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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Lee HW, Lee EK. Asymmetric presentation with a novel RP2 gene mutation in X-Linked retinitis pigmentosa: a case report. BMC Ophthalmol 2023; 23:221. [PMID: 37198560 DOI: 10.1186/s12886-023-02968-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 05/09/2023] [Indexed: 05/19/2023] Open
Abstract
BACKGROUND We present the detailed multimodal imaging analysis in a case of X-linked retinitis pigmentosa (XLRP) exhibiting a markedly asymmetric presentation with a novel RP2 mutation. CASE PRESENTATION A 25-year-old woman complained of decreased vision in the right eye as well as night blindness. Her visual acuity was 20/100 (OD) and 20/20 (OS). Fundus examination revealed bone spicule pigmentation with tessellated changes in the fundus within the posterior pole. Optical coherence tomography (OCT) showed generalized disruption of foveal microstructures in the OD. No abnormal findings were identified, but localized ellipsoid zone band losses were observed on OCT in the OS. Fundus autofluorescence revealed multiple patchy hypo-autofluorescent lesions in the OD and a tapetal-like radial reflex against a dark background in the OS. Fluorescein angiography and OCT angiography revealed diffuse mottled hyperfluorescence with reduced retinal vessel density in the OD and no evidence of vascular compromise in the OS. Goldmann perimetry demonstrated a constricted visual field, and electrophysiological assessment revealed an extinguished rod response and a severely impaired cone response in the OD. Molecular genetic tests via next-generation sequencing revealed the pathogenic variant to be a heterozygous frameshift mutation in RP2 (RP2, p.Glu269Glyfs*7), resulting in premature termination of the protein. CONCLUSIONS Random X-inactivation may be attributed to interocular differences in the severity of XLRP in female carriers. A novel frameshift mutation in the RP2 gene and a comprehensive phenotypic evaluation in the current study may broaden the spectrum of the disease in XLRP carriers.
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Affiliation(s)
- Hyun Woo Lee
- Pre-medical Program, Seoul National University College of Medicine, Seoul, Korea
| | - Eun Kyoung Lee
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Hospital, #101, Daehak-ro, Jongno-gu, Seoul, Republic of Korea.
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3
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Cheloni R, Jackson D, Moosajee M. A Natural History Study of RP2-Related Retinopathy. J Clin Med 2022; 11:jcm11236877. [PMID: 36498452 PMCID: PMC9738434 DOI: 10.3390/jcm11236877] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/10/2022] [Accepted: 11/18/2022] [Indexed: 11/23/2022] Open
Abstract
X-linked retinitis pigmentosa (RP) is a severe form of RP, often with early macular involvement. This study aimed to characterise the natural history of patients with a diagnosis of X-linked RP due to RP2 mutations. Clinical details, best-corrected visual acuity (BCVA) and multimodal retinal imaging were retrospectively collected from patients with RP2 variants from Moorfields Eye Hospital (London, UK). Measures of the ellipsoid-zone (EZ) width, central retinal thickness (CRT), and thickness of the photoreceptor and retinal pigment epithelium complex (PR+RPE, taken between the external limiting membrane and RPE) were extracted from spectral-domain optical coherence tomography (SD-OCT) scans. A total of 47 affected males (median baseline age: 20 years, IQR: 12.5−36.5) were included, and 41 had two or more visits (median follow-up: 8.0 years, IQR: 3.2−14.5). A total of 24 RP2 variants were identified, 13 of which were novel. BCVA dropped from 0.66 LogMAR at baseline (IQR, 0.35−1.4) to 1.3 LogMAR at the most recent visit (IQR: 0.6−1.4). SD-OCT revealed a prevalent outer retinal atrophy (n = 23/35, 65.7%), and measurable EZ width at baseline in 34.3% of patients (n = 12). Age significantly affected all quantitative measures (p < 0.001) except EZ width (p = 0.58), with exponential decays of 46−49% and 12.6−33.9% per decade for BCVA and SD-OCT measures, respectively. RP2 patients exhibited rapid progression to outer retina atrophy and early macular involvement with substantial vision loss by age 30−40.
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Affiliation(s)
- Riccardo Cheloni
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - Daniel Jackson
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
- The Francis Crick Institute, London NW1 1AT, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
- Correspondence:
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Chivers M, Li N, Pan F, Wieffer H, Slowik R, Leartsakulpanitch J. The Burden of X-Linked Retinitis Pigmentosa on Patients and Society: A Narrative Literature Review. Clinicoecon Outcomes Res 2021; 13:565-572. [PMID: 34188501 PMCID: PMC8236258 DOI: 10.2147/ceor.s297287] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/10/2021] [Indexed: 01/18/2023] Open
Abstract
X-linked retinitis pigmentosa (XLRP) is a severe form of retinitis pigmentosa (RP), a rare, inherited retinal degenerative disorder, that causes blindness. The aim of this literature review was to identify what is currently known about the burden of XLRP. Literature databases were searched for articles describing the clinical, humanistic, or economic burden of XLRP or RP in the US, Japan, France, Germany, Italy, Spain, and the UK, published in English between 2014 and 2019; gray literature and cited references were reviewed. Literature describing XLRP is limited as this is an ultra-rare condition; findings relating to burden of RP have been reported with interpretation of how burden differs for XLRP. In XLRP, night blindness usually presents in the first decade of life, followed by loss of peripheral and then central vision; legal blindness is reported at a median of 45 years in affected males (vs median 70 years for RP). There is limited evidence of humanistic or economic burden specific to XLRP; one study identified greater vision-related activity limitations in patients with XLRP compared with the wider RP population. Qualitative studies describe increased humanistic burden for people living with RP; difficulty undertaking everyday tasks (driving, hobbies, reading), psychosocial burden and barriers to work and career. People described the emotional impact of dealing with progression of RP, ongoing social and physical challenges, and the impact of RP on relationships. The economic burden of RP is associated with lost productivity, greater healthcare costs and increasing requirement for formal and informal care. In summary, XLRP remains an untreatable condition that can impact people from childhood. The humanistic burden of RP has been shown to increase as the disease progresses; hence, in XLRP the earlier onset and earlier progression to blindness during prime working years may mean a comparatively greater lifetime burden of disease.
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Affiliation(s)
| | - Nan Li
- Janssen Global Services,LLC, Raritan, NJ, 08869, USA
| | - Feng Pan
- Janssen Global Services,LLC, Raritan, NJ, 08869, USA
| | | | - Rafal Slowik
- Janssen Global Services,LLC, Raritan, NJ, 08869, USA
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Ortiz-Ramirez GY, Villanueva-Mendoza C, Zenteno Ruiz JC, Reyes M, Cortés-González V. Autofluorescence in female carriers with choroideremia: A familial case with a novel mutation in the CHM gene. Ophthalmic Genet 2020; 41:625-628. [PMID: 32835561 DOI: 10.1080/13816810.2020.1810283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Choroideremia is an X-linked chorioretinal dystrophy caused by mutations in the CHM gene. The main differential diagnosis is X-linked retinitis pigmentosa. Clinically, male patients that are affected by these two diseases have similar symptoms. This work aims to report a familial case of choroideremia initially diagnosed as X-linked retinitis pigmentosa with a novel mutation in the CHM gene, and the relevance of fundus autofluorescence (FAF) in female carriers. MATERIALS AND METHODS A complete ophthalmological evaluation was done in a 37-year-old woman and her 53-year-old maternal uncle; the uncle had been diagnosed previously with X-linked retinitis pigmentosa. A visual field test, FAF imaging, full-field electroretinography, and a genetic test were performed. RESULTS In the proband, the fundoscopy revealed diffuse changes in the retinal pigment epithelium in both eyes, and the FAF showed a speckled pattern of low- and high-density. The maternal uncle's ophthalmological evaluation showed choroidal and retinal atrophy consistent with choroideremia. The molecular analysis revealed a pathogenic variant in the CHM gene, c.190-1 G > T. CONCLUSIONS In female carriers of choroideremia and X-linked retinitis pigmentosa, differential diagnosis may be challenging. A speckled pattern of low- and high-density in autofluorescence is commonly found in female carriers of choroideremia. FAF is a powerful tool for making a correct clinical diagnosis because the pattern in FAF is much more apparent than the visible retinal changes obtained by fundoscopy. Although it is crucial to perform molecular analysis to confirm the diagnosis, FAF is useful when genetic testing may not be readily available.
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Affiliation(s)
- Grecia Yael Ortiz-Ramirez
- Ophthalmology, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
| | | | - Juan Carlos Zenteno Ruiz
- Research Unit and Genetics, Institute of Ophthalmology "Conde de Valenciana" Foundation, Mexico City, Mexico.,Department of Biochemistry, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mariana Reyes
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
| | - Vianney Cortés-González
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
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7
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Giacalone JC, Andorf JL, Zhang Q, Burnight ER, Ochoa D, Reutzel AJ, Collins MM, Sheffield VC, Mullins RF, Han IC, Stone EM, Tucker BA. Development of a Molecularly Stable Gene Therapy Vector for the Treatment of RPGR-Associated X-Linked Retinitis Pigmentosa. Hum Gene Ther 2020; 30:967-974. [PMID: 31106594 DOI: 10.1089/hum.2018.244] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In a screen of 1,000 consecutively ascertained families, we recently found that mutations in the gene RPGR are the third most common cause of all inherited retinal disease. As the two most frequent disease-causing genes, ABCA4 and USH2A, are far too large to fit into clinically relevant adeno-associated virus (AAV) vectors, RPGR is an obvious early target for AAV-based ocular gene therapy. In generating plasmids for this application, we discovered that those containing wild-type RPGR sequence, which includes the highly repetitive low complexity region ORF15, were extremely unstable (i.e., they showed consistent accumulation of genomic changes during plasmid propagation). To develop a stable RPGR gene transfer vector, we used a bioinformatics approach to identify predicted regions of genomic instability within ORF15 (i.e., potential non-B DNA conformations). Synonymous substitutions were made in these regions to reduce the repetitiveness and increase the molecular stability while leaving the encoded amino acid sequence unchanged. The resulting construct was subsequently packaged into AAV serotype 5, and the ability to drive transcript expression and functional protein production was demonstrated via subretinal injection in rat and pull-down assays, respectively. By making synonymous substitutions within the repetitive region of RPGR, we were able to stabilize the plasmid and subsequently generate a clinical-grade gene transfer vector (IA-RPGR). Following subretinal injection in rat, we demonstrated that the augmented transcript was expressed at levels similar to wild-type constructs. By performing in vitro pull-down experiments, we were able to show that IA-RPGR protein product retained normal protein binding properties (i.e., analysis revealed normal binding to PDE6D, INPP5E, and RPGRIP1L). In summary, we have generated a stable RPGR gene transfer vector capable of producing functional RPGR protein, which will facilitate safety and toxicity studies required for progression to an Investigational New Drug application.
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Affiliation(s)
- Joseph C Giacalone
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Jeaneen L Andorf
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Qihong Zhang
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Erin R Burnight
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Dalyz Ochoa
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Austin J Reutzel
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Malia M Collins
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Val C Sheffield
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Robert F Mullins
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Ian C Han
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Edwin M Stone
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Budd A Tucker
- Department of Ophthalmology and Visual Sciences, Institute for Vision Research, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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8
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Zhang Z, Dai H, Wang L, Tao T, Xu J, Sun X, Yang L, Li G. Novel mutations of RPGR in Chinese families with X-linked retinitis pigmentosa. BMC Ophthalmol 2019; 19:240. [PMID: 31775781 PMCID: PMC6882249 DOI: 10.1186/s12886-019-1250-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 11/18/2019] [Indexed: 12/15/2022] Open
Abstract
Background RP (retinitis pigmentosa) is a group of hereditary retinal degenerative diseases. XLRP is a relatively severe subtype of RP. Thus, it is necessary to identify genes and mutations in patients who present with X-linked retinitis pigmentosa. Methods Genomic DNA was extracted from peripheral blood. The coding regions and intron-exon boundaries of the retinitis pigmentosa GTPase regulator (RPGR) and RP2 genes were amplified by PCR and then sequenced directly. Ophthalmic examinations were performed to identify affected individuals from two families and to characterize the phenotype of the disease. Results Mutation screening demonstrated two novel nonsense mutations (c.1541C > G; p.S514X and c.2833G > T; p.E945X) in the RPGR gene. The clinical manifestation of family 1 with mutations in exon 13 was mild. Genotype-phenotype correlation analysis suggested that patients with mutations close to the downstream region of ORF15 in family 2 manifested an early loss of cone function. Family 2 carried a nonsense mutation in ORF15 that appeared to have a semi-dominant pattern of inheritance. All male patients and two female carriers in family 2 manifested pathological myopia (PM), indicating that there may be a distinctive X-linked genotype-phenotype correlation between RP and PM. Conclusions We identified two novel mutations of the RPGR gene, which broadens the spectrum of RPGR mutations and the phenotypic spectrum of the disease in Chinese families.
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Affiliation(s)
- Zhimeng Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Hehua Dai
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Lei Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Tianchang Tao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Jing Xu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Xiaowei Sun
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China
| | - Liping Yang
- Department of Ophthalmology, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Peking University Third Hospital, Beijing, People's Republic of China
| | - Genlin Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Lab, Beijing, People's Republic of China.
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9
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Abstract
This article summarizes the recent advances in our understanding of a major retinal disease gene RPGR (retinitis pigmentosa GTPase regulator), mutations in which are associated with majority of X-linked forms of retinal degenerations. A great deal of work has been done to uncover the ciliary localization of RPGR and its interacting proteins in the retina. However, the molecular mechanisms of action of RPGR in the photoreceptors are still unclear. Recent studies have begun to shed light on the intracellular pathways in which RPGR is likely involved. The deregulation of such pathways may underlie the pathogenesis of severe retinal degeneration associated with RPGR. With the recent advances in the gene augmentation therapy for RPGR-associated disease, there is a lot of excitement in the field. Patients with RPGR mutations, however, present with clinically heterogeneous manifestations. It is therefore imperative to examine the function of RPGR in detail, so that we can design patient-oriented therapeutic strategies for this disease.
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Affiliation(s)
- Hemant Khanna
- Department of Ophthalmology and Neurobiology, UMASS Medical School, Worcester, MA, USA.
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10
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Huang X, Liu Y, Yu X, Huang Q, Lin C, Zeng J, Lan F, Wang Z. The clinical application of preimplantation genetic diagnosis for X-linked retinitis pigmentosa. J Assist Reprod Genet 2019; 36:989-994. [PMID: 30887160 DOI: 10.1007/s10815-019-01434-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 03/04/2019] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To investigate the usefulness of preimplantation genetic diagnosis (PGD) based on mutated allele revealed by sequencing with aneuploidy and linkage analyses (MARSALA) for a pedigree with X-linked retinitis pigmentosa (XLRP). METHODS One pathogenic mutation (c.494G > A) of the retinitis pigmentosa GTPase regulator (RPGR) gene was identified in a pedigree affected by XLRP. Then, PGD was carried out for the couple, of which the wife was an XLRP carrier. Three blastocysts were biopsied and then MARSALA was performed by next-generation sequencing (NGS). Prenatal diagnosis was also carried out to confirm the PGD results. RESULTS Three blastocysts were all unaffected. Then, one of the embryos was chosen randomly to be transferred, and the pregnancy was acquired successfully. The results of prenatal diagnosis were consistent with the PGD results. The fetus did not carry RPGR mutation (c.494G > A) and had normal chromosome karyotype. As a result, a healthy baby free of XLRP condition was born. CONCLUSION The PGD method based on MARSALA was established and applied to a family with XLRP successfully. MARSALA will be a valid tool, not only for XLRP families but also for families affected with other monogenetic disorders, to prevent transmission of the genetic disease from parents to offspring.
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Affiliation(s)
- Xinghua Huang
- Research Center for Molecular Diagnosis of Genetic Diseases, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, 156 Xi'erhuanbei Road, Fuzhou City, 350025, Fujian Province, People's Republic of China
| | - Yun Liu
- Department of Obstetrics & Gynecology, Center of Reproductive Medicine, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, Fuzhou, 350025, Fujian, China
| | - Xiurong Yu
- Research Center for Molecular Diagnosis of Genetic Diseases, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, 156 Xi'erhuanbei Road, Fuzhou City, 350025, Fujian Province, People's Republic of China
| | - Qiuxiang Huang
- Department of Obstetrics & Gynecology, Center of Reproductive Medicine, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, Fuzhou, 350025, Fujian, China
| | - Chunli Lin
- Department of Obstetrics & Gynecology, Center of Reproductive Medicine, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, Fuzhou, 350025, Fujian, China
| | - Jian Zeng
- Research Center for Molecular Diagnosis of Genetic Diseases, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, 156 Xi'erhuanbei Road, Fuzhou City, 350025, Fujian Province, People's Republic of China
| | - Fenghua Lan
- Research Center for Molecular Diagnosis of Genetic Diseases, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, 156 Xi'erhuanbei Road, Fuzhou City, 350025, Fujian Province, People's Republic of China
| | - Zhihong Wang
- Research Center for Molecular Diagnosis of Genetic Diseases, Fuzhou General Hospital, Clinical College of Fujian Medical University/Dongfang Hospital, Xiamen University Medical College, 156 Xi'erhuanbei Road, Fuzhou City, 350025, Fujian Province, People's Republic of China.
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11
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Nanda A, Salvetti AP, Clouston P, Downes SM, MacLaren RE. Exploring the Variable Phenotypes of RPGR Carrier Females in Assessing their Potential for Retinal Gene Therapy. Genes (Basel) 2018; 9:E643. [PMID: 30567410 DOI: 10.3390/genes9120643] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 11/27/2018] [Accepted: 12/13/2018] [Indexed: 11/16/2022] Open
Abstract
Inherited retinal degenerations are the leading cause of blindness in the working population. X-linked retinitis pigmentosa (XLRP), caused by mutations in the Retinitis pigmentosa GTPase regulator (RPGR) gene is one of the more severe forms, and female carriers of RPGR mutations have a variable presentation. A retrospective review of twenty-three female RPGR carriers aged between 8 and 76 years old was carried out using fundoscopy, autofluorescence imaging (AF), blue reflectance (BR) imaging and optical coherence tomography (OCT). Confirmation of the genetic mutation was obtained from male relatives or Sanger genetic sequencing. Fundus examination and AF demonstrate phenotypic variability in RPGR carriers. The genetic mutation appears indeterminate of the degree of change. We found four distinct classifications based on AF images to describe RPGR carriers; normal (N) representing normal or near-normal AF appearance (n = 1, 4%); radial (R) pattern reflex without pigmentary retinopathy (n = 14, 61%); focal (F) pigmentary retinopathy (n = 5, 22%) and; male (M) phenotype (n = 3, 13%). The phenotypes were precisely correlated in both eyes (rs = 1.0, p < 0.0001). Skewed X-inactivation can result in severely affected carrier females—in some cases indistinguishable from the male pattern and these patients should be considered for RPGR gene therapy. In the cases of the male (M) phenotype where the X-inactivation was skewed, the pattern was similar in both eyes, suggesting that the mechanism is not truly random but may have an underlying genetic basis.
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12
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Nanda A, Salvetti AP, Martinez-Fernandez de la Camara C, MacLaren RE. Misdiagnosis of X-linked retinitis pigmentosa in a choroideremia patient with heavily pigmented fundi. Ophthalmic Genet 2018; 39:380-383. [PMID: 29377744 DOI: 10.1080/13816810.2018.1430242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Inherited retinal diseases are thought to be the leading cause of sight loss in the working age population. Mutations found in the RPGR and CHM genes cause retinitis pigmentosa (RP) and choroideremia, respectively. In the first instance, an X-linked family history of visual field loss commonly raises the suspicion of one of these two genes. In choroideremia, the classic description of a white fundal reflex secondary to the widespread chorioretinal degeneration was made over a hundred years ago in Caucasians. But, it is not so obvious in heavily pigmented fundi. Hence, the clinical diagnosis of CHM in non-Caucasian patients may be challenging in the first stages of the disease. Here we report a case of a Southeast Asian gentleman who has a family history of X-linked retinal degeneration and was found to have a confirmed in-frame deletion of 12 DNA nucleotides in exon 15 of the RPGR gene. Later in life, however, his fundal appearance showed unusual areas of circular pigment hypertrophy and clumping. He was therefore tested for carrying a disease-causing mutation in the CHM gene and a null mutation was found. Since gene therapy trials are ongoing for both of these conditions, it has now become critically important to establish the correct genetic diagnosis in order to recruit suitable candidates. Moreover, this case demonstrates the necessity to remain vigilant in the interpretation of genetic results which are inconsistent with clinical features.
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Affiliation(s)
- A Nanda
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom
| | - A P Salvetti
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom.,b Eye 5 Clinic, Sacco Hospital, University of Milan , Milano , Italy
| | | | - R E MacLaren
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom.,c Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , University of Oxford , Oxford , United Kingdom
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13
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Daiger SP, Bowne SJ, Sullivan LS, Branham K, Wheaton DK, Jones KD, Avery CE, Cadena ED, Heckenlively JR, Birch DG. Molecular Findings in Families with an Initial Diagnose of Autosomal Dominant Retinitis Pigmentosa (adRP). Adv Exp Med Biol 2018; 1074:237-245. [PMID: 29721949 DOI: 10.1007/978-3-319-75402-4_29] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Genetic testing of probands in families with an initial diagnosis of autosomal dominant retinitis pigmentosa (adRP) usually confirms the diagnosis, but there are exceptions. We report results of genetic testing in a large cohort of adRP families with an emphasis on exceptional cases including X-linked RP with affected females; homozygous affected individuals in families with heterozygous, dominant disease; and independently segregating mutations in the same family. Genetic testing was conducted in more than 700 families with a provisional or probable diagnosis of adRP. Exceptions to the proposed mode of inheritance were extracted from our comprehensive patient and family database. In a subset of 300 well-characterized families with a probable diagnosis of adRP, 195 (70%) have dominant mutations in known adRP genes but 25 (8%) have X-linked mutations, 3 (1%) have multiple segregating mutations, and 3 (1%) have dominant-acting mutations in genes previously associated with recessive disease. It is currently possible to determine the underlying disease-causing gene and mutation in approximately 80% of families with an initial diagnosis of adRP, but 10% of "adRP" families have a variant mode of inheritance. Informed genetic diagnosis requires close collaboration between clinicians, genetic counselors, and laboratory scientists.
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Affiliation(s)
- Stephen P Daiger
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center (UTHealth), Houston, TX, USA. .,Ruiz Department of Ophthalmology and Visual Science, UTHealth, Houston, TX, USA.
| | - Sara J Bowne
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | - Lori S Sullivan
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | - Kari Branham
- Kellogg Eye Center, University of Michigan, Ann Arbor, MI, USA
| | | | | | - Cheryl E Avery
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | - Elizabeth D Cadena
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center (UTHealth), Houston, TX, USA
| | | | - David G Birch
- The Retina Foundation of the Southwest, Dallas, TX, USA
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14
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Zhou Q, Yao F, Wang F, Li H, Chen R, Sui R. A heterozygous mutation in RPGR associated with X-linked retinitis pigmentosa in a patient with Turner syndrome mosaicism (45,X/46,XX). Am J Med Genet A 2017; 176:214-218. [PMID: 29135076 DOI: 10.1002/ajmg.a.38501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 07/17/2017] [Accepted: 09/24/2017] [Indexed: 01/15/2023]
Abstract
Turner syndrome with retinitis pigmentosa (RP) is rare, with only three cases reported based on clinical examination alone. We summarized the 4-year follow-up and molecular findings in a 28-year-old patient with Turner syndrome and the typical features of short stature and neck webbing, who also had X-linked RP. Her main complaints were night blindness and progressive loss of vision since the age of 9 years. Ophthalmologic examination, optical coherent tomographic imaging, and visual electrophysiology tests showed classic manifestations of RP. The karyotype of peripheral blood showed mosaicism (45,X [72%]/46,XX[28%]). A novel heterozygous frameshift mutation (c.2403_2406delAGAG, p.T801fsX812) in the RP GTPase regulator (RPGR) gene was detected using next generation sequencing and validated by Sanger sequencing. We believe that this is the first report of X-linked RP in a patient with Turner syndrome associated with mosaicism, and an RPGR heterozygous mutation. We hypothesize that X-linked RP in this woman is not related to Turner syndrome, but may be a manifestation of the lack of a normal paternal X chromosome with intact but mutated RPGR.
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Affiliation(s)
- Qi Zhou
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Fengxia Yao
- Laboratory of Clinical Genetics, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Feng Wang
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas
| | - Hui Li
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Rui Chen
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
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15
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Beltran WA, Cideciyan AV, Boye SE, Ye GJ, Iwabe S, Dufour VL, Marinho LF, Swider M, Kosyk MS, Sha J, Boye SL, Peterson JJ, Witherspoon CD, Alexander JJ, Ying GS, Shearman MS, Chulay JD, Hauswirth WW, Gamlin PD, Jacobson SG, Aguirre GD. Optimization of Retinal Gene Therapy for X-Linked Retinitis Pigmentosa Due to RPGR Mutations. Mol Ther 2017; 25:1866-1880. [PMID: 28566226 DOI: 10.1016/j.ymthe.2017.05.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/14/2017] [Accepted: 05/05/2017] [Indexed: 01/09/2023] Open
Abstract
X-linked retinitis pigmentosa (XLRP) caused by mutations in the RPGR gene is an early onset and severe cause of blindness. Successful proof-of-concept studies in a canine model have recently shown that development of a corrective gene therapy for RPGR-XLRP may now be an attainable goal. In preparation for a future clinical trial, we have here optimized the therapeutic AAV vector construct by showing that GRK1 (rather than IRBP) is a more efficient promoter for targeting gene expression to both rods and cones in non-human primates. Two transgenes were used in RPGR mutant (XLPRA2) dogs under the control of the GRK1 promoter. First was the previously developed stabilized human RPGR (hRPGRstb). Second was a new full-length stabilized and codon-optimized human RPGR (hRPGRco). Long-term (>2 years) studies with an AAV2/5 vector carrying hRPGRstb under control of the GRK1 promoter showed rescue of rods and cones from degeneration and retention of vision. Shorter term (3 months) studies demonstrated comparable preservation of photoreceptors in canine eyes treated with an AAV2/5 vector carrying either transgene under the control of the GRK1 promoter. These results provide the critical molecular components (GRK1 promoter, hRPGRco transgene) to now construct a therapeutic viral vector optimized for RPGR-XLRP patients.
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Affiliation(s)
- William A Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19014, USA.
| | - Artur V Cideciyan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Shannon E Boye
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Guo-Jie Ye
- Applied Genetic Technologies Corporation, Alachua, FL 32615, USA
| | - Simone Iwabe
- Division of Experimental Retinal Therapies, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Valerie L Dufour
- Division of Experimental Retinal Therapies, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Luis Felipe Marinho
- Division of Experimental Retinal Therapies, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Malgorzata Swider
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mychajlo S Kosyk
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jin Sha
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sanford L Boye
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - James J Peterson
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - C Douglas Witherspoon
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - John J Alexander
- Department of Human Genetics, School of Medicine, Emory University, Atlanta, GA 30303, USA
| | - Gui-Shuang Ying
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mark S Shearman
- Applied Genetic Technologies Corporation, Alachua, FL 32615, USA
| | - Jeffrey D Chulay
- Applied Genetic Technologies Corporation, Alachua, FL 32615, USA
| | - William W Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Paul D Gamlin
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Samuel G Jacobson
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gustavo D Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19014, USA
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16
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Abstract
The expression of X-linked genes is equalized between males and females in mammalian species through X-Chromosome inactivation (XCI). Every cell in a female mammalian embryo randomly chooses one X Chromosome for epigenetic silencing at the 8-16 cell stage, resulting in a Gaussian distribution of XCI ratios with a peak at 50:50. At the tail extremes of this distribution, X-linked recessive mutations can manifest in disease in female carriers if the mutant allele is disproportionately active. The role of XCI skewing, if any, in X-linked retinal disease is still unknown, although many have speculated that such skewing accounts for phenotypic variation in female carriers of X-linked retinitis pigmentosa (XlRP). Some investigators have used clinical findings such as tapetal-like reflex, pigmentary changes, and multifocal ERG parameters to approximate XCI patches in the retina. These studies are limited by small cohorts and the relative inaccessibility of retinal tissue for genetic and epigenetic analysis. Although blood has been used as a proxy for other tissues in determining XCI ratios, blood XCI skews with age out of proportion to other tissues and may not accurately reflect retinal XCI ratios. Future investigations in determining retinal XCI ratios and the contribution of XCI to phenotype could potentially impact prognosis for female carriers of X-linked retinal disease.
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Affiliation(s)
- Abigail T Fahim
- Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, 1000 Wall Street, 48105, Ann Arbor, MI, USA.
| | - Stephen P Daiger
- School of Public Health, University of Texas Health Science Center, 1200 Herman Pressler Drive, RAS W-522, 77030, Houston, TX, USA.
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17
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Ogino K, Oishi M, Oishi A, Morooka S, Sugahara M, Gotoh N, Kurimoto M, Yoshimura N. Radial fundus autofluorescence in the periphery in patients with X-linked retinitis pigmentosa. Clin Ophthalmol 2015; 9:1467-74. [PMID: 26316687 PMCID: PMC4544811 DOI: 10.2147/opth.s89371] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose To describe the peripheral autofluorescence images and clinical features of patients with retinal dystrophy who showed radial fundus autofluorescence (FAF) at the posterior pole. Methods The authors retrospectively reviewed pooled wide-field FAF images of 711 patients with retinal dystrophy and 56 family members. Results Eleven eyes of seven women exhibited radial FAF at the posterior pole. Wide-field FAF showed extension of the radial pattern to the periphery in all eyes except one. One woman showed radial hyper-FAF only in the periphery, not at the posterior pole. These eight individuals were X-linked retinitis pigmentosa patients or carriers. The tapetal-like reflex was not observed in their color fundus photographs. The peripheral visual field showed wedge-shaped restriction in some individuals. Conclusion Wide-field FAF imaging can depict radial FAF not only at the posterior pole but also in the periphery in X-linked retinitis pigmentosa carriers. The authors therefore agree with previous reports that radial FAF may be a hallmark of X-linked retinitis pigmentosa.
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Affiliation(s)
- Ken Ogino
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Maho Oishi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akio Oishi
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Satoshi Morooka
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masako Sugahara
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Norimoto Gotoh
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan ; Center for Genomic Medicine, Kyoto University, Kyoto, Japan
| | | | - Nagahisa Yoshimura
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
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18
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Shifera AS, Kay CN. Early-Onset X-Linked Retinitis Pigmentosa in a Heterozygous Female Harboring an Intronic Donor Splice Site Mutation in the Retinitis Pigmentosa GTPase Regulator Gene. Ophthalmic Genet 2014; 36:251-6. [PMID: 24428633 DOI: 10.3109/13816810.2013.879597] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To report a heterozygous female presenting with an early-onset and severe form of X-linked retinitis pigmentosa (XLRP). PATIENTS AND METHODS This is a case series presenting the clinical findings in a heterozygous female with XLRP and two of her family members. Fundus photography, fundus autofluorescence, ocular coherence tomography, and visual perimetry are presented. RESULTS The proband reported here is a heterozygous female who presented at the age of 8 years with an early onset and aggressive form of XLRP. The patient belongs to a four-generation family with a total of three affected females and four affected males. The patient was initially diagnosed with retinitis pigmentosa (RP) at the age of 4 years. Genetic testing identified a heterozygous donor splice site mutation in intron 1 (IVS1 + 1G > A) of the retinitis pigmentosa GTPase regulator gene. The father of the proband was diagnosed with RP when he was a young child. The sister of the proband, evaluated at the age of 6 years, showed macular pigmentary changes. CONCLUSIONS Although carriers of XLRP are usually asymptomatic or have a mild disease of late onset, the proband presented here exhibited an early-onset, aggressive form of the disease. It is not clear why some carrier females manifest a severe phenotype. A better understanding of the genetic processes involved in the penetrance and expressivity of XLRP in heterozygous females could assist in providing the appropriate counseling to affected families.
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Acton JH, Greenberg JP, Greenstein VC, Marsiglia M, Tabacaru M, Theodore Smith R, Tsang SH. Evaluation of multimodal imaging in carriers of X-linked retinitis pigmentosa. Exp Eye Res 2013; 113:41-8. [PMID: 23669302 DOI: 10.1016/j.exer.2013.05.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 04/26/2013] [Accepted: 05/01/2013] [Indexed: 11/23/2022]
Abstract
The aim of this study was to investigate visualization of the tapetal-like reflex using current imaging modalities and evaluate SD-OCT changes in known carriers of X-linked retinitis pigmentosa (XLRP); the objective being the development of an optimal protocol for clinicians to identify carriers. Ten XLRP carriers (19 eyes) were examined using color fundus photography, 488 nm reflectance (488-R), near-infrared reflectance (NIR-R), autofluorescence (AF) and spectral domain optical coherence tomography (SD-OCT) imaging (Spectralis SLO-OCT, Heidelberg). Horizontal line scans through the fovea were acquired in all subjects and in a group of 10 age-similar controls. Peripheral SD-OCT scans (extending to 27.5° eccentricity) were also acquired in both eyes of 7 carriers. MP-1 microperimetery (10-2 pattern; Nidek) was performed in one eye of each carrier. For the XLRP carriers, a tapetal reflex was observed with all imaging modalities in 8 of 19 eyes. It had the same retinal location on color fundus, 488-R and NIR-R imaging but a different location on AF. The tapetal reflex was most easily detected in 488-R images. The horizontal foveal SD-OCT scans were qualitatively normal, but measurements showed significant outer retinal layer thinning in all eyes. Additionally, the 14 eyes with peripheral SD-OCTs demonstrated patchy loss of the inner segment ellipsoid band. Microperimetry exhibited patchy visual sensitivity loss in 9 eyes. Full field ERGs were variable, ranging from normal to severely abnormal rod and cone responses. Our findings suggest that an optimal protocol for identifying carriers of XLRP should include 488-R imaging in a multimodal approach. Peripheral SD-OCT imaging and central retinal layer quantification revealed significant structural abnormalities.
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