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Pungor K, Lee J, Denee T, Kambarov Y, Nissinen R, Ampeh K, Pellegrini M, Parmeggiani F. Impacts of X-linked Retinitis Pigmentosa and Patient Pathways in European Countries: Results from the Cross-sectional EXPLORE XLRP-1 Physician Survey. Adv Ther 2024; 41:3378-3395. [PMID: 38976125 PMCID: PMC11263408 DOI: 10.1007/s12325-024-02935-5] [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: 04/05/2024] [Accepted: 06/17/2024] [Indexed: 07/09/2024]
Abstract
INTRODUCTION X-linked retinitis pigmentosa (XLRP) is a rare, incurable, vision-threatening, genetic disease. In this study, we aimed to reveal the real-world burden of this disease from the viewpoint of retina specialists and geneticists involved directly in XLRP care and to identify unique insights that may not otherwise be available through typical clinical studies or health economic research. METHODS In this exploratory, cross-sectional study (EXPLORE XLRP-1), retina specialists (n = 20) and geneticists (n = 5) in France, Germany, Italy, Spain, and the UK provided anonymized insights on their experiences managing patients with XLRP (n = 80) via an online survey and 60-min telephone interview. RESULTS Survey respondents reported that patient independence decreased over time, where 37% of patients were considered "completely autonomous" at diagnosis versus 23% at the last consultation. At their last visit, 45% of patients were active in the workforce; 67% (12/18) of "completely autonomous" patients had active working status compared with 13% (1/8) of "completely dependent" patients. The average time from onset of symptoms to diagnosis was 4 years and varied among countries. In 78% of patients, XLRP was confirmed by genetic testing, the rate of which varied among countries (range, 50-94%), taking up to 6 months to receive results. Specialists identified unmet needs in XLRP management including more standardized assessments of quality of life (QoL) as well as easier and earlier access to specialists, genetic testing, patient support programs, and effective treatment options. CONCLUSIONS The diagnosis, genetic testing, and management pathways among patients with XLRP can vary considerably. There is a need for more standardized diagnosis and management pathways, and QoL assessments, due to the major impact that XLRP has on patients' lives.
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Affiliation(s)
| | | | - Tom Denee
- Janssen-Cilag BV, Breda, Netherlands
| | | | | | | | - Marco Pellegrini
- Department of Translational Medicine, University of Ferrara, Ferrara, Italy
- Department of Ophthalmology, Ospedali Privati Forlì "Villa Igea", Forlì, Italy
- Istituto Internazionale per la Ricerca e Formazione in Oftalmologia, Forlì, Italy
| | - Francesco Parmeggiani
- Department of Translational Medicine, University of Ferrara, Ferrara, Italy
- ERN-EYE Network - Center for Retinitis Pigmentosa of Veneto Region, Camposampiero Hospital, Padua, Italy
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2
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Thomas L, Cuisset L, Papon JF, Tamalet A, Pin I, Abou Taam R, Faucon C, Montantin G, Tissier S, Duquesnoy P, Dastot-Le Moal F, Copin B, Carion N, Louis B, Chantot-Bastaraud S, Siffroi JP, Mitri R, Coste A, Escudier E, Thouvenin G, Amselem S, Legendre M. Skewed X-chromosome inactivation drives the proportion of DNAAF6-defective airway motile cilia and variable expressivity in primary ciliary dyskinesia. J Med Genet 2024; 61:595-604. [PMID: 38408845 DOI: 10.1136/jmg-2023-109700] [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: 10/19/2023] [Accepted: 02/10/2024] [Indexed: 02/28/2024]
Abstract
BACKGROUND Primary ciliary dyskinesia (PCD) is a rare airway disorder caused by defective motile cilia. Only male patients have been reported with pathogenic mutations in X-linked DNAAF6, which result in the absence of ciliary dynein arms, whereas their heterozygous mothers are supposedly healthy. Our objective was to assess the possible clinical and ciliary consequences of X-chromosome inactivation (XCI) in these mothers. METHODS XCI patterns of six mothers of male patients with DNAAF6-related PCD were determined by DNA-methylation studies and compared with their clinical phenotype (6/6 mothers), as well as their ciliary phenotype (4/6 mothers), as assessed by immunofluorescence and high-speed videomicroscopy analyses. The mutated X chromosome was tracked to assess the percentage of cells with a normal inactivated DNAAF6 allele. RESULTS The mothers' phenotypes ranged from absence of symptoms to mild/moderate or severe airway phenotypes, closely reflecting their XCI pattern. Analyses of the symptomatic mothers' airway ciliated cells revealed the coexistence of normal cells and cells with immotile cilia lacking dynein arms, whose ratio closely mirrored their XCI pattern. CONCLUSION This study highlights the importance of searching for heterozygous pathogenic DNAAF6 mutations in all female relatives of male PCD patients with a DNAAF6 defect, as well as in females consulting for mild chronic respiratory symptoms. Our results also demonstrate that about one-third-ranging from 20% to 50%-normal ciliated airway cells sufficed to avoid severe PCD, a result paving the way for gene therapy.
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Affiliation(s)
- Lucie Thomas
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
| | - Laurence Cuisset
- Service de Médecine Génomique, Assistance Publique Hôpitaux de Paris (AP-HP), Université de Paris, Hôpital Cochin, Paris, F-75014, France
| | - Jean-Francois Papon
- Service d'Oto-Rhino-Laryngologie et de Chirurgie Cervico-Faciale, AP-HP, Hôpital Bicêtre, Le Kremlin-Bicêtre, F-94270, France
- Institut Mondor de Recherche Biomédicale, Université Paris-Est Créteil, Inserm U955, CNRS ERL7240, Hôpital Henri-Mondor, Créteil, F-94010, France
| | - Aline Tamalet
- Département de Pneumologie Pédiatrique, Centre National de Référence des Maladies Respiratoires Rares RespiRare, AP-HP, Sorbonne Université, Hôpital Armand-Trousseau Hospital, Paris, F-75012, France
| | - Isabelle Pin
- Pédiatrie, CHU Grenoble Alpes, Grenoble, F-38500, France
| | - Rola Abou Taam
- Service de Pneumologie et Allergologie Pédiatriques, AP-HP, Hôpital Necker-Enfants Malades, Paris, F-75015, France
| | - Catherine Faucon
- Service d'Anatomopathologie, Laboratoire de Microscopie Electronique, Centre Hospitalier Intercommunal de Créteil, Créteil, F-94000, France
| | - Guy Montantin
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
| | - Sylvie Tissier
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
| | - Philippe Duquesnoy
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
| | | | - Bruno Copin
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
| | - Nathalie Carion
- Service de Médecine Génomique, Assistance Publique Hôpitaux de Paris (AP-HP), Université de Paris, Hôpital Cochin, Paris, F-75014, France
| | - Bruno Louis
- Institut Mondor de Recherche Biomédicale, Université Paris-Est Créteil, Inserm U955, CNRS ERL7240, Hôpital Henri-Mondor, Créteil, F-94010, France
| | - Sandra Chantot-Bastaraud
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique chromosomique, AP-HP, Hôpital Trousseau, Paris, F-75012, France
| | - Jean-Pierre Siffroi
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique chromosomique, AP-HP, Hôpital Trousseau, Paris, F-75012, France
| | - Rana Mitri
- Service d'Anatomopathologie, Laboratoire de Microscopie Electronique, Centre Hospitalier Intercommunal de Créteil, Créteil, F-94000, France
| | - André Coste
- Institut Mondor de Recherche Biomédicale, Université Paris-Est Créteil, Inserm U955, CNRS ERL7240, Hôpital Henri-Mondor, Créteil, F-94010, France
- Service d'ORL et de Chirurgie Cervico-Faciale, AP-HP, Hôpital Henri-Mondor, Centre Hospitalier Intercommunal de Créteil, Créteil, F-94000, France
| | - Estelle Escudier
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
| | - Guillaume Thouvenin
- Département de Pneumologie Pédiatrique, Centre National de Référence des Maladies Respiratoires Rares RespiRare, AP-HP, Sorbonne Université, Hôpital Armand-Trousseau Hospital, Paris, F-75012, France
| | - Serge Amselem
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
| | - Marie Legendre
- Childhood Genetic Diseases, Sorbonne Université, Inserm, Hôpital Armand-Trousseau, Paris, F-75012, France
- Génétique moléculaire, AP-HP, Hôpital Armand-Trousseau, Paris, F-75012, Paris
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Seliniotaki AK, Ververi A, Koukoula S, Efstathiou G, Gerou S, Ziakas N, Mataftsi A. Female carrier of RPGR mutation presenting with high myopia. Ophthalmic Genet 2024; 45:159-163. [PMID: 37489109 DOI: 10.1080/13816810.2023.2237571] [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: 01/28/2023] [Accepted: 07/12/2023] [Indexed: 07/26/2023]
Abstract
BACKGROUND Inherited retinopathies can initially present with high refractive error in the first decade of life, before accompanying signs or symptoms are evident. CASE PRESENTATION A 4-year-old girl with high myopia (S-12.00 C-4.00 × 20 in the right and S-14.50 C-2.75 × 160 in the left eye), moderate visual acuity (0.3 logMAR in the right and 0.4 logMAR in the left eye), and left esotropia, presented with unremarkable past medical history and no family history of high refractive error or low vision. In optical coherence tomography imaging, macular thinning was evident, while morphology was normal. Full-field electroretinogram revealed normal implicit time recordings with reduced amplitudes in scotopic and photopic conditions. Fundus autofluorescence showed a radial pattern in both eyes. During a 5-year follow-up, significant myopia progression ensued (S-17.25 C-3.00 × 20 in the right and S-17.25 C-2.00 × 160 in the left eye), with a corresponding increase in axial length and an unchanged visual acuity. Whole-exome sequencing revealed a heterozygous termination codon variant c.212C>G (p.Ser71Ter) in RPGR, considered to be pathogenic. Segregation analysis precluded the variation in the mother and sister. A random pattern of X-chromosome inactivation was detected in the proband, without X-chromosome inactivation deviation. CONCLUSION This is the second report associating this specific RPGR mutation with high myopia and the first report to identify it in a female proband. This case provides additional evidence on the genotypic-phenotypic correlation between RPGR c.212C>G mutation and high myopia.
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Affiliation(s)
- Aikaterini K Seliniotaki
- 2nd Department of Ophthalmology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Athina Ververi
- Genetic Unit, 1st Gynecological & Obstetrics Department, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | - Georgios Efstathiou
- Analysi Biopathological Diagnostic Research Laboratories, Thessaloniki, Greece
| | - Spyridon Gerou
- Analysi Biopathological Diagnostic Research Laboratories, Thessaloniki, Greece
| | - Nikolaos Ziakas
- 2nd Department of Ophthalmology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Asimina Mataftsi
- 2nd Department of Ophthalmology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
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4
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Park H, Hwang S, Kim SJ. Severe Phenotypic Presentation of RPGR-associated X-linked Retinitis Pigmentosa in Female Carriers: Two Case Reports. KOREAN JOURNAL OF OPHTHALMOLOGY 2024; 38:164-166. [PMID: 38351481 PMCID: PMC11016683 DOI: 10.3341/kjo.2023.0119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 01/04/2024] [Indexed: 04/16/2024] Open
Affiliation(s)
- Hansol Park
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul,
Korea
| | - Sungsoon Hwang
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul,
Korea
- Department of Clinical Research Design and Evaluation, Samsung Advanced Institute for Health Sciences and Technology (SAIHST), Sungkyunkwan University, Seoul,
Korea
| | - Sang Jin Kim
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul,
Korea
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Huang L, Lai Y, Sun L, Li S, Ding X. HIGH MYOPIA IS COMMON IN PATIENTS WITH X-LINKED RETINOPATHIES: Myopic Maculopathy Analysis. Retina 2024; 44:117-126. [PMID: 38117582 DOI: 10.1097/iae.0000000000003934] [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] [Indexed: 12/22/2023]
Abstract
PURPOSE High myopia can occur as a single or syndromic condition. The aim of this study was to evaluate the refractive error and myopic maculopathy in patients with X-linked retinopathies. METHODS Whole exome sequencing, Sanger sequencing, and comprehensive ocular examinations were performed in patients with X-linked retinopathies. RESULTS A total of 17 patients were recruited, including six with CACNA1F, seven with RPGR, three with NYX, and one with OPN1MW mutations. The diagnoses were congenital stationary night blindness (6), cone-rod dystrophy (4), retinitis pigmentosa (4), achromatopsia (1), Leber congenital amaurosis (1), and myopia (1). Myopia was present in 88.2% patients, and 64.7% patients had high myopia. Gene analysis showed that high myopia was present in 80% patients with CACNA1F, 100% patients with NYX, and 57.1% patients with RPGR mutations. In the ATN classification, 64.7% of the patients were A1T0N0 and 35.3% were A0T0N0. The refractive errors progressed over time, even in patients with congenital stationary night blindness. Two females with heterozygous de novo RPGR mutations presented with retinitis pigmentosa or cone rod dystrophy combined with high myopia. CONCLUSION High myopia is common in patients with X-linked retinopathies, and myopic maculopathy was only mild atrophy without traction and neovascularization.
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Affiliation(s)
- Li Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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6
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Usman M, Jüschke C, Song F, Kastrati D, Owczarek-Lipska M, Eilers J, Pauleikhoff L, Lange C, Neidhardt J. Skewed X-inactivation is associated with retinal dystrophy in female carriers of RPGR mutations. Life Sci Alliance 2023; 6:e202201814. [PMID: 37541846 PMCID: PMC10403639 DOI: 10.26508/lsa.202201814] [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: 11/09/2022] [Revised: 07/18/2023] [Accepted: 07/24/2023] [Indexed: 08/06/2023] Open
Abstract
Progressive degeneration of rod and cone photoreceptors frequently is caused by mutations in the X-chromosomal gene Retinitis Pigmentosa GTPase Regulator (RPGR). Males hemizygous for a RPGR mutation often are affected by Retinitis Pigmentosa (RP), whereas female mutation carriers only occasionally present with severe RP phenotypes. The underlying pathomechanism leading to RP in female carriers is not well understood. Here, we analyzed a three-generation family in which two of three female carriers of a nonsense RPGR mutation presented with RP. Among two cell lines derived from the same female family members, differences were detected in RPGR transcript expression, in localization of RPGR along cilia, as well as in primary cilium length. Significantly, these differences correlated with alterations in X-chromosomal inactivation patterns found in the patient-derived cell lines from females. In summary, our data suggest that skewed X-chromosomal inactivation is an important factor that determines the disease manifestation of RP among female carriers of pathogenic sequence alterations in the RPGR gene.
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Affiliation(s)
- Muhammad Usman
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Christoph Jüschke
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Fei Song
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Dennis Kastrati
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Marta Owczarek-Lipska
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
- Junior Research Group, Genetics of Childhood Brain Malformations, School of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany
| | - Jannis Eilers
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
| | - Laurenz Pauleikhoff
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Clemens Lange
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
- Ophtha-Lab, Department of Ophthalmology at St. Franziskus Hospital, Muenster, Germany
| | - John Neidhardt
- Human Genetics, Medical Faculty, School of Medicine and Health Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany
- Research Center Neurosensory Science, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
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7
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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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9
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Raparia E, Ballios BG, Place EM, Husain D, Huckfeldt RM. RP2 X-LINKED RETINITIS PIGMENTOSA CARRIER STATE PRESENTING WITH VASCULAR LEAKAGE AND UNILATERAL MACULAR ATROPHY. Retin Cases Brief Rep 2023; 17:533-537. [PMID: 37643038 PMCID: PMC10448798 DOI: 10.1097/icb.0000000000001239] [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] [Indexed: 08/31/2023]
Abstract
PURPOSE We describe the unusual clinical presentation of a 33-year-old woman subsequently identified as a carrier of RP2-associated X-linked retinitis pigmentosa. METHODS Case report. RESULTS A 33-year-old woman without a known family history of retinal disease presented with unilateral reduced visual acuity and central scotoma in the left eye. Examination showed underlying macular atrophy in the left eye and a bilateral tapetal-like reflex. Full-field electroretinogram was abnormal in the left eye but normal in the right eye. Notable findings on wide-field imaging included bilateral peripheral vascular leakage on fluorescein angiography and a bilaterally symmetric radial pattern of hyperfluorescence on fundus autofluorescence. Genetic testing demonstrated a pathogenic variant in the gene RP2 confirming that she was a carrier of X-linked retinitis pigmentosa. CONCLUSION We describe clinical features of the carrier state of RP2-XLRP and expand potential findings to include peripheral vascular leakage. This case highlights the importance of awareness of the carrier state, particularly if a family history cannot be provided.
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Affiliation(s)
- Eva Raparia
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts; and
| | - Brian G. Ballios
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts; and
- Department of Ophthalmology and Vision Sciences, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Emily M. Place
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts; and
| | - Deeba Husain
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts; and
| | - Rachel M. Huckfeldt
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts; and
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Johansson J, Lidéus S, Höijer I, Ameur A, Gudmundsson S, Annerén G, Bondeson ML, Wilbe M. A novel quantitative targeted analysis of X-chromosome inactivation (XCI) using nanopore sequencing. Sci Rep 2023; 13:12856. [PMID: 37553382 PMCID: PMC10409790 DOI: 10.1038/s41598-023-34413-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 04/29/2023] [Indexed: 08/10/2023] Open
Abstract
X-chromosome inactivation (XCI) analyses often assist in diagnostics of X-linked traits, however accurate assessment remains challenging with current methods. We developed a novel strategy using amplification-free Cas9 enrichment and Oxford nanopore technologies sequencing called XCI-ONT, to investigate and rigorously quantify XCI in human androgen receptor gene (AR) and human X-linked retinitis pigmentosa 2 gene (RP2). XCI-ONT measures methylation over 116 CpGs in AR and 58 CpGs in RP2, and separate parental X-chromosomes without PCR bias. We show the usefulness of the XCI-ONT strategy over the PCR-based golden standard XCI technique that only investigates one or two CpGs per gene. The results highlight the limitations of using the golden standard technique when the XCI pattern is partially skewed and the advantages of XCI-ONT to rigorously quantify XCI. This study provides a universal XCI-method on DNA, which is highly valuable in clinical and research framework of X-linked traits.
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Affiliation(s)
- Josefin Johansson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Sarah Lidéus
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Ida Höijer
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Adam Ameur
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Sanna Gudmundsson
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Göran Annerén
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Marie-Louise Bondeson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden
| | - Maria Wilbe
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Husargatan 3, Box 815, SE-751 08, Uppsala, Sweden.
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11
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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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12
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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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13
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Wang Y, Sun W, Xiao X, Jiang Y, Ouyang J, Wang J, Yi Z, Li S, Jia X, Wang P, Hejtmancik JF, Zhang Q. Unique Haplotypes in OPN1LW as a Common Cause of High Myopia With or Without Protanopia: A Potential Window Into Myopic Mechanism. Invest Ophthalmol Vis Sci 2023; 64:29. [PMID: 37097228 PMCID: PMC10148663 DOI: 10.1167/iovs.64.4.29] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023] Open
Abstract
Purpose Specific haplotypes (LVAVA, LIVVA, and LIAVA) formed by five polymorphisms (p.L153M, p.V171I, p.A174V, p.I178V, and p.S180A in exon 3 of OPN1LW) that cause partial or complete exon skipping have been reported as unique genetic causes of high myopia with or without colorblindness. This study aimed to identify the contribution of OPN1LW to early-onset high myopia (eoHM) and the molecular basis underlying eoHM with or without colorblindness. Methods Comparative analysis of exome sequencing data was conducted for 1226 families with eoHM and 9304 families with other eye conditions. OPN1LW variants detected by targeted or whole exome sequencing were confirmed by long-range amplification and Sanger sequencing, together with segregation analysis. The clinical data were thoroughly analyzed. Results Unique haplotypes and truncation variants in OPN1LW were detected exclusively in 68 of 1226 families with eoHM but in none of the 9304 families with other visual diseases (P = 1.63 × 10-63). Four classes of variants were identified: haplotypes causing partial splicing defects in OPN1LW (LVAVA or LIVVA in 31 families), LVAVA in OPN1LW-OPN1MW hybrid gene (in 3 families), LIAVA in OPN1LW (in 29 families), and truncations in OPN1LW (in 5 families). The first class causes partial loss of red photopigments, whereas the latter three result in complete loss of red photopigments. This is different from the replacement of red with green owing to unequal re-arrangement causing red-green colorblindness alone. Of the 68 families, 42 affected male patients (31 families) with the first class of variants (LVAVA or LIVVA in OPN1LW) had eoHM alone, whereas 37 male patients with the latter 3 classes had eoHM with protanopia. Adaptive optics retinal imaging demonstrated reduced cone regularity and density in men with eoHM caused by OPN1LW variants compared to those patients with eoHM and without OPN1LW variants. Conclusion Based on the 68 families with unique variants in OPN1LW, our study provides firm evidence that the two different phenotypes (eoHM with or without colorblindness) are caused by two different classes of variants (partial splicing-effect haplotypes or complete splicing-effect haplotypes/truncation variants, respectively). The contribution of OPN1LW to eoHM (isolated and syndromic) was characterized by OPN1LW variants found in 5.5% (68/1226) of the eoHM families, making it the second most common cause of monogenic eoHM alone (2.4%) and a frequent cause of syndromic monogenic eoHM with colorblindness. Such haplotypes, in which each individual variant alone is considered a benign polymorphism, are potential candidates for other hereditary diseases with causes of missing genetic defects.
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Affiliation(s)
- Yingwei Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yi Jiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jiamin Ouyang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Junwen Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Zhen Yi
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoyun Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Panfeng Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - J Fielding Hejtmancik
- Ophthalmic Molecular Genetics Section, Ophthalmic Genetics and Visual Function Branch, National Eye Institute, Rockville, Maryland, United States
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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14
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Marques JP, Pinheiro R, Carvalho AL, Raimundo M, Soares M, Melo P, Murta J, Saraiva J, Silva R. Genetic spectrum, retinal phenotype, and peripapillary RNFL thickness in RPGR heterozygotes. Graefes Arch Clin Exp Ophthalmol 2023; 261:867-878. [PMID: 36050475 DOI: 10.1007/s00417-022-05809-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 08/01/2022] [Accepted: 08/10/2022] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Phenotypic heterogeneity with variable severity has been reported in female carriers of retinitis pigmentosa GTPase regulator (RPGR) mutations, including a male-type phenotype. A phenomenon not fully understood is peripapillary retinal nerve fiber layer (pRNFL) thickening in male patients with RPGR-associated X-linked retinitis pigmentosa, especially in the temporal sector. We aim to describe the genetic spectrum, retinal phenotypes, and pRNFL thickness in a cohort of Caucasian RPGR-mutation heterozygotes. METHODS A cross-sectional study was conducted at an inherited retinal degeneration (IRD) reference center in Portugal. Female patients heterozygous for clinically significant RPGR variants were identified using the IRD-PT registry. A complete ophthalmologic examination was performed, complemented by macular and peripapillary spectral domain optical coherence tomography (SD-OCT), ultra-widefield color fundus photography (UW-CFP), and ultra-widefield fundus autofluorescence (UW-FAF). The retinal phenotypes were graded according to previously described classifications. The pRNFL thickness across the superior, inferior, nasal, and temporal quadrants was compared to the Spectralis® RNFL age-adjusted reference database. RESULTS Forty-eight eyes from 24 females (10 families) were included in the study. Genetic analysis yielded 8 distinct clinically significant frameshift variants in RPGR gene, 3 of which herein reported for the first time. No association was found between mutation location and best-corrected visual acuity (BCVA) or retinal phenotype. Age was associated with worse BCVA and more advanced phenotypes on SD-OCT, UW-CFP, and UW-FAF. Seven women (29.17%) presented a male-type phenotype on UW-FAF in at least one eye. An association was found between UW-FAF and pRNFL thickness in the temporal sector (p = 0.003), with the most advanced fundus autofluorescence phenotypes showing increased pRNFL thickness in this sector. CONCLUSION This study expands the genetic landscape of RPGR-associated disease by reporting 3 novel clinically significant variants. We have shown that clinically severe phenotypes are not uncommon among female carriers. Furthermore, we provide novel insights into pRNFL changes observed in RPGR heterozygotes that mimic what has been reported in male patients.
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Affiliation(s)
- João Pedro Marques
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal. .,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal. .,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal. .,Centro de Responsabilidade Integrado de Oftalmologia (CRIO), Centro Hospitalar e Universitário de Coimbra (CHUC), Praceta Prof. Mota Pinto, 3000-075, Coimbra, Portugal.
| | - Rosa Pinheiro
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Ana Luísa Carvalho
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,Medical Genetics Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,University Clinic of Medical Genetics, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Miguel Raimundo
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Mário Soares
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Pedro Melo
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Joaquim Murta
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Jorge Saraiva
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Medical Genetics, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal.,University Clinic of Pediatrics, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
| | - Rufino Silva
- Ophthalmology Unit, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.,Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal.,University Clinic of Ophthalmology, Faculty of Medicine, University of Coimbra (FMUC), Coimbra, Portugal
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15
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Peter VG, Kaminska K, Santos C, Quinodoz M, Cancellieri F, Cisarova K, Pescini Gobert R, Rodrigues R, Custódio S, Paris LP, Sousa AB, Coutinho Santos L, Rivolta C. The first genetic landscape of inherited retinal dystrophies in Portuguese patients identifies recurrent homozygous mutations as a frequent cause of pathogenesis. PNAS NEXUS 2023; 2:pgad043. [PMID: 36909829 PMCID: PMC10003751 DOI: 10.1093/pnasnexus/pgad043] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 02/15/2023]
Abstract
Inherited retinal diseases (IRDs) are a group of ocular conditions characterized by an elevated genetic and clinical heterogeneity. They are transmitted almost invariantly as monogenic traits. However, with more than 280 disease genes identified so far, association of clinical phenotypes with genotypes can be very challenging, and molecular diagnosis is essential for genetic counseling and correct management of the disease. In addition, the prevalence and the assortment of IRD mutations are often population-specific. In this work, we examined 230 families from Portugal, with individuals suffering from a variety of IRD diagnostic classes (270 subjects in total). Overall, we identified 157 unique mutations (34 previously unreported) in 57 distinct genes, with a diagnostic rate of 76%. The IRD mutational landscape was, to some extent, different from those reported in other European populations, including Spanish cohorts. For instance, the EYS gene appeared to be the most frequently mutated, with a prevalence of 10% among all IRD cases. This was, in part, due to the presence of a recurrent and seemingly founder mutation involving the deletion of exons 13 and 14 of this gene. Moreover, our analysis highlighted that as many as 51% of our cases had mutations in a homozygous state. To our knowledge, this is the first study assessing a cross-sectional genotype-phenotype landscape of IRDs in Portugal. Our data reveal a rather unique distribution of mutations, possibly shaped by a small number of rare ancestral events that have now become prevalent alleles in patients.
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Affiliation(s)
- Virginie G Peter
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel 4031, Switzerland.,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland.,Department of Ophthalmology, Inselspital, Bern University Hospital, Bern 3010, Switzerland
| | - Karolina Kaminska
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel 4031, Switzerland.,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Cristina Santos
- Department of Ophthalmology, Instituto de Oftalmologia Dr Gama Pinto (IOGP), Lisbon 1169-019, Portugal.,iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade NOVA de Lisboa, Lisbon 1169-056, Portugal
| | - Mathieu Quinodoz
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel 4031, Switzerland.,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland.,Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
| | - Francesca Cancellieri
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel 4031, Switzerland.,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland
| | - Katarina Cisarova
- Department of Computational Biology, University of Lausanne, Lausanne 1015, Switzerland
| | | | - Raquel Rodrigues
- Department of Medical Genetics, Hospital Santa Maria, Centro Hospitalar Universitário Lisboa Norte (CHULN), Lisbon 1649-035, Portugal
| | - Sónia Custódio
- Department of Medical Genetics, Hospital Santa Maria, Centro Hospitalar Universitário Lisboa Norte (CHULN), Lisbon 1649-035, Portugal
| | - Liliana P Paris
- Department of Ophthalmology, Instituto de Oftalmologia Dr Gama Pinto (IOGP), Lisbon 1169-019, Portugal
| | - Ana Berta Sousa
- Department of Medical Genetics, Hospital Santa Maria, Centro Hospitalar Universitário Lisboa Norte (CHULN), Lisbon 1649-035, Portugal.,Laboratory of Basic Immunology, Faculty of Medicine, University of Lisbon, Lisbon 1649-028, Portugal
| | - Luisa Coutinho Santos
- Department of Ophthalmology, Instituto de Oftalmologia Dr Gama Pinto (IOGP), Lisbon 1169-019, Portugal
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel 4031, Switzerland.,Department of Ophthalmology, University of Basel, Basel 4031, Switzerland.,Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
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16
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Martinez-Fernandez de la Camara C, Cehajic-Kapetanovic J, MacLaren RE. Emerging gene therapy products for RPGR-associated X-linked retinitis pigmentosa. Expert Opin Emerg Drugs 2022; 27:431-443. [PMID: 36562395 DOI: 10.1080/14728214.2022.2152003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Mutations in the RPGR gene are responsible for one of the most prevalent and severe types of retinitis pigmentosa. Gene therapy has shown great promise to treat inherited retinal diseases, and currently, four RPGR gene therapy vectors are being evaluated in clinical trials. AREAS COVERED This manuscript reviews the gene therapy products that are in development for X-linked retinitis pigmentosa caused by mutations in RPGR, and the challenges that scientists and clinicians have faced. EXPERT OPINION The development of a gene therapy product for RPGR-associated retinal degeneration has been a great challenge due to the incomplete understanding of the underlying genetics and mechanism of action of RPGR, and on the other hand, due to the instability of the RPGR gene. Three of the four gene therapy vectors currently in clinical trials include a codon-optimized version of the human RPGR sequence, and the other vector contains a shortened version of the human RPGR. To date, the only Phase I/II results published in a peer-reviewed journal demonstrate a good safety profile and an improvement in the visual field using a codon optimized version of RPGRORF15.
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Affiliation(s)
- Cristina Martinez-Fernandez de la Camara
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West Wing, Headley Way, OX3 9DU, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, West Wing, Headley Way, OX3 9DU, Oxford, UK
| | - Jasmina Cehajic-Kapetanovic
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West Wing, Headley Way, OX3 9DU, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, West Wing, Headley Way, OX3 9DU, Oxford, UK
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, John Radcliffe Hospital, Level 5 & 6, West Wing, Headley Way, OX3 9DU, Oxford, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, West Wing, Headley Way, OX3 9DU, Oxford, UK
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17
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Mansouri V. X-Linked Retinitis Pigmentosa Gene Therapy: Preclinical Aspects. Ophthalmol Ther 2022; 12:7-34. [PMID: 36346573 PMCID: PMC9641696 DOI: 10.1007/s40123-022-00602-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 10/17/2022] [Indexed: 11/11/2022] Open
Abstract
The most common inherited eye disease is retinitis pigmentosa (RP). X-linked RP (XLRP) is one of the most severe types of RP, with a considerable disease burden. Patients with XLRP experience a decrease in their vision and become blind in their 4th decade of life, causing much morbidity after starting a rather normal life. Treatment of XLRP remains challenging, and current treatments are not effective enough in restoring vision. Gene therapy of XLRP, capable of restoring the functional RPGR gene, showed promising results in preclinical studies and clinical trials; however, to date, no approved product has entered the market. The development of a gene therapy product needs through preliminary assessment of the drug in animal models before administration to humans. In this article, we reviewed the genetic pathology of XLRP, along with the preclinical aspects of the XLRP gene therapy, animal models, associated assessments, and future challenges and directions.
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Affiliation(s)
- Vahid Mansouri
- Gene Therapy Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
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18
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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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19
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Mihailovic N, Schimpf-Linzenbold S, Sattler I, Eter N, Heiduschka P. The first reported case of a deletion of the entire RPGR gene in a family with X-linked retinitis pigmentosa. Ophthalmic Genet 2022; 43:679-684. [PMID: 35652150 DOI: 10.1080/13816810.2022.2083181] [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: 10/18/2022]
Abstract
Clinical phenotypes of a patient with a deletion of the entire RPGR gene have not been described in the literature yet. We hereby report a new mutation in a family of X-linked retinitis pigmentosa (×lRP), showing the deletion of the entire RPGR gene. Gene therapy for inherited retinal diseases holds great promise; however, so far there has been no approved treatment of RPGR-mediated retinitis pigmentosa. The presented evidence of genotype-phenotype correlation may be useful for genetic diagnosis or even genetic treatment in the near future.
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Affiliation(s)
- Nataša Mihailovic
- Department of Ophthalmology, University of Muenster Medical Center, Muenster, Germany.,Department of Ophthalmology, Klinikum Fulda, University of Marburg Campus Fulda, Fulda, Germany
| | | | - Inga Sattler
- Zentrum für Humangenetik Tübingen, Praxis fuer Humangenetik und CeGaT GmbH, Tuebingen, Germany
| | - Nicole Eter
- Department of Ophthalmology, University of Muenster Medical Center, Muenster, Germany
| | - Peter Heiduschka
- Department of Ophthalmology, University of Muenster Medical Center, Muenster, Germany
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20
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Gerussi A, Caime C, Binatti E, Cristoferi L, Asselta R, Gershwin EM, Invernizzi P. X marks the spot in autoimmunity. Expert Rev Clin Immunol 2022; 18:429-437. [PMID: 35349778 DOI: 10.1080/1744666x.2022.2060203] [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: 11/04/2022]
Abstract
INTRODUCTION Autoimmune diseases mostly affect females. Besides hormones, several factors related to chromosome X have been called in action to explain this sex predominance. AREAS COVERED This paper provides an overview on the role of chromosome X (chrX) in explaining why females have higher susceptibility to autoimmunity. The work outlines some essential concepts regarding chrX inactivation, escape from chrX inactivation and the evolutionary history of chrX. In addition, we will discuss the concept of gene escape in immune cells, with examples related to specific X-linked genes and autoimmune diseases. EXPERT OPINION There is growing evidence that many genes present on chrX escape inactivation, and some of them have significant immune-mediated functions. In immune cells of female individuals the escape of these genes is not constant, but the knowledge of the mechanisms controlling this plasticity are not completely understood. Future studies aimed at the characterization of these modifications at single-cell resolution, together with conformational 3D studies of the inactive X chromosome, will hopefully help to fill this gap of knowledge.
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Affiliation(s)
- Alessio Gerussi
- Division of Gastroenterology, Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,European Reference Network on Hepatological Diseases (ERN RARE-LIVER), San Gerardo Hospital, Monza, Italy
| | - Chiara Caime
- Division of Gastroenterology, Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,European Reference Network on Hepatological Diseases (ERN RARE-LIVER), San Gerardo Hospital, Monza, Italy
| | - Eleonora Binatti
- Division of Gastroenterology, Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,European Reference Network on Hepatological Diseases (ERN RARE-LIVER), San Gerardo Hospital, Monza, Italy
| | - Laura Cristoferi
- Division of Gastroenterology, Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,European Reference Network on Hepatological Diseases (ERN RARE-LIVER), San Gerardo Hospital, Monza, Italy
| | - Rosanna Asselta
- Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Italy.,Humanitas Clinical and Research Center, IRCCS, Rozzano, Italy
| | - Eric M Gershwin
- Division of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, Davis, CA, USA
| | - Pietro Invernizzi
- Division of Gastroenterology, Center for Autoimmune Liver Diseases, Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy.,European Reference Network on Hepatological Diseases (ERN RARE-LIVER), San Gerardo Hospital, Monza, Italy
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21
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Daruich A, Munier FL. Phenotype of Coats disease in females. BMJ Open Ophthalmol 2022; 7:e000883. [PMID: 35141419 PMCID: PMC8819807 DOI: 10.1136/bmjophth-2021-000883] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 01/18/2022] [Indexed: 12/03/2022] Open
Abstract
Objective To determine whether the clinical presentation of Coats disease differs between males and females. Methods and analysis Records of patients diagnosed with Coats disease at a single institution were retrospectively reviewed. Demographic data, main reason for initial consultation, comprehensive ocular examination at diagnosis and modalities of treatments during the follow-up were recorded. Results Records from 114 patients with Coats disease were analysed. Ninety-eight patients (86%) were male and 16 (14%) female. Mean age at diagnosis was 6.2 years±6.1 in males and 7.4 years±4.7 in females. The main initial reason for consultation was strabismus in males and decreased visual acuity in females. Stage severity at diagnosis was similar in the two groups with half of the patients presenting with stage 2B2 or lower. The extension of peripheral retinal telangiectasia was also similar (mean: 6.2±3.4 and 5.8±4.0, respectively), as was the extension of intraretinal exudation (mean: 5.0±4.5 and 5.8±4.4) and the frequency of a subfoveal nodule at diagnosis (40% vs 30%, respectively). There was no distinction between the number of laser photocoagulation or cryotherapy sessions required for both groups during the follow-up. Conclusions Coats disease presentation does not differ between genders despite being much rarer in females. We propose a pathogenic mechanism accounting for the gender-dependent incidence combined with gender-independent expressivity of Coats disease.
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Affiliation(s)
- Alejandra Daruich
- Ophthalmology Department, Hôpital Necker-Enfants Malades, AP-HP, Université de Paris, Paris. INSERM, Centre de Recherche des Cordeliers, Team 17, Paris, France
| | - Francis L Munier
- Ophthalmology Department, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
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22
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Fenner BJ, Tan TE, Barathi AV, Tun SBB, Yeo SW, Tsai ASH, Lee SY, Cheung CMG, Chan CM, Mehta JS, Teo KYC. Gene-Based Therapeutics for Inherited Retinal Diseases. Front Genet 2022; 12:794805. [PMID: 35069693 PMCID: PMC8782148 DOI: 10.3389/fgene.2021.794805] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 12/14/2021] [Indexed: 12/14/2022] Open
Abstract
Inherited retinal diseases (IRDs) are a heterogenous group of orphan eye diseases that typically result from monogenic mutations and are considered attractive targets for gene-based therapeutics. Following the approval of an IRD gene replacement therapy for Leber's congenital amaurosis due to RPE65 mutations, there has been an intensive international research effort to identify the optimal gene therapy approaches for a range of IRDs and many are now undergoing clinical trials. In this review we explore therapeutic challenges posed by IRDs and review current and future approaches that may be applicable to different subsets of IRD mutations. Emphasis is placed on five distinct approaches to gene-based therapy that have potential to treat the full spectrum of IRDs: 1) gene replacement using adeno-associated virus (AAV) and nonviral delivery vectors, 2) genome editing via the CRISPR/Cas9 system, 3) RNA editing by endogenous and exogenous ADAR, 4) mRNA targeting with antisense oligonucleotides for gene knockdown and splicing modification, and 5) optogenetic approaches that aim to replace the function of native retinal photoreceptors by engineering other retinal cell types to become capable of phototransduction.
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Affiliation(s)
- Beau J Fenner
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | - Tien-En Tan
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | | | - Sai Bo Bo Tun
- Singapore Eye Research Institute, Singapore, Singapore
| | - Sia Wey Yeo
- Singapore Eye Research Institute, Singapore, Singapore
| | - Andrew S H Tsai
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | - Shu Yen Lee
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | - Chui Ming Gemmy Cheung
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | - Choi Mun Chan
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
| | - Jodhbir S Mehta
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore.,School of Material Science and Engineering, Nanyang Technological University, Singapore, Singapore.,Yong Loo Lin School of Medicine, Department of Ophthalmology, National University of Singapore, Singapore, Singapore
| | - Kelvin Y C Teo
- Singapore National Eye Centre, Singapore, Singapore.,Singapore Eye Research Institute, Singapore, Singapore.,Duke-NUS Graduate Medical School, Ophthalmology and Visual Sciences Academic Clinical Programme, Singapore, Singapore
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23
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Arce-Gonzalez R, Chacon-Camacho OF, Navas-Perez A, Gonzalez-Gonzalez MC, Martinez-Aguilar A, Zenteno JC. Novel CHRDL1 mutation causing X-linked megalocornea in a family with mild anterior segment manifestations in carrier females. Ophthalmic Genet 2021; 43:224-229. [PMID: 34844512 DOI: 10.1080/13816810.2021.2002917] [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: 10/19/2022]
Abstract
PURPOSE X-linked megalocornea (XMC) is a rare anterior segment malformation characterized by a nonprogressive enlargement of the cornea to 13 mm or greater in the setting of normal intraocular pressure. XMC is caused by mutations in the CHRDL1 gene and it is inherited as an X-linked recessive trait affecting only males. Here, we describe the results of phenotypic and genetic assessment in a novel XMC pedigree. METHODS Three subjects (a father and his two daughters) underwent a complete clinical and imaging ocular examination including biomicroscopy, fundoscopy, tonometry, visual acuity, Pentacam Scheimpflug imaging, anterior segment Swept Source OCT, and ultrabiomicroscopy. Genetic analysis was performed through whole exome sequencing in 3 family members. Candidate variants were validated by sanger sequencing. RESULTS The affected father exhibited megalocornea, very deep anterior chambers, retrocorneal pigmentation, iris atrophy, queer iris configuration, extremely open iridocorneal angles, and cataracts. Notably, both daughters showed queer iris configuration and abnormally widely open iridocorneal angles in both eyes. Genetic analysis identified a novel hemizygous c.207+1G>A splicing variant in CHRDL1 in the affected father. Both mildly affected daughters were heterozygous for the pathogenic variant. CONCLUSIONS Here, we report an additional XMC family due to a novel mutation in the CHRDL1 gene. Mild anterior segment anomalies were observed in two heterozygous carriers demonstrating for the first time a CHRDL1-linked phenotype in females. A detailed comparison of the clinical and genetic features of this pedigree with those observed in previously published XMC cases is also presented.
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Affiliation(s)
- Rocio Arce-Gonzalez
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Oscar F Chacon-Camacho
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico.,Carrera de Médico Cirujano, Facultad De Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, Mexico
| | - Alejandro Navas-Perez
- Cornea Department, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | | | - Alan Martinez-Aguilar
- Retinal Dystrophies Clinic, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Juan Carlos Zenteno
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico.,Biochemistry Department, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Mexico City, Mexico
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24
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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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25
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Viggiano E, Politano L. X Chromosome Inactivation in Carriers of Fabry Disease: Review and Meta-Analysis. Int J Mol Sci 2021; 22:ijms22147663. [PMID: 34299283 PMCID: PMC8304911 DOI: 10.3390/ijms22147663] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 12/27/2022] Open
Abstract
Anderson-Fabry disease is an X-linked inborn error of glycosphingolipid catabolism caused by a deficiency of α-galactosidase A. The incidence ranges between 1: 40,000 and 1:117,000 of live male births. In Italy, an estimate of incidence is available only for the north-western Italy, where it is of approximately 1:4000. Clinical symptoms include angiokeratomas, corneal dystrophy, and neurological, cardiac and kidney involvement. The prevalence of symptomatic female carriers is about 70%, and in some cases, they can exhibit a severe phenotype. Previous studies suggest a correlation between skewed X chromosome inactivation and symptoms in carriers of X-linked disease, including Fabry disease. In this review, we briefly summarize the disease, focusing on the clinical symptoms of carriers and analysis of the studies so far published in regards to X chromosome inactivation pattern, and manifesting Fabry carriers. Out of 151 records identified, only five reported the correlation between the analysis of XCI in leukocytes and the related phenotype in Fabry carriers, in particular evaluating the Mainz Severity Score Index or cardiac involvement. The meta-analysis did not show any correlation between MSSI or cardiac involvement and skewed XCI, likely because the analysis of XCI in leukocytes is not useful for predicting the phenotype in Fabry carriers.
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Affiliation(s)
- Emanuela Viggiano
- Department of Prevention, UOC Hygiene Service and Public Health, ASL Roma 2, 00142 Rome, Italy
- Correspondence: (E.V.); (L.P.)
| | - Luisa Politano
- Cardiomyology and Medical Genetics, Department of Experimental Medicine, Luigi Vanvitelli University, 80138 Naples, Italy
- Correspondence: (E.V.); (L.P.)
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26
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Next-Generation Sequencing Applications for Inherited Retinal Diseases. Int J Mol Sci 2021; 22:ijms22115684. [PMID: 34073611 PMCID: PMC8198572 DOI: 10.3390/ijms22115684] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/21/2021] [Accepted: 05/22/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal diseases (IRDs) represent a collection of phenotypically and genetically diverse conditions. IRDs phenotype(s) can be isolated to the eye or can involve multiple tissues. These conditions are associated with diverse forms of inheritance, and variants within the same gene often can be associated with multiple distinct phenotypes. Such aspects of the IRDs highlight the difficulty met when establishing a genetic diagnosis in patients. Here we provide an overview of cutting-edge next-generation sequencing techniques and strategies currently in use to maximise the effectivity of IRD gene screening. These techniques have helped researchers globally to find elusive causes of IRDs, including copy number variants, structural variants, new IRD genes and deep intronic variants, among others. Resolving a genetic diagnosis with thorough testing enables a more accurate diagnosis and more informed prognosis and should also provide information on inheritance patterns which may be of particular interest to patients of a child-bearing age. Given that IRDs are heritable conditions, genetic counselling may be offered to help inform family planning, carrier testing and prenatal screening. Additionally, a verified genetic diagnosis may enable access to appropriate clinical trials or approved medications that may be available for the condition.
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27
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Hadalin V, Šuštar M, Volk M, Maver A, Sajovic J, Jarc-Vidmar M, Peterlin B, Hawlina M, Fakin A. Cone Dystrophy Associated with a Novel Variant in the Terminal Codon of the RPGR- ORF15. Genes (Basel) 2021; 12:genes12040499. [PMID: 33805381 PMCID: PMC8066792 DOI: 10.3390/genes12040499] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 03/23/2021] [Accepted: 03/24/2021] [Indexed: 12/30/2022] Open
Abstract
Mutations in RPGRORF15 are associated with rod-cone or cone/cone-rod dystrophy, the latter associated with mutations at the distal end. We describe the phenotype associated with a novel variant in the terminal codon of the RPGRORF15 c.3457T>A (Ter1153Lysext*38), which results in a C-terminal extension. Three male patients from two families were recruited, aged 31, 35, and 38 years. Genetic testing was performed by whole exome sequencing. Filtered variants were analysed according to the population frequency, ClinVar database, the variant’s putative impact, and predicted pathogenicity; and were classified according to the ACMG guidelines. Examination included visual acuity (Snellen), colour vision (Ishihara), visual field, fundus autofluorescence (FAF), optical coherence tomography (OCT), and electrophysiology. All patients were myopic, and had central scotoma and reduced colour vision. Visual acuities on better eyes were counting fingers, 0.3 and 0.05. Electrophysiology showed severely reduced cone-specific responses and macular dysfunction, while the rod-specific response was normal. FAF showed hyperautofluorescent ring centred at the fovea encompassing an area of photoreceptor loss approximately two optic discs in diameter (3462–6342 μm). Follow up after 2–11 years showed enlargement of the diameter (avg. 100 μm/year). The novel c.3457T>A (Ter1153Lysext*38) mutation in the terminal RPGRORF15 codon is associated with cone dystrophy, which corresponds to the previously described phenotypes associated with mutations in the distal end of the RPGRORF15. Minimal progression during follow-up years suggests a relatively stable disease after the initial loss of the central cones.
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Affiliation(s)
- Vlasta Hadalin
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
| | - Maja Šuštar
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
| | - Marija Volk
- Clinical Institute of Medical Genetics, University Medical Centre Ljubljana, Šlajmerjeva ulica 4, 1000 Ljubljana, Slovenia; (M.V.); (A.M.); (B.P.)
| | - Aleš Maver
- Clinical Institute of Medical Genetics, University Medical Centre Ljubljana, Šlajmerjeva ulica 4, 1000 Ljubljana, Slovenia; (M.V.); (A.M.); (B.P.)
| | - Jana Sajovic
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
| | - Martina Jarc-Vidmar
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
| | - Borut Peterlin
- Clinical Institute of Medical Genetics, University Medical Centre Ljubljana, Šlajmerjeva ulica 4, 1000 Ljubljana, Slovenia; (M.V.); (A.M.); (B.P.)
| | - Marko Hawlina
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
| | - Ana Fakin
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; (V.H.); (M.Š.); (J.S.); (M.J.-V.); (M.H.)
- Correspondence:
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28
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Georgiou M, Ali N, Yang E, Grewal PS, Rotsos T, Pontikos N, Robson AG, Michaelides M. Extending the phenotypic spectrum of PRPF8, PRPH2, RP1 and RPGR, and the genotypic spectrum of early-onset severe retinal dystrophy. Orphanet J Rare Dis 2021; 16:128. [PMID: 33712029 PMCID: PMC7953775 DOI: 10.1186/s13023-021-01759-8] [Citation(s) in RCA: 7] [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: 09/19/2020] [Accepted: 02/25/2021] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To present the detailed retinal phenotype of patients with Leber Congenital Amaurosis/Early-Onset Severe Retinal Dystrophy (LCA/EOSRD) caused by sequence variants in four genes, either not (n = 1) or very rarely (n = 3) previously associated with the disease. METHODS Retrospective case series of LCA/EOSRD from four pedigrees. Chart review of clinical notes, multimodal retinal imaging, electrophysiology, and molecular genetic testing at a single tertiary referral center (Moorfields Eye Hospital, London, UK). RESULTS The mean age of presentation was 3 months of age, with disease onset in the first year of life in all cases. Molecular genetic testing revealed the following disease-causing variants: PRPF8 (heterozygous c.5804G > A), PRPH2 (homozygous c.620_627delinsTA, novel variant), RP1 (homozygous c.4147_4151delGGATT, novel variant) and RPGR (heterozygous c.1894_1897delGACA). PRPF8, PRPH2, and RP1 variants have very rarely been reported, either as unique cases or case reports, with limited clinical data presented. RPGR variants have not previously been associated with LCA/EOSRD. Clinical history and detailed retinal imaging are presented. CONCLUSIONS The reported cases extend the phenotypic spectrum of PRPF8-, PRPH2-, RP1-, and RPGR-associated disease, and the genotypic spectrum of LCA/EOSRD. The study highlights the importance of retinal and functional phenotyping, and the importance of specific genetic diagnosis to potential future therapy.
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Affiliation(s)
- Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, UK
- Moorfields Eye Hospital, London, UK
| | | | | | | | - Tryfon Rotsos
- First Division of Ophthalmology, General Hospital of Athens, National and Kapodistrian University of Athens, Athens, Greece
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, UK
- Moorfields Eye Hospital, London, UK
| | - Anthony G Robson
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, UK
- Moorfields Eye Hospital, London, UK
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, UK.
- Moorfields Eye Hospital, London, UK.
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29
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De Silva SR, Arno G, Robson AG, Fakin A, Pontikos N, Mohamed MD, Bird AC, Moore AT, Michaelides M, Webster AR, Mahroo OA. The X-linked retinopathies: Physiological insights, pathogenic mechanisms, phenotypic features and novel therapies. Prog Retin Eye Res 2020; 82:100898. [PMID: 32860923 DOI: 10.1016/j.preteyeres.2020.100898] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/07/2020] [Accepted: 08/21/2020] [Indexed: 02/08/2023]
Abstract
X-linked retinopathies represent a significant proportion of monogenic retinal disease. They include progressive and stationary conditions, with and without syndromic features. Many are X-linked recessive, but several exhibit a phenotype in female carriers, which can help establish diagnosis and yield insights into disease mechanisms. The presence of affected carriers can misleadingly suggest autosomal dominant inheritance. Some disorders (such as RPGR-associated retinopathy) show diverse phenotypes from variants in the same gene and also highlight limitations of current genetic sequencing methods. X-linked disease frequently arises from loss of function, implying potential for benefit from gene replacement strategies. We review X-inactivation and X-linked inheritance, and explore burden of disease attributable to X-linked genes in our clinically and genetically characterised retinal disease cohort, finding correlation between gene transcript length and numbers of families. We list relevant genes and discuss key clinical features, disease mechanisms, carrier phenotypes and novel experimental therapies. We consider in detail the following: RPGR (associated with retinitis pigmentosa, cone and cone-rod dystrophy), RP2 (retinitis pigmentosa), CHM (choroideremia), RS1 (X-linked retinoschisis), NYX (complete congenital stationary night blindness (CSNB)), CACNA1F (incomplete CSNB), OPN1LW/OPN1MW (blue cone monochromacy, Bornholm eye disease, cone dystrophy), GPR143 (ocular albinism), COL4A5 (Alport syndrome), and NDP (Norrie disease and X-linked familial exudative vitreoretinopathy (FEVR)). We use a recently published transcriptome analysis to explore expression by cell-type and discuss insights from electrophysiology. In the final section, we present an algorithm for genes to consider in diagnosing males with non-syndromic X-linked retinopathy, summarise current experimental therapeutic approaches, and consider questions for future research.
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Affiliation(s)
- Samantha R De Silva
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Gavin Arno
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony G Robson
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Ana Fakin
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Ljubljana University Medical Centre, Ljubljana, Slovenia
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Moin D Mohamed
- Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK
| | - Alan C Bird
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, UCSF School of Medicine, San Francisco, CA, USA
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Andrew R Webster
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Omar A Mahroo
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK; Section of Ophthalmology, King's College London, UK; Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.
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30
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Li HP, Yuan SQ, Wang XG, Sheng XL, Li XR. Myopia with X-linked retinitis pigmentosa results from a novel gross deletion of RPGR gene. Int J Ophthalmol 2020; 13:1306-1311. [PMID: 32821686 DOI: 10.18240/ijo.2020.08.18] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/29/2020] [Indexed: 12/31/2022] Open
Abstract
AIM To identify mutations with whole exome sequencing (WES) in a Chinese X-linked retinitis pigmentosa (XLRP) family. METHODS Patients received the comprehensive ophthalmic evaluation. Genomic DNA was extracted from peripheral blood and subjected to SureSelect Human All Exon 6+ UTR exon capture kit. The exons were sequenced as 100 base paired reads on Illumina HiSeq2500 system. Only mutations that resulted in a change in amino acid sequence were selected. A pattern of inheritance of the RP family was aligned to identified causal mutation. RESULTS We analysed the data of WES information from XLRP family. The analysis revealed a hemizygous large genomic deletion of RPGR c.29_113del was responsible for this XLRP. The gross deletion lead to a frame-shift mutation and generate stop codon at 7 animo acid behind Asp (D10Afs*7), which would serious truncate RPGR protein. The novel frame-shift mutation was found to segregate with retinitis pigmentosa (RP) phenotype in this family. Bilateral myopia was present on the male patients, but carrier female showed unilateral myopia without RP. CONCLUSION Our study identifies a novel frame-shift mutation of RPGR in a Chinese family, which would expand the spectrum of RPGR mutations. The geno-phenotypic analysis reveals a correlation between RP and myopia. Although exact mechanism of RP related myopia is still unknown, but the novel frame-shift mutation will give our hit on studying the molecular pathogenesis of RP and myopia.
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Affiliation(s)
- Hui-Ping Li
- Tianjin Medical University Eye Hospital, Tianjin Key Laboratory of Retinal Functions and Diseases, Eye Institute and School of Optometry, Tianjin 300384, China.,Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, First Affiliated Hospital of Northwest University for Nationalities, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750002, Ningxia Hui Autonomous Region, China
| | - Shi-Qin Yuan
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, First Affiliated Hospital of Northwest University for Nationalities, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750002, Ningxia Hui Autonomous Region, China
| | - Xiao-Guang Wang
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, First Affiliated Hospital of Northwest University for Nationalities, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750002, Ningxia Hui Autonomous Region, China
| | - Xun-Lun Sheng
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, First Affiliated Hospital of Northwest University for Nationalities, Ningxia Clinical Research Center on Diseases of Blindness in Eye, Yinchuan 750002, Ningxia Hui Autonomous Region, China
| | - Xiao-Rong Li
- Tianjin Medical University Eye Hospital, Tianjin Key Laboratory of Retinal Functions and Diseases, Eye Institute and School of Optometry, Tianjin 300384, China
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31
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Parmeggiani F. X-Chromosome Insight for Targeting Gene Therapy. Ophthalmol Retina 2020; 4:521-522. [PMID: 32381254 DOI: 10.1016/j.oret.2020.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 12/31/2019] [Accepted: 01/06/2020] [Indexed: 10/24/2022]
Affiliation(s)
- Francesco Parmeggiani
- Department of Morphology, Experimental Medicine and Surgery, University of Ferrara & Ferrara University Hospital, Ferrara, Italy.
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