIII, Madrid, Spain
| | - Inmaculada Martin-Merida
- Department of Clinical Genetics and Genomics, University Hospital Fundacion Jimenez Diaz, Health Research Institute Fundacion Jimenez Diaz (IIS-FJD, UAM), Madrid, Spain; CIBERER (Biomedical Research Network Centre for Rare Diseases), ISCIII, Madrid, Spain
| | - Masoud Reza Manaviat
- Department of Ophthalmology, Shahid Sadoughi University of Medical Science, Yazd Diabetes Research Center, Yazd, Iran
| | - Carmen Ayuso
- Department of Clinical Genetics and Genomics, University Hospital Fundacion Jimenez Diaz, Health Research Institute Fundacion Jimenez Diaz (IIS-FJD, UAM), Madrid, Spain; CIBERER (Biomedical Research Network Centre for Rare Diseases), ISCIII, Madrid, Spain.
| | - Nasrin Ghasemi
- Abortion Research Centre, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
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Duzkale N, Arslan U. Investigation of genotype-phenotype relationship in Turkish patients with inherited retinal disease by next generation sequencing. Ophthalmic Genet 2021; 42:674-684. [PMID: 34315337 DOI: 10.1080/13816810.2021.1952616] [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: 10/20/2022]
Abstract
BACKGROUND Inherited retinal dystrophies (IRDs) are a group of retinal diseases genetically and clinically highly heterogeneous and associated with more than 300 genes. This study aims to investigate the genetic basis of Turkish patients with IRDs. MATERIALS AND METHODS In the study, genes related to retinal diseases in 86 IRDs patients were analyzed using the Next Generations Sequencing method (NGS). RESULTS The mean age of 86 patients was 35 and the mean age at diagnosis was 18. There was consanguinity between the parents of 62% of these patients. Fifty-six retinal disease-associated genes of 46 patients and 230 retinal disease-associated genes of 40 patients were examined. Genetic analysis provides a molecular diagnosis in a total of 53 (61.6%) patients. The genes responsible for the IRDs phenotype were frequently identified as ABCA4 (25%), EYS (11%), and RDH12 (9%). There was no significant difference between those with and without a molecular diagnosis in terms of demographic characteristics and family history. CONCLUSIONS Determination of genetic cause by NGS method in IRDs subgroups that are difficult to define by ophthalmic examination ensures that patients receive accurate diagnosis, treatment and counseling. This study contributed to the understanding of the genotype-phenotype relationship of Turkish patients with IRDs.
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Affiliation(s)
- Neslihan Duzkale
- Department of Medical Genetic, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey
| | - Umut Arslan
- Department of Bioretina, Ankara University Technopolis, Ankara, Turkey
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Gumerson JD, Alsufyani A, Yu W, Lei J, Sun X, Dong L, Wu Z, Li T. Restoration of RPGR expression in vivo using CRISPR/Cas9 gene editing. Gene Ther 2021; 29:81-93. [PMID: 34257417 PMCID: PMC8856954 DOI: 10.1038/s41434-021-00258-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 03/29/2021] [Accepted: 04/01/2021] [Indexed: 11/29/2022]
Abstract
Mutations in the gene for Retinitis Pigmentosa GTPase Regulator (RPGR) cause the X-linked form of inherited retinal degeneration, and the majority are frameshift mutations in a highly repetitive, purine-rich region of RPGR known as the OFR15 exon. Truncation of the reading frame in this terminal exon ablates the functionally important C-terminal domain. We hypothesized that targeted excision in ORF15 by CRISPR/Cas9 and the ensuing repair by non-homologous end joining could restore RPGR reading frame in a portion of mutant photoreceptors thereby correcting gene function in vivo. We tested this hypothesis in the rd9 mouse, a naturally occurring mutant line that carries a frameshift mutation in RPGRORF15, through a combination of germline and somatic gene therapy approaches. In germline gene-edited rd9 mice, probing with RPGR domain-specific antibodies demonstrated expression of full length RPGRORF15 protein. Hallmark features of RPGR mutation-associated early disease phenotypes, such as mislocalization of cone opsins, were no longer present. Subretinal injections of the same guide RNA (sgRNA) carried in AAV sgRNA and SpCas9 expression vectors restored reading frame of RPGRORF15 in a subpopulation of cells with broad distribution throughout the retina, confirming successful correction of the mutation. These data suggest that a simplified form of genome editing mediated by CRISPR, as described here, could be further developed to repair RPGRORF15 mutations in vivo.
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Affiliation(s)
- Jessica D Gumerson
- Neurobiology Neurodegeneration & Repair Laboratory (N-NRL), National Eye Institute, Bethesda, MD, USA.
| | - Amal Alsufyani
- Neurobiology Neurodegeneration & Repair Laboratory (N-NRL), National Eye Institute, Bethesda, MD, USA.,King Saud bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia.,Montgomery College, Rockville, MD, USA
| | - Wenhan Yu
- Ocular Gene Therapy Core, National Eye Institute, Bethesda, MD, USA
| | - Jingqi Lei
- Genetic Engineering Core, National Eye Institute, Bethesda, MD, USA
| | - Xun Sun
- Neurobiology Neurodegeneration & Repair Laboratory (N-NRL), National Eye Institute, Bethesda, MD, USA
| | - Lijin Dong
- Genetic Engineering Core, National Eye Institute, Bethesda, MD, USA
| | - Zhijian Wu
- Ocular Gene Therapy Core, National Eye Institute, Bethesda, MD, USA
| | - Tiansen Li
- Neurobiology Neurodegeneration & Repair Laboratory (N-NRL), National Eye Institute, Bethesda, MD, USA.
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A novel mutation of the RPGR gene in a Chinese X-linked retinitis pigmentosa family and possible involvement of X-chromosome inactivation. Eye (Lond) 2021; 35:1688-1696. [PMID: 32839555 PMCID: PMC8169654 DOI: 10.1038/s41433-020-01150-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 07/14/2020] [Accepted: 08/13/2020] [Indexed: 01/30/2023] Open
Abstract
OBJECTIVES The objective of this study is to investigate the molecular mechanisms and genotype-phenotype correlations of a Chinese family with X-linked retinitis pigmentosa (XLRP). METHODS A four-generation family with a total of 41 individuals including 7 affected males was recruited. All subjects in this pedigree underwent a complete ophthalmic examination. Targeted capture and next-generation sequencing were performed on the proband using a multigene panel containing 57 known causative genes of retinitis pigmentosa (RP), including RP1, RP2, RPGR, RHO, PRPH2, CRB1 among others. All variants were verified in the remaining family members by polymerase chain reaction amplification and Sanger sequencing. Blood DNA was used for X-chromosome inactivation analysis in female carriers. RESULTS All the affected individuals were diagnosed with RP. The affected males showed symptoms from the first decade, while the female carriers had onset in the second decade or later. A frameshift mutation c.345_348delTGAA in the RPGR gene was identified in all affected males and female carriers. By XCI analysis, we found that there was little correlation between their phenotype and the methylation status of their X chromosomes. CONCLUSIONS A novel mutation c.345_348delTGAA of the RPGR gene was identified, expanding the spectrum of RPGR mutations causing XLRP. In this pedigree, the phenotype extended to female carriers, in whom RP was milder and its onset delayed compared to hemizygous males. Although lack of strong correlation between X-inactivation and the severity of the disease, the milder, variable effects in female carriers still could reflect X-inactivation patterns in the retina of each individual.
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Di Iorio V, Karali M, Melillo P, Testa F, Brunetti-Pierri R, Musacchia F, Condroyer C, Neidhardt J, Audo I, Zeitz C, Banfi S, Simonelli F. Spectrum of Disease Severity in Patients With X-Linked Retinitis Pigmentosa Due to RPGR Mutations. Invest Ophthalmol Vis Sci 2021; 61:36. [PMID: 33372982 PMCID: PMC7774109 DOI: 10.1167/iovs.61.14.36] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Purpose The purpose of this study was to perform a detailed longitudinal phenotyping of X-linked retinitis pigmentosa (RP) caused by mutations in the RPGR gene during a long follow-up period. Methods An Italian cohort of 48 male patients (from 31 unrelated families) with RPGR-associated RP was clinically assessed at a single center (mean follow-up = 6.5 years), including measurements of best-corrected visual acuity (BCVA), Goldmann visual field (GVF), optical coherence tomography (OCT), fundus autofluorescence (FAF), microperimetry, and full-field electroretinography (ERG). Results Patients (29.6 ± 15.2 years) showed a mean BCVA of 0.6 ± 0.7 logMAR, mostly with myopic refraction (79.2%). Thirty patients (62.5%) presented a typical RP fundus, while the remaining sine pigmento RP. Over the follow-up, BCVA significantly declined at a mean rate of 0.025 logMAR/year. Typical RP and high myopia were associated with a significantly faster decline of BCVA. Blindness was driven primarily by GVF loss. ERG responses with a rod-cone pattern of dysfunction were detectable in patients (50%) that were significantly younger and more frequently presented sine pigmento RP. Thirteen patients (27.1%) had macular abnormalities without cystoid macular edema. Patients (50%) with a perimacular hyper-FAF ring were significantly younger, had a higher BCVA and a better-preserved ellipsoid zone band than those with markedly decreased FAF. Patients harboring pathogenic variants in exons 1 to 14 showed a milder phenotype compared to those with ORF15 mutations. Conclusions Our monocentric, longitudinal retrospective study revealed a spectrum disease progression in male patients with RPGR-associated RP. Slow disease progression correlated with sine pigmento RP, absence of high myopia, and mutations in RPGR exons 1 to 14.
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Affiliation(s)
- Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Marianthi Karali
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy.,Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Paolo Melillo
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | | | | | - John Neidhardt
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University Oldenburg, Oldenburg, Germany
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC, France.,Institute of Ophthalmology, University College of London, London, United Kingdom
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Medical Genetics, Department of Precision Medicine, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
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Appelbaum T, Murgiano L, Becker D, Santana E, Aguirre GD. Candidate Genetic Modifiers for RPGR Retinal Degeneration. Invest Ophthalmol Vis Sci 2021; 61:20. [PMID: 33326016 PMCID: PMC7745631 DOI: 10.1167/iovs.61.14.20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Purpose To define genetic variants associated with variable severity of X-linked progressive retinal atrophy 1 (XLPRA1) caused by a five-nucleotide deletion in canine RPGR exon ORF15. Methods A genome-wide association study (GWAS) was performed in XLPRA1 phenotype informative pedigree. Whole genome sequencing (WGS) was used for mutational analysis of genes within the candidate genomic region. Retinas of normal and mutant dogs were used for gene expression, gene structure, and RNA duplex analyses. Results GWAS followed by haplotype phasing identified an approximately 4.6 Mb candidate genomic interval on CFA31 containing seven protein-coding genes expressed in retina (ROBO1, ROBO2, RBM11, NRIP1, HSPA13, SAMSN1, and USP25). Furthermore, we identified and characterized two novel lncRNAs, ROBO1-AS and ROBO2-AS, that display overlapping gene organization with axon guidance pathway genes ROBO1 and ROBO2, respectively, producing sense-antisense gene pairs. Notably, ROBO1-AS and ROBO2-AS act in cis to form lncRNA/mRNA duplexes with ROBO1 and ROBO2, respectively, suggesting important roles for these lncRNAs in the ROBO regulatory network. A subsequent WGS identified candidate genes within the genomic region on CFA31 that might be implicated in modifying severity of XLPRA1. This approach led to discovery of genetic variants in ROBO1, ROBO1-AS, ROBO2-AS, and USP25 that are strongly associated with the XLPRA1 moderate phenotype. Conclusions The study provides new insights into the genetic basis of phenotypic variation in severity of RPGRorf15-associated retinal degeneration. Our findings suggest an important role for ROBO pathways in disease progression further expanding on our previously reported changes of ROBO1 expression in XLPRA1 retinas.
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Affiliation(s)
- Tatyana Appelbaum
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Leonardo Murgiano
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Doreen Becker
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States.,Leibniz Institute for Farm Animal Biology (FBN), Institute of Genome Biology, Dummerstorf, Germany
| | - Evelyn Santana
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Gustavo D Aguirre
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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Moreno-Leon L, West EL, O’Hara-Wright M, Li L, Nair R, He J, Anand M, Sahu B, Chavali VRM, Smith AJ, Ali RR, Jacobson SG, Cideciyan AV, Khanna H. RPGR isoform imbalance causes ciliary defects due to exon ORF15 mutations in X-linked retinitis pigmentosa (XLRP). Hum Mol Genet 2021; 29:3706-3716. [PMID: 33355362 PMCID: PMC7823108 DOI: 10.1093/hmg/ddaa269] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/03/2020] [Accepted: 12/09/2020] [Indexed: 12/28/2022] Open
Abstract
Mutations in retinitis pigmentosa GTPase regulator (RPGR) cause severe retinal ciliopathy, X-linked retinitis pigmentosa. Although two major alternatively spliced isoforms, RPGRex1-19 and RPGRORF15, are expressed, the relative importance of these isoforms in disease pathogenesis is unclear. Here, we analyzed fibroblast samples from eight patients and found that all of them form longer cilia than normal controls, albeit to different degrees. Although all mutant RPGRORF15 messenger RNAs (mRNAs) are unstable, their steady-state levels were similar or higher than those in the control cells, suggesting there may be increased transcription. Three of the fibroblasts that had higher levels of mutant RPGRORF15 mRNA also exhibited significantly higher levels of RPGRex1-19 mRNA. Four samples with unaltered RPGRex1-19 levels carried mutations in RPGRORF15 that resulted in this isoform being relatively less stable. Thus, in all cases, the RPGRex1-19/RPGRORF15 isoform ratio was increased, and this was highly correlative to the cilia extension defect. Moreover, overexpression of RPGRex1-19 (mimicking the increase in RPGRex1-19 to RPGRORF15 isoform ratio) or RPGRORF15 (mimicking reduction of the ratio) resulted in significantly longer or shorter cilia, respectively. Notably, the cilia length defect appears to be attributable to both the loss of the wild-type RPGRORF15 protein and to the higher levels of the RPGRex1-19 isoform, indicating that the observed defect is due to the altered isoform ratios. These results suggest that maintaining the optimal RPGRex1-9 to RPGRORF15 ratio is critical for cilia growth and that designing strategies that focus on the best ways to restore the RPGRex1-19/RPGRORF15 ratio may lead to better therapeutic outcomes.
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Affiliation(s)
- Laura Moreno-Leon
- Department of Ophthalmology & Visual Sciences, UMass Medical School, Worcester, MA 01655, USA
| | - Emma L West
- Division of Molecular Therapy, UCL Institute of Ophthalmology, London EC1V 9El, UK
| | | | - Linjing Li
- Department of Ophthalmology & Visual Sciences, UMass Medical School, Worcester, MA 01655, USA
| | - Rohini Nair
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jie He
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Manisha Anand
- Department of Ophthalmology & Visual Sciences, UMass Medical School, Worcester, MA 01655, USA
| | - Bhubanananda Sahu
- Department of Ophthalmology & Visual Sciences, UMass Medical School, Worcester, MA 01655, USA
| | | | - Alexander J Smith
- Division of Molecular Therapy, UCL Institute of Ophthalmology, London EC1V 9El, UK
| | - Robin R Ali
- Division of Molecular Therapy, UCL Institute of Ophthalmology, London EC1V 9El, UK
| | - Samuel G Jacobson
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hemant Khanna
- Department of Ophthalmology & Visual Sciences, UMass Medical School, Worcester, MA 01655, USA
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Liu YS, Pan JQ, Wan JF, Ren CY, Xu ZH, Pan XB, Gao RN, Liu SQ, Zhang JL, Yao QH, Wang JH, Li EM, Rao JH, Hou P, Chen JH. A novel missense mutation of RPGR identified from retinitis pigmentosa affects splicing of the ORF15 region and causes loss of transcript heterogeneity. Biochem Biophys Res Commun 2020; 531:172-179. [PMID: 32788070 DOI: 10.1016/j.bbrc.2020.06.109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 06/22/2020] [Indexed: 02/05/2023]
Abstract
Mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene, are the major cause of X-linked retinitis pigmentosa (RP), in which exon open reading frame 15 (ORF15) of RPGR has been implicated to play a substantial role. We identified a novel hemizygous missense mutation E585K of RPGR from whole-exome sequencing of RP. RNA-Seq analysis and functional study were conducted to investigate the underlying pathogenic mechanism of the mutation. Our results showed that the mutation actually affected RPGR ORF15 splicing. RNA-Seq analysis of the human retina followed by validation in cells revealed a complex splicing pattern near the 3' boundary of RPGR exon 14 in the ORF15 region, resulting from a variety of alternative splicing events (ASEs). The wildtype RPGR mini-gene expressed in human 293T cells confirmed these ASEs in vitro. In contrast, without new RNA species detected, the mutant mini-gene disrupted the splicing pattern of the ORF15 region, and caused loss of RPGR transcript heterogeneity. The RNA species derived from the mutant mini-gene were predominated by a minor out-of-frame transcript that was also observed in wildtype RPGR, resulting from an upstream alternative 5' splice site in exon 14. Our findings therefore provide insights into the influence of RPGR exonic mutations on alternative splicing of the ORF15 region, and the underlying molecular mechanism of RP.
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Affiliation(s)
- Yan-Shan Liu
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Joint Primate Research Center for Chronic Diseases, Jiangnan University and Guangdong Institute of Applied Biological Resources, Jiangnan University, Wuxi, Jiangsu, China; Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong, China
| | - Jia-Qi Pan
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Joint Primate Research Center for Chronic Diseases, Jiangnan University and Guangdong Institute of Applied Biological Resources, Jiangnan University, Wuxi, Jiangsu, China; Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong, China
| | - Ji-Feng Wan
- Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Chun-Yan Ren
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Joint Primate Research Center for Chronic Diseases, Jiangnan University and Guangdong Institute of Applied Biological Resources, Jiangnan University, Wuxi, Jiangsu, China; School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Zhou-Heng Xu
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Xu-Bin Pan
- Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - Ruo-Nan Gao
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Shao-Qiang Liu
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | - Jia-Li Zhang
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China
| | | | - Ji-Hong Wang
- Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, China
| | - En-Min Li
- Shantou University Medical College, Shantou, Guangdong, China
| | - Jun-Hua Rao
- Joint Primate Research Center for Chronic Diseases, Jiangnan University and Guangdong Institute of Applied Biological Resources, Jiangnan University, Wuxi, Jiangsu, China; Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong, China
| | - Ping Hou
- Jinhua Eye Hospital, Jinhua, Zhejiang, China.
| | - Jian-Huan Chen
- Laboratory of Genomic and Precision Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, Jiangsu, China; Joint Primate Research Center for Chronic Diseases, Jiangnan University and Guangdong Institute of Applied Biological Resources, Jiangnan University, Wuxi, Jiangsu, China; Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong, China.
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Fujinami K, Liu X, Ueno S, Mizota A, Shinoda K, Kuniyoshi K, Fujinami-Yokokawa Y, Yang L, Arno G, Pontikos N, Kameya S, Kominami T, Terasaki H, Sakuramoto H, Nakamura N, Kurihara T, Tsubota K, Miyake Y, Yoshiake K, Iwata T, Tsunoda K. RP2-associated retinal disorder in a Japanese cohort: Report of novel variants and a literature review, identifying a genotype-phenotype association. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:675-693. [PMID: 32875684 DOI: 10.1002/ajmg.c.31830] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 07/28/2020] [Accepted: 07/28/2020] [Indexed: 01/10/2023]
Abstract
The retinitis pigmentosa 2 (RP2) gene is one of the causative genes for X-linked inherited retinal disorder. We characterized the clinical/genetic features of four patients with RP2-associated retinal disorder (RP2-RD) from four Japanese families in a nationwide cohort. A systematic review of RP2-RD in the Japanese population was also performed. All four patients were clinically diagnosed with retinitis pigmentosa (RP). The mean age at examination was 36.5 (10-47) years, and the mean visual acuity in the right/left eye was 1.40 (0.52-2.0)/1.10 (0.52-1.7) in the logarithm of the minimum angle of resolution unit, respectively. Three patients showed extensive retinal atrophy with macular involvement, and one had central retinal atrophy. Four RP2 variants were identified, including two novel missense (p.Ser6Phe, p.Leu189Pro) and two previously reported truncating variants (p.Arg120Ter, p.Glu269CysfsTer3). The phenotypes of two patients with truncating variants were more severe than the phenotypes of two patients with missense variants. A systematic review revealed additional 11 variants, including three missense and eight deleterious (null) variants, and a statistically significant association between phenotype severity and genotype severity was revealed. The clinical and genetic spectrum of RP2-RD was illustrated in the Japanese population, identifying the characteristic features of a severe form of RP with early macular involvement.
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Affiliation(s)
- Kaoru Fujinami
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.,UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK
| | - Xiao Liu
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.,Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Atsushi Mizota
- Department of Ophthalmology, Teikyo University, Tokyo, Japan
| | - Kei Shinoda
- Department of Ophthalmology, Teikyo University, Tokyo, Japan.,Department of Ophthalmology, Saitama Medical University, Moroyama Campus, Saitama, Japan
| | - Kazuki Kuniyoshi
- Department of Ophthalmology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan
| | - Yu Fujinami-Yokokawa
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,UCL Institute of Ophthalmology, London, UK.,Department of Health Policy and Management, Keio University School of Medicine, Tokyo, Japan.,Division of Public Health, Yokokawa Clinic, Suita, Japan
| | - Lizhu Yang
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Gavin Arno
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK.,North East Thames Regional Genetics Service, UCL Great Ormond Street Institute of Child Health, NHS Foundation Trust, London, UK
| | - Nikolas Pontikos
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,UCL Institute of Ophthalmology, London, UK.,Moorfields Eye Hospital, London, UK
| | - Shuhei Kameya
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Japan
| | - Taro Kominami
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Hiroyuki Sakuramoto
- Department of Ophthalmology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan
| | - Natsuko Nakamura
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Teikyo University, Tokyo, Japan.,Department of Ophthalmology, The University of Tokyo, Tokyo, Japan
| | - Toshihide Kurihara
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Yozo Miyake
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Aichi Medical University, Nagakute, Japan.,Next vision, Kobe Eye Center, Kobe, Japan
| | - Kazutoshi Yoshiake
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Takeshi Iwata
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Kazushige Tsunoda
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
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Foote KG, Wong JJ, Boehm AE, Bensinger E, Porco TC, Roorda A, Duncan JL. Comparing Cone Structure and Function in RHO- and RPGR-Associated Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2020; 61:42. [PMID: 32343782 PMCID: PMC7401955 DOI: 10.1167/iovs.61.4.42] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Purpose To study cone structure and function in patients with retinitis pigmentosa (RP) owing to mutations in rhodopsin (RHO), expressed in rod outer segments, and mutations in the RP-GTPase regulator (RPGR) gene, expressed in the connecting cilium of rods and cones. Methods Four eyes of 4 patients with RHO mutations, 5 eyes of 5 patients with RPGR mutations, and 4 eyes of 4 normal subjects were studied. Cone structure was studied with confocal and split-detector adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral-domain optical coherence tomography. Retinal function was measured using a 543-nm AOSLO-mediated adaptive optics microperimetry (AOMP) stimulus. The ratio of sensitivity to cone density was compared between groups using the Wilcoxon rank-sum test. Results AOMP sensitivity/cone density in patients with RPGR mutations was significantly lower than normal (P< 0.001) and lower than patients with RHO mutations (P< 0.015), whereas patients with RHO mutations were similar to normal (P> 0.9). Conclusions Retinal sensitivity/cone density was lower in patients with RPGR mutations than normal and lower than patients with RHO mutations, perhaps because cones express RPGR and degenerate primarily, whereas cones in eyes with RHO mutations die secondary to rod degeneration. High-resolution microperimetry can reveal differences in cone degeneration in patients with different forms of RP.
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Zou X, Fang S, Wu S, Li H, Sun Z, Zhu T, Wei X, Sui R. Detailed comparison of phenotype between male patients carrying variants in exons 1-14 and ORF15 of RPGR. Exp Eye Res 2020; 198:108147. [PMID: 32702353 DOI: 10.1016/j.exer.2020.108147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/05/2020] [Accepted: 07/08/2020] [Indexed: 12/19/2022]
Abstract
PURPOSE To compare disease severity in detail between patients carrying variants in exons 1-14 and ORF15 of retinitis pigmentosa GTPase regulator (RPGR). METHODS Systematic next-generation sequencing data analysis, Sanger sequencing validation and segregation analysis were utilised to identify the pathogenic variants. Detailed ophthalmic examinations, including electroretinograms, fundus photography, fundus autofluorescence and optical coherence tomography were performed. Statistical analysis, including age adjustment and comparison, were performed based on cross-sectional level to compare disease severity between variants in the two RPGR variant groups. RESULTS Sixty-two variants were identified in RPGR in 86 patients from 77 unrelated families. Twenty-nine (37.7%) had variants in RPGR-exons 1-14 (group 1) and 48 (62.3%) in RPGR-ORF15 (group 2). Eighty-four patients were diagnosed with X-linked retinitis pigmentosa and only two patients with cone-rod dystrophy. LogMAR visual acuity increased 0.035 and 0.022 each year on average in group 1 and group 2, respectively. Group 2 patients had better visual acuity with a mean logMAR difference of 0.4378, which is significant after age adjustment (P < 0.01). Neither the value of log (ellipsoid zone width) nor central retinal thickness was significantly correlated with variant grouping after considering the effect of the age variable (P = 0.56 and 0.40, respectively). Spherical refractive error did not differ significantly between the two variant groups (P = 0.17). Patterns of autofluorescence included a hyperfluorescent ring at the posterior pole, diffuse hyperfluorescence in the macular area, and dark macular autofluorescence with or without fovea hyperfluorescence. The age and proportion of fundus autofluorescence patterns between the two variant groups were significantly different (P < 0.01). CONCLUSIONS Patients with variants in exons 1-14 retained less visual acuity than patients with ORF15 variants and deteriorated faster. However, the ellipsoid zone widths, central retinal thickness and refractions were comparable between the two groups. Autofluorescence pattern relates to the age and the variant grouping.
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Affiliation(s)
- Xuan Zou
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Sha Fang
- School of Statistics, Capital University of Economics and Business, Beijing, 100070, China
| | - Shijing Wu
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Hui Li
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Zixi Sun
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Tian Zhu
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Xing Wei
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China.
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42
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Maggi J, Roberts L, Koller S, Rebello G, Berger W, Ramesar R. De Novo Assembly-Based Analysis of RPGR Exon ORF15 in an Indigenous African Cohort Overcomes Limitations of a Standard Next-Generation Sequencing (NGS) Data Analysis Pipeline. Genes (Basel) 2020; 11:genes11070800. [PMID: 32679846 PMCID: PMC7396994 DOI: 10.3390/genes11070800] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 06/24/2020] [Accepted: 07/13/2020] [Indexed: 01/10/2023] Open
Abstract
RPGR exon ORF15 variants are one of the most frequent causes for inherited retinal disorders (IRDs), in particular retinitis pigmentosa. The low sequence complexity of this mutation hotspot makes it prone to indels and challenging for sequence data analysis. Whole-exome sequencing generally fails to provide adequate coverage in this region. Therefore, complementary methods are needed to avoid false positives as well as negative results. In this study, next-generation sequencing (NGS) was used to sequence long-range PCR amplicons for an IRD cohort of African ancestry. By developing a novel secondary analysis pipeline based on de novo assembly, we were able to avoid the miscalling of variants generated by standard NGS analysis tools. We identified pathogenic variants in 11 patients (13% of the cohort), two of which have not been reported previously. We provide a novel and alternative end-to-end secondary analysis pipeline for targeted NGS of ORF15 that is less prone to false positive and negative variant calls.
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Affiliation(s)
- Jordi Maggi
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8006 Zurich, Switzerland
| | - Lisa Roberts
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
| | - Samuel Koller
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
| | - George Rebello
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
| | - Wolfgang Berger
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8006 Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), University and ETH Zurich, 8006 Zurich, Switzerland
- Correspondence:
| | - Rajkumar Ramesar
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
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Lane A, Jovanovic K, Shortall C, Ottaviani D, Panes AB, Schwarz N, Guarascio R, Hayes MJ, Palfi A, Chadderton N, Farrar GJ, Hardcastle AJ, Cheetham ME. Modeling and Rescue of RP2 Retinitis Pigmentosa Using iPSC-Derived Retinal Organoids. Stem Cell Reports 2020; 15:67-79. [PMID: 32531192 PMCID: PMC7363745 DOI: 10.1016/j.stemcr.2020.05.007] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 05/13/2020] [Accepted: 05/13/2020] [Indexed: 12/18/2022] Open
Abstract
RP2 mutations cause a severe form of X-linked retinitis pigmentosa (XLRP). The mechanism of RP2-associated retinal degeneration in humans is unclear, and animal models of RP2 XLRP do not recapitulate this severe phenotype. Here, we developed gene-edited isogenic RP2 knockout (RP2 KO) induced pluripotent stem cells (iPSCs) and RP2 patient-derived iPSC to produce 3D retinal organoids as a human retinal disease model. Strikingly, the RP2 KO and RP2 patient-derived organoids showed a peak in rod photoreceptor cell death at day 150 (D150) with subsequent thinning of the organoid outer nuclear layer (ONL) by D180 of culture. Adeno-associated virus-mediated gene augmentation with human RP2 rescued the degeneration phenotype of the RP2 KO organoids, to prevent ONL thinning and restore rhodopsin expression. Notably, these data show that 3D retinal organoids can be used to model photoreceptor degeneration and test potential therapies to prevent photoreceptor cell death.
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Affiliation(s)
| | | | - Ciara Shortall
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | | | | | | | | | | | - Arpad Palfi
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Naomi Chadderton
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - G Jane Farrar
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland.
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Morizur L, Herardot E, Monville C, Ben M'Barek K. Human pluripotent stem cells: A toolbox to understand and treat retinal degeneration. Mol Cell Neurosci 2020; 107:103523. [PMID: 32634576 DOI: 10.1016/j.mcn.2020.103523] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 05/24/2020] [Accepted: 06/30/2020] [Indexed: 12/13/2022] Open
Abstract
Age-related Macular Degeneration (AMD) and Retinitis Pigmentosa (RP) are retinal degenerative disorders that dramatically damage the retina. As there is no therapeutic option for the majority of patients, vision is progressively and irremediably lost. Owing to their unlimited renewal and potency to give rise to any cell type of the human adult body, human pluripotent stem cells (hPSCs) have been extensively studied in recent years to develop more physiologically relevant in vitro cellular models. Such models open new perspectives to investigate the pathological molecular mechanisms of AMD and RP but also in drug screening. Moreover, proof-of-concept of hPSC-derived retinal cell therapy in animal models have led to first clinical trials. This review outlines the recent advances in the use of hPSCs in pathological modeling of retinal degeneration and their use in regenerative medicine. We also address the associated limitations and challenges that need to be overcome when using hPSCs.
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Affiliation(s)
- Lise Morizur
- INSERM U861, I-Stem, AFM, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France; Université Paris-Saclay, Université d'Evry, U861, 91100 Corbeil-Essonnes, France; Centre d'Etude des Cellules Souches, 91100 Corbeil-Essonnes, France
| | - Elise Herardot
- INSERM U861, I-Stem, AFM, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France; Université Paris-Saclay, Université d'Evry, U861, 91100 Corbeil-Essonnes, France
| | - Christelle Monville
- INSERM U861, I-Stem, AFM, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France; Université Paris-Saclay, Université d'Evry, U861, 91100 Corbeil-Essonnes, France.
| | - Karim Ben M'Barek
- INSERM U861, I-Stem, AFM, Institute for Stem Cell Therapy and Exploration of Monogenic Diseases, 91100 Corbeil-Essonnes, France; Université Paris-Saclay, Université d'Evry, U861, 91100 Corbeil-Essonnes, France; Centre d'Etude des Cellules Souches, 91100 Corbeil-Essonnes, France.
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Garafalo AV, Cideciyan AV, Héon E, Sheplock R, Pearson A, WeiYang Yu C, Sumaroka A, Aguirre GD, Jacobson SG. Progress in treating inherited retinal diseases: Early subretinal gene therapy clinical trials and candidates for future initiatives. Prog Retin Eye Res 2020; 77:100827. [PMID: 31899291 PMCID: PMC8714059 DOI: 10.1016/j.preteyeres.2019.100827] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 12/21/2019] [Accepted: 12/26/2019] [Indexed: 12/15/2022]
Abstract
Due to improved phenotyping and genetic characterization, the field of 'incurable' and 'blinding' inherited retinal diseases (IRDs) has moved substantially forward. Decades of ascertainment of IRD patient data from Philadelphia and Toronto centers illustrate the progress from Mendelian genetic types to molecular diagnoses. Molecular genetics have been used not only to clarify diagnoses and to direct counseling but also to enable the first clinical trials of gene-based treatment in these diseases. An overview of the recent reports of gene augmentation clinical trials by subretinal injections is used to reflect on the reasons why there has been limited success in this early venture into therapy. These first-in human experiences have taught that there is a need for advancing the techniques of delivery of the gene products - not only for refining further subretinal trials, but also for evaluating intravitreal delivery. Candidate IRDs for intravitreal gene delivery are then suggested to illustrate some of the disorders that may be amenable to improvement of remaining central vision with the least photoreceptor trauma. A more detailed understanding of the human IRDs to be considered for therapy and the calculated potential for efficacy should be among the routine prerequisites for initiating a clinical trial.
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Affiliation(s)
- Alexandra V Garafalo
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Artur V Cideciyan
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Elise Héon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Rebecca Sheplock
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Alexander Pearson
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Caberry WeiYang Yu
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada
| | - Alexander Sumaroka
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Gustavo D Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Samuel G Jacobson
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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46
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Way CM, Lima Cunha D, Moosajee M. Translational readthrough inducing drugs for the treatment of inherited retinal dystrophies. EXPERT REVIEW OF OPHTHALMOLOGY 2020. [DOI: 10.1080/17469899.2020.1762489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Christopher M Way
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Dulce Lima Cunha
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
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47
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Menghini M, Jolly JK, Nanda A, Wood L, Cehajic-Kapetanovic J, MacLaren RE. Early Cone Photoreceptor Outer Segment Length Shortening in RPGR X-Linked Retinitis Pigmentosa. Ophthalmologica 2020; 244:281-290. [PMID: 32209785 DOI: 10.1159/000507484] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/24/2020] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Introduction of retinal gene therapy requires established outcome measures along with thorough understanding of the pathophysiology. Evidence of early, thinned outer segments in RPGR X-linked retinitis pigmentosa could help understand how the level of cone photoreceptor involvement translates to visual potential. OBJECTIVE Analysis of foveal photoreceptor outer segment length in a young cohort of RPGR patients to help clarify the reason for absent maximal visual acuity seen. METHODS Case-control study of RPGR patients. Quantitative measurement of photoreceptor outer segment by OCT. RESULTS Eighteen male RPGR patients and 30 normal subjects were included. Outer segment thickness differed significantly between the RPGR and normal eyes (p < 0.0005). Mean outer segment values were 35.6 ± 2.3 µm and 35.4 ± 2.6 µm for RPGR right and left eyes, respectively. In normal eyes, the mean outer segment thickness was 61.4 ± 0.7 µm for right eyes and 62.4 ± 0.7 µm for left eyes. CONCLUSIONS Patients with RPGR X-linked retinitis pigmentosa show thinning of the foveal photoreceptor outer segment thickness early in the disease course, which could be an explanation for the lower maximum visual acuity seen. These findings must be taken into consideration when assessing efficacy outcome measures in retinal gene therapy trials.
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Affiliation(s)
- Moreno Menghini
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK,
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK,
| | - Jasleen K Jolly
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Anika Nanda
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Laura Wood
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Jasmina Cehajic-Kapetanovic
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, Oxford University, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
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Barabino A, Flamier A, Hanna R, Héon E, Freedman BS, Bernier G. Deregulation of Neuro-Developmental Genes and Primary Cilium Cytoskeleton Anomalies in iPSC Retinal Sheets from Human Syndromic Ciliopathies. Stem Cell Reports 2020; 14:357-373. [PMID: 32160518 PMCID: PMC7066374 DOI: 10.1016/j.stemcr.2020.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 02/10/2020] [Accepted: 02/11/2020] [Indexed: 01/22/2023] Open
Abstract
Ciliopathies are heterogeneous genetic diseases affecting primary cilium structure and function. Meckel-Gruber (MKS) and Bardet-Biedl (BBS) syndromes are severe ciliopathies characterized by skeletal and neurodevelopment anomalies, including polydactyly, cognitive impairment, and retinal degeneration. We describe the generation and molecular characterization of human induced pluripotent stem cell (iPSC)-derived retinal sheets (RSs) from controls, and MKS (TMEM67) and BBS (BBS10) cases. MKS and BBS RSs displayed significant common alterations in the expression of hundreds of developmental genes and members of the WNT and BMP pathways. Induction of crystallin molecular chaperones was prominent in MKS and BBS RSs suggesting a stress response to misfolded proteins. Unique to MKS photoreceptors was the presence of supernumerary centrioles and cilia, and aggregation of ciliary proteins. Unique to BBS photoreceptors was the accumulation of DNA damage and activation of the mitotic spindle checkpoint. This study reveals how combining cell reprogramming, organogenesis, and next-generation sequencing enables the elucidation of mechanisms involved in human ciliopathies.
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Affiliation(s)
- Andrea Barabino
- Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. Assomption, Montreal, QC H1T 2M4, Canada
| | - Anthony Flamier
- Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. Assomption, Montreal, QC H1T 2M4, Canada
| | - Roy Hanna
- Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. Assomption, Montreal, QC H1T 2M4, Canada
| | - Elise Héon
- Hospital for Sick Children, Department of Ophthalmology and Vision Sciences, Program of Genetics and Genome Biology, 555 University av., Toronto, ON M5G 1X8, Canada
| | - Benjamin S Freedman
- Department of Medicine, Division of Nephrology, Kidney Research Institute, and Institute of Stem Cell and Regenerative Medicine, and Department of Pathology, University of Washington School of Medicine, Seattle, WA 98109, USA.
| | - Gilbert Bernier
- Stem Cell and Developmental Biology Laboratory, Hôpital Maisonneuve-Rosemont, 5415 Boul. Assomption, Montreal, QC H1T 2M4, Canada; Department of Neurosciences, University of Montreal, Montreal, QC H3C 3J7, Canada; Department of Ophthalmology, University of Montreal, Montreal, QC H3C 3J7, Canada.
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Appelbaum T, Santana E, Aguirre GD. Critical Decrease in the Level of Axon Guidance Receptor ROBO1 in Rod Synaptic Terminals Is Followed by Axon Retraction. Invest Ophthalmol Vis Sci 2020; 61:11. [PMID: 32176262 PMCID: PMC7405958 DOI: 10.1167/iovs.61.3.11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 12/14/2019] [Indexed: 12/24/2022] Open
Abstract
Purpose To define remodeling of photoreceptor synaptic terminals and second-order retinal neurons in canine X-linked progressive retinal atrophy 1 caused by a five-nucleotide deletion in the RPGR exon ORF15. Methods Retinas of normal and mutant dogs were used for gene expression, Western blot, and immunohistochemistry. Cell-specific markers were used to examine disease-dependent retinal remodeling. Results In mutant retinas, a number of rod axon terminals retract into the outer nuclear layer. This neuritic atrophy preceded significant loss of rods and was evident early in disease. Rod bipolar and horizontal cell processes were found to extend into the outer nuclear layer, where they seemed to form contacts with the spherules of rod photoreceptors. No ectopic rewiring was observed. Because cytoskeletal reorganization was previously shown to underlie photoreceptor axon retraction, we examined normal and mutant retinas for expression of axon guidance receptors ROBO1 and ROBO2, which are known to regulate actin cytoskeleton dynamics. We found that the overall expression of both ROBO1 and ROBO2 is retained at the same level in premature and fully developed normal retinas. However, analysis of predisease and early disease retinas identified markedly decreased levels of ROBO1 in rod spherules compared with controls. In contrast, no differences in ROBO1 signals were noted in cone pedicles in normal and mutant retinas, where ROBO1 levels remained similarly low. Conclusions Depletion of ROBO1 in rod synaptic terminals correlates with the remodeling of axonal and dendritic processes in the outer retina of dogs with X-linked progressive retinal atrophy 1 and may play a role in the retraction of rod axons.
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Affiliation(s)
- Tatyana Appelbaum
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Evelyn Santana
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Gustavo D. Aguirre
- Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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Dufour VL, Cideciyan AV, Ye GJ, Song C, Timmers A, Habecker PL, Pan W, Weinstein NM, Swider M, Durham AC, Ying GS, Robinson PM, Jacobson SG, Knop DR, Chulay JD, Shearman MS, Aguirre GD, Beltran WA. Toxicity and Efficacy Evaluation of an Adeno-Associated Virus Vector Expressing Codon-Optimized RPGR Delivered by Subretinal Injection in a Canine Model of X-linked Retinitis Pigmentosa. Hum Gene Ther 2020; 31:253-267. [PMID: 31910043 DOI: 10.1089/hum.2019.297] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Applied Genetic Technologies Corporation (AGTC) is developing a recombinant adeno-associated virus (rAAV) vector AGTC-501, also designated rAAV2tYF-GRK1-hRPGRco, to treat X-linked retinitis pigmentosa (XLRP) in patients with mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene. The vector contains a codon-optimized human RPGR cDNA (hRPGRco) driven by a photoreceptor-specific promoter (G protein-coupled receptor kinase 1 [GRK1]), and is packaged in an AAV2 capsid variant with three surface tyrosine residues changed to phenylalanine (AAV2tYF). We conducted a toxicity and efficacy study of this vector administered by subretinal injection in the naturally occurring RPGR mutant (X-linked progressive retinal atrophy 2 [XLPRA2]) dog model. Sixteen RPGR mutant dogs divided into four groups of three to five animals each received either a subretinal injection of 0.07 mL of AGTC-501 at low (1.2 × 1011 vector genome [vg]/mL), mid (6 × 1011 vg/mL), or high dose (3 × 1012 vg/mL), or of vehicle control in the right eye at early-stage disease. The left eye remained untreated. Subretinal injections were well tolerated and were not associated with systemic toxicity. Electroretinography, in vivo retinal imaging, and histological analysis showed rescue of photoreceptor function and structure in the absence of ocular toxicity in the low- and mid-dose treatment groups when compared with the vehicle-treated group. The high-dose group showed evidence of both photoreceptor rescue and posterior segment toxicity. These results support the use of AGTC-501 in clinical studies with patients affected with XLRP caused by RPGR mutations and define the no-observed-adverse-effect level at 6 × 1011 vg/mL.
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Affiliation(s)
- Valérie L Dufour
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Guo-Jie Ye
- Applied Genetic Technologies Corporation, Alachua, Florida
| | - Chunjuan Song
- Applied Genetic Technologies Corporation, Alachua, Florida
| | - Adrian Timmers
- Applied Genetic Technologies Corporation, Alachua, Florida
| | - Perry L Habecker
- Department of Pathobiology, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, Pennsylvania
| | - Wei Pan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Nicole M Weinstein
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Malgorzata Swider
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Amy C Durham
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Gui-Shuang Ying
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | | | - Samuel G Jacobson
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - David R Knop
- Applied Genetic Technologies Corporation, Alachua, Florida
| | | | | | - Gustavo D Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - William A Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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