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PURPOSE: Evaluating the presence of class 3, 4, and 5 genetic variants in inherited retinal disease (IRD) genes in patients with retinopathy of unknown origin (RUO). METHODS: Multicentric retrospective study of RUO cases diagnosed between January 2012 and February 2022. General and ophthalmologic history, complete ophthalmologic examination, antiretinal antibodies, and IRD gene panel results were analyzed in every patient. Four RUO categories were defined: nonparaneoplastic autoimmune retinopathy, unilateral pigmentary retinopathy, asymmetrical pigmentary retinopathy, and acute zonal occult outer retinopathy. RESULTS: The authors included 12 patients (9 females) across these four RUO categories. Mean age at inclusion was 45.6 years (20-68 years). Seven patients demonstrated class 3 variants in IRD genes. Of these, two also demonstrated class 5 variants in other IRD genes. The remaining five patients had negative panel results. IRD gene panel analysis allowed diagnosis refinement in 1 (8.3%) nonparaneoplastic autoimmune retinopathy patient in the RUO cohort. When considering the nonparaneoplastic autoimmune retinopathy subpopulation only, a higher diagnostic yield of 20% (1/5 patients) was achieved. CONCLUSION: Every suspected nonparaneoplastic autoimmune retinopathy patient should benefit from gene panel testing to not overlook undiagnosed IRDs. By contrast, unilateral pigmentary retinopathy, asymmetrical pigmentary retinopathy, and acute zonal occult outer retinopathy subpopulations did not benefit from genetic testing in this study.
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Enfermedades de la Retina , Humanos , Femenino , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Adulto , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Anciano , Adulto Joven , Pruebas Genéticas/métodos , Mutación , Proteínas del Ojo/genéticaRESUMEN
BACKGROUND: Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation is a rare autosomal dominant disease caused by mutations in KIF11 which disrupt EG5 protein function, impacting the development and maintenance of retinal and lymphatic structures due to its expression in the retinal photoreceptor cilia. The primary ocular finding in MCLMR is chorioretinopathy. Additional features can include microphthalmia, angle-closure glaucoma, persistent hyperplastic primary vitreous, cataract, pseudo-coloboma, persistent hyaloid artery, and myopic or hypermetropic astigmatism. The appearance of the chorioretinal lesions as white to pinkish, round, non-elevated atrophic areas devoid of blood vessels resembles the lacunae in Aicardy syndrome. Due to the lack of systematic description of the lesions and significant phenotypical variability, there is an impending need for a detailed report of each case. CASE PRESENTATION: A child with microcephaly detected in the third trimester of gestation began her following in the ophthalmology department due to a non-visually significant cataract. Shortly after, she developed nystagmus and large-angle alternating esotropia with cross-fixation. Her fundus initially showed a pallid optic disc and pigmentary changes, developing thereafter retinal lacunae and a retinal fold. Her differential diagnosis accompanied the dynamic changes in her fundus, which included congenital infections, Leber´s Congenital Amaurosis and Aicardy syndrome. At 19 months old, genetic testing identified a heterozygous mutation (c.1159 C > T, p.Arg387*) in the KIF11 gene. The patient underwent bilateral medial rectus muscle recession surgery at 2 years old for persistent esotropia, with significant improvement. Refraction revealed a hyperopic astigmatism in both eyes (+ 0.25 -2.50 × 180 OD and + 0.75 -2.00 × 170 OS). She continues to require right eye patching for 2 hours daily. CONCLUSIONS: This case report expands the phenotypic spectrum of MCLMR by demonstrating a unique combination of retinal features which sheds new light on differential diagnosis from Aicardy syndrome. Our findings emphasize the significant phenotypic variability associated with MCLMR, particularly regarding ocular involvement. This underscores the importance of detailed clinical evaluation and comprehensive reporting of cases to improve our understanding of the disease spectrum and genotype-phenotype correlations.
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Discapacidad Intelectual , Linfedema , Microcefalia , Humanos , Microcefalia/genética , Microcefalia/diagnóstico , Femenino , Linfedema/genética , Linfedema/diagnóstico , Discapacidad Intelectual/genética , Discapacidad Intelectual/diagnóstico , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Displasia Retiniana , Cinesinas , FaciesRESUMEN
Patient-specific induced pluripotent stem cell-derived (iPSC-derived) cell lines allow for therapies to be tailored to individual patients, increasing therapeutic precision and efficiency. Bietti crystalline dystrophy (BCD) is a rare blinding disease estimated to affect about 67,000 individuals worldwide. Here, we used iPSC-derived retinal pigment epithelium (iRPE) cells from patients with BCD to evaluate adeno-associated virus-mediated (AAV-mediated) gene augmentation therapy strategies. We found that BCD iRPE cells were vulnerable to blue light-induced oxidative stress and that cellular phenotype can be quantified using 3 robust biomarkers: reactive oxygen species (ROS), 4-hydroxy 2-nonenal (4-HNE) levels, and cell death rate. Additionally, we demonstrated that AAV-mediated gene therapy can significantly reduce light-induced cell death in BCD iRPE cells. This is the first proof-of-concept study to our knowledge to show that AAV-CYP4V2 gene therapy can be used to treat light-induced RPE damage in BCD. Furthermore, we observed significant variability in cellular phenotypes among iRPE from patients with BCD of divergent mutations, which outlined genotype-phenotype correlations in BCD patient-specific cell disease models. Our results reveal that patient-specific iRPE cells retained personalized responses to AAV-mediated gene therapy. Therefore, this approach can advance BCD therapy and set a precedent for precision medicine in other diseases, emphasizing the necessity for personalization in healthcare to accommodate individual diversity.
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Distrofias Hereditarias de la Córnea , Dependovirus , Terapia Genética , Células Madre Pluripotentes Inducidas , Medicina de Precisión , Epitelio Pigmentado de la Retina , Humanos , Medicina de Precisión/métodos , Terapia Genética/métodos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Células Madre Pluripotentes Inducidas/metabolismo , Distrofias Hereditarias de la Córnea/terapia , Distrofias Hereditarias de la Córnea/genética , Distrofias Hereditarias de la Córnea/metabolismo , Distrofias Hereditarias de la Córnea/patología , Dependovirus/genética , Estrés Oxidativo/genética , Familia 4 del Citocromo P450/genética , Familia 4 del Citocromo P450/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Enfermedades de la Retina/terapia , Enfermedades de la Retina/genética , Enfermedades de la Retina/patología , Aldehídos/metabolismo , MasculinoRESUMEN
Gene therapies have emerged as promising treatments in clinical development for various retinal disorders, offering hope to patients with inherited degenerative eye conditions. Several gene therapies have already shown remarkable success in clinical trials, with significant improvements observed in visual acuity and the preservation of retinal function. A multitude of gene therapies have now been delivered safely in human clinical trials for a wide range of inherited retinal disorders but there are some gaps in the reported trial data. Some of the most exciting treatment options are not under peer review and information is only available in press release form. Whilst many trials appear to have delivered good outcomes of safety, others have failed to meet primary endpoints and therefore not proceeded to phase III. Despite this, such trials have enabled researchers to learn how best to assess and monitor patient outcomes, which will guide future trials to greater success. In this review, we consider recent and ongoing clinical trials for a variety of potential retinal gene therapy treatments and discuss the positive and negative issues related to these trials. We discuss the treatment potential following clinical trials as well as the potential risks of some treatments under investigation. As these therapies continue to advance through rigorous testing and regulatory approval processes, they hold the potential to revolutionise the landscape of retinal disorder treatments, providing renewed vision and enhancing the quality of life for countless individuals worldwide.
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Ensayos Clínicos como Asunto , Terapia Genética , Enfermedades de la Retina , Humanos , Terapia Genética/métodos , Enfermedades de la Retina/terapia , Enfermedades de la Retina/genética , Resultado del Tratamiento , Vectores GenéticosRESUMEN
INTRODUCTION: The purpose of this project was to explore the current standards of clinical care genetic testing and counseling for patients with inherited retinal diseases (IRDs) from the perspective of leading experts in selected European countries. Also, to gather opinions on current bottlenecks and future solutions to improve patient care. METHODS: On the initiative of the European Vision Institute, a survey questionnaire with 41 questions was designed and sent to experts in the field from ten European countries. Each participant was asked to answer with reference to the situation in their own country. RESULTS: Sixteen questionnaires were collected by November 2023. IRD genetic tests are performed in clinical care settings for 80% or more of tested patients in 9 countries, and the costs of genetic tests in clinical care are covered by the public health service to the extent of 90% or more in 8 countries. The median proportion of patients who are genetically tested, the median rate of genetically solved patients among those who are tested, and the median proportion of patients receiving counseling are 51-70%, 61-80%, and 61-80%, respectively. Improving the education of healthcare professionals who facilitate patient referrals to specialized centers, improving access of patients to more thorough genotyping, and increasing the number of available counselors were the most advocated solutions. CONCLUSION: There is a significant proportion of IRD patients who are not genetically tested, whose genetic testing is inconclusive, or who do not receive counseling. Educational programs, greater availability of state-of-the-art genotyping and genetic counselors could improve healthcare for IRD patients.
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Pruebas Genéticas , Enfermedades de la Retina , Humanos , Pruebas Genéticas/métodos , Europa (Continente) , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Encuestas y Cuestionarios , Asesoramiento GenéticoRESUMEN
RATIONALE: Autosomal recessive bestrophinopathy (ARB) is a subtype of bestrophinopathy caused by biallelic mutations of the BEST1 gene, which affect the retinal pigment epithelium (RPE). Studying RPE abnormalities through imaging is essential for understanding ARB. This case series involved the use of multimodal imaging techniques, namely autofluorescence (AF) imaging at 488 nm [short-wavelength AF] and 785 nm [near-infrared AF (NIR-AF)] and polarization-sensitive optical coherence tomography (PS-OCT), to investigate RPE changes in 2 siblings with ARB. PATIENT CONCERNS: Two Japanese siblings (Case 1: male, followed for 20-23 years; Case 2: female, followed for 13-17 years) carried compound heterozygous mutations of the BEST1 gene. DIAGNOSIS: Both siblings were diagnosed with ARB. INTERVENTIONS AND OUTCOMES: Multimodal imaging techniques were used to evaluate RPE changes. Both siblings had funduscopic changes similar to those seen in the vitelliruptive stage of Best vitelliform macular dystrophy during the follow-up period. NIR-AF imaging showed hypo-AF of the entire macular lesion in both cases, and this hypo-AF remained stable over time. PS-OCT confirmed reduced RPE melanin content in these hypo-AF areas. Additionally, hyper-NIR-AF dots were observed within hypo-NIR-AF areas. Concomitant identification of focally thickened RPE melanin on PS-OCT imaging and hyper-AF on short-wavelength AF imaging at the sites containing hyper-NIR-AF dots indicated that the hyper-NIR-AF dots had originated from either stacked RPE cells or RPE dysmorphia. LESSONS: We confirmed RPE abnormalities in ARB, including diffuse RPE melanin damage in the macula alongside evidence of RPE activity-related changes. This case series demonstrates that multimodal imaging, particularly NIR-AF and PS-OCT, provides detailed insights into RPE alterations in ARB.
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Bestrofinas , Enfermedades Hereditarias del Ojo , Imagen Multimodal , Enfermedades de la Retina , Epitelio Pigmentado de la Retina , Tomografía de Coherencia Óptica , Humanos , Imagen Multimodal/métodos , Masculino , Femenino , Tomografía de Coherencia Óptica/métodos , Enfermedades Hereditarias del Ojo/genética , Enfermedades Hereditarias del Ojo/diagnóstico por imagen , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/diagnóstico por imagen , Epitelio Pigmentado de la Retina/patología , Bestrofinas/genética , Adulto Joven , Imagen Óptica/métodos , Adolescente , HermanosRESUMEN
The gene therapy approach for retinal disorders has been considered largely over the last decade owing to the favorable outcomes of the US Food and Drug Administration-approved commercial gene therapy, Luxturna. Technological advances in recent years, such as next-generation sequencing, research in molecular pathogenesis of retinal disorders, and precise correlations with their clinical phenotypes, have contributed to the progress of gene therapies for various diseases worldwide, and more recently in India as well. Thus, considerable research is being conducted for the right choice of vectors, transgene engineering, and accessible and cost-effective large-scale vector production. Many retinal disease-specific clinical trials are presently being conducted, thereby necessitating the collation of such information as a ready reference for the scientific and clinical community. In this article, we present an overview of existing gene therapy research, which is derived from an extensive search across PubMed, Google Scholar, and clinicaltrials.gov sources. This contributes to prime the understanding of basic aspects of this cutting-edge technology and information regarding current clinical trials across many different conditions. This information will provide a comprehensive evaluation of therapies in existing use/research for personalized treatment approaches in retinal disorders.
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Terapia Genética , Enfermedades de la Retina , Humanos , Terapia Genética/métodos , Enfermedades de la Retina/terapia , Enfermedades de la Retina/genética , Vectores GenéticosRESUMEN
PURPOSE: Bietti crystalline dystrophy (BCD) is an inherited retinal degeneration disease caused by mutations in the CYP4V2 gene. Currently, there is no clinical therapy approach available for BCD patients. Previous research has suggested that polyunsaturated fatty acids (PUFAs) may play a significant role in the development of BCD, implicating the involvement of ferroptosis in disease pathogenesis. In this work, we aimed to investigate the interplay between ferroptosis and BCD and to detect potential therapeutic strategies for the disease. METHODS: Genetic-edited RPE cell line was first established in this study by CRISPR-Cas9 technology. Cyp4v3 (the homologous gene of human CYP4V2) knock out (KO) mice have also been used. Lipid profiling and transcriptome analysis of retinal pigment epithelium (RPE) cells from Cyp4v3 KO mice have been conducted. Ferroptosis phenotypes have been first investigated in BCD models in vitro and in vivo, including lipid peroxidation, mitochondrial changes, elevated levels of reactive oxygen species (ROS), and altered gene expression. Additionally, an iron chelator, deferiprone (DFP), has been tested in vitro and in vivo to determine its efficacy in suppressing ferroptosis and restoring the BCD phenotype. RESULTS: Cyp4v3 KO mice exhibited progressive retinal degeneration and lipid accumulation, similar to the BCD phenotype, which was exacerbated by a high-fat diet (HFD). Increased levels of PUFAs, such as EPA (C22:5) and AA (C20:4), were observed in the RPE of Cyp4v3 KO mice. Transcriptome analysis of RPE in Cyp4v3 KO mice revealed changes in genes involved in iron homeostasis, particularly an upregulation of NCOA4, which was confirmed by immunofluorescence. Ferroptosis-related characteristics, including mitochondrial defects, lipid peroxidation, ROS accumulation, and upregulation of related genes, were detected in the RPE both in vitro and in vivo. Abnormal accumulation of ferrous iron was also detected. DFP, an iron chelator administration suppressed ferroptosis phenotype in CYP4V2 mutated RPE. Oral administration of DFP also restored the retinal function and morphology in Cyp4v3 KO mice. CONCLUSION: This study represented the first evidence of the substantial role of ferroptosis in the development of BCD. PUFAs resulting from CYP4V2 mutation may serve as substrates for ferroptosis, potentially working in conjunction with NCOA4-regulated iron accumulation, ultimately leading to RPE degeneration. DFP administration, which chelates iron, has demonstrated its ability to reverse BCD phenotype both in vitro and in vivo, suggesting a promising therapeutic approach in the future.
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Distrofias Hereditarias de la Córnea , Ferroptosis , Ratones Noqueados , Epitelio Pigmentado de la Retina , Animales , Ferroptosis/genética , Ferroptosis/efectos de los fármacos , Distrofias Hereditarias de la Córnea/genética , Distrofias Hereditarias de la Córnea/patología , Distrofias Hereditarias de la Córnea/metabolismo , Distrofias Hereditarias de la Córnea/tratamiento farmacológico , Humanos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Epitelio Pigmentado de la Retina/efectos de los fármacos , Ratones , Especies Reactivas de Oxígeno/metabolismo , Enfermedades de la Retina/genética , Enfermedades de la Retina/patología , Enfermedades de la Retina/metabolismo , Enfermedades de la Retina/tratamiento farmacológico , Familia 4 del Citocromo P450/genética , Ratones Endogámicos C57BL , Línea Celular , Peroxidación de Lípido/efectos de los fármacosRESUMEN
Inherited retinal diseases (IRDs) are extremely heterogeneous with at least 350 causative genes, complicating the process of genetic diagnosis. We analyzed samples of 252 index cases with IRDs using the Blueprint Genetics panel for "Retinal Dystrophy" that includes 351 genes. The cause of disease could be identified in 55% of cases. A clear difference was obtained between newly recruited cases (74% solved) and cases that were previously analyzed by panels or whole exome sequencing (26% solved). As for the mode of inheritance, 75% of solved cases were autosomal recessive (AR), 10% were X-linked, 8% were autosomal dominant, and 7% were mitochondrial. Interestingly, in 12% of solved cases, structural variants (SVs) were identified as the cause of disease. The most commonly identified genes were ABCA4, EYS and USH2A, and the most common mutations were MAK-c.1297_1298ins353 and FAM161A-c.1355_1356del. In line with our previous IRD carrier analysis, we identified heterozygous AR mutations that were not the cause of disease in 36% of cases. The studied IRD panel was found to be efficient in gene identification. Some variants were misinterpreted by the pipeline, and therefore, multiple analysis tools are recommended to obtain a more accurate annotation of potential disease-causing variants.
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Mutación , Enfermedades de la Retina , Humanos , Masculino , Femenino , Enfermedades de la Retina/genética , Transportadoras de Casetes de Unión a ATP/genética , Proteínas del Ojo/genética , Pruebas Genéticas/métodos , Secuenciación del Exoma/métodos , Proteínas de la Matriz Extracelular/genética , Linaje , Distrofias Retinianas/genética , Predisposición Genética a la EnfermedadRESUMEN
PURPOSE: To provide a genotype and phenotype characterization of the BEST1 mutation in Chinese patients with autosomal recessive bestrophinopathy (ARB) through multimodal imaging and next-generation sequencing (NGS). METHODS: Seventeen patients from 17 unrelated families of Chinese origin with ARB were included in a retrospective cohort study. Phenotypic characteristics, including anterior segment features, were assessed by multimodal imaging. Multigene panel testing, involving 586 ophthalmic disease-associated genes, and Sanger sequencing were performed to identify disease-causing variants. RESULTS: Among 17 ARB patients, the mean follow-up was 15.65 months and average onset age was 30.53 years (range: 9-68). Best corrected visual acuity ranged from light perception to 0.8. EOG recordings showed a typically decreased Arden ratio in 12 patients, and a normal or slightly decreased Arden ratio in two patients. Anterior features included shallow anterior chambers (16/17), ciliary pronation (16/17), iris bombe (13/17), iridoschisis (2/17), iris plateau (1/17), narrow angles (16/17) and reduced axial lengths (16/17). Sixteen patients had multiple bilateral small, round, yellow vitelliform deposits distributed throughout the posterior pole, surrounding the optic disc. Initial diagnoses included angle-closure glaucoma (four patients), Best disease (three patients), and central serous chorioretinopathy secondary to choroidal neovascularization (CNV) (one patient), with the remainder diagnosed with ARB. Fourteen patients underwent preventive laser peripheral iridotomy, four of whom also received combined trabeculectomy and iridotomy in both eyes for uncontrolled intraocular pressure. One patient received intravitreal conbercept for CNV. Overall, 15 distinct disease-causing variants of BEST1 were identified, with 14 (82.35%) patients having missense mutations. Common mutations included p. Arg255-256 and p. Ala195Val (both 23.68%), with the most frequent sites in exons 7 and 5. CONCLUSIONS: This study provides a comprehensive characterization of anterior segment and genetic features in ARB, with a wide array of morphological abnormalities. Findings are relevant for refining clinical practices and genetic counseling and advancing pathogenesis research.
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Bestrofinas , Enfermedades Hereditarias del Ojo , Agudeza Visual , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Bestrofinas/genética , China/epidemiología , Análisis Mutacional de ADN , Pueblos del Este de Asia , Electrooculografía , Electrorretinografía , Enfermedades Hereditarias del Ojo/genética , Enfermedades Hereditarias del Ojo/diagnóstico , Estudios de Seguimiento , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Imagen Multimodal , Mutación , Linaje , Fenotipo , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual/fisiologíaRESUMEN
Purpose: Recent studies have shown that the retinal pigment epithelium (RPE) relies on fatty acid oxidation (FAO) for energy, however, its role in overall retinal health is unknown. The only FAO disorder that presents with chorioretinopathy is long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). Studying the molecular mechanisms can lead to new treatments for patients and elucidate the role of FAO in the RPE. This paper characterizes the chorioretinopathy progression in a recently reported LCHADD mouse model. Methods: Visual assessments, such as optokinetic tracking and fundus imaging, were performed in wildtype (WT) and LCHADD mice at 3, 6, 10, and 12 months of age. Retinal morphology was analyzed in 12-month retinal cross-sections using hematoxylin and eosin (H&E), RPE65, CD68, and TUNEL staining, whereas RPE structure was assessed using transmission electron microscopy (TEM). Acylcarnitine profiles were measured in isolated RPE/sclera samples to determine if FAO was blocked. Bulk RNA-sequencing of 12 month old male WT mice and LCHADD RPE/sclera samples assessed gene expression changes. Results: LCHADD RPE/sclera samples had a 5- to 7-fold increase in long-chain hydroxyacylcarnitines compared to WT, suggesting an impaired LCHAD step in long-chain FAO. LCHADD mice have progressively decreased visual performance and increased RPE degeneration starting at 6 months. LCHADD RPE have an altered structure and a two-fold increase in macrophages in the subretinal space. Finally, LCHADD RPE/sclera have differentially expressed genes compared to WT, including downregulation of genes important for RPE function and angiogenesis. Conclusions: Overall, this LCHADD mouse model recapitulates early-stage chorioretinopathy seen in patients with LCHADD and is a useful model for studying LCHADD chorioretinopathy.
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Modelos Animales de Enfermedad , Epitelio Pigmentado de la Retina , Animales , Ratones , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Ratones Endogámicos C57BL , 3-Hidroxiacil-CoA Deshidrogenasa de Cadena Larga/metabolismo , Enfermedades de la Coroides/genética , Enfermedades de la Coroides/metabolismo , Masculino , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Enfermedades de la Retina/fisiopatología , Microscopía Electrónica de TransmisiónRESUMEN
ABCA4 is the most frequently mutated gene leading to inherited retinal disease (IRD) with over 2200 pathogenic variants reported to date. Of these, ~1% are copy number variants (CNVs) involving the deletion or duplication of genomic regions, typically >50 nucleotides in length. An in-depth assessment of the current literature based on the public database LOVD, regarding the presence of known CNVs and structural variants in ABCA4, and additional sequencing analysis of ABCA4 using single-molecule Molecular Inversion Probes (smMIPs) for 148 probands highlighted recurrent and novel CNVs associated with ABCA4-associated retinopathies. An analysis of the coverage depth in the sequencing data led to the identification of eleven deletions (six novel and five recurrent), three duplications (one novel and two recurrent) and one complex CNV. Of particular interest was the identification of a complex defect, i.e., a 15.3 kb duplicated segment encompassing exon 31 through intron 41 that was inserted at the junction of a downstream 2.7 kb deletion encompassing intron 44 through intron 47. In addition, we identified a 7.0 kb tandem duplication of intron 1 in three cases. The identification of CNVs in ABCA4 can provide patients and their families with a genetic diagnosis whilst expanding our understanding of the complexity of diseases caused by ABCA4 variants.
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Transportadoras de Casetes de Unión a ATP , Variaciones en el Número de Copia de ADN , Enfermedades de la Retina , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Enfermedades de la Retina/genética , Femenino , Masculino , Linaje , Intrones/genética , Exones/genética , Duplicación de GenRESUMEN
Mutations in the CRB1 gene are associated with a diverse spectrum of retinopathies with phenotypic variability causing severe visual impairment. The CRB1 gene has a role in retinal development and is expressed in the cerebral cortex and hippocampus, but its role in cognition has not been described before. This study compares cognitive function in CRB1 retinopathy individuals with subjects with other retinopathies and the normal population. METHODS: Neuropsychological tests of cognitive function were used to test individuals with CRB1 and non-CRB1 retinopathies and compare results with a standardised normative dataset. RESULTS: CRB1 retinopathy subjects significantly outperformed those with non-CRB1 retinopathy in list learning tasks of immediate (p = 0.001) and delayed memory (p = 0.007), tests of semantic verbal fluency (p = 0.017), verbal IQ digit span subtest (p = 0.037), and estimation test of higher execution function (p = 0.020) but not in the remaining tests of cognitive function (p > 0.05). CRB1 retinopathy subjects scored significantly higher than the normal population in all areas of memory testing (p < 0.05) and overall verbal IQ tests (p = 0.0012). Non-CRB1 retinopathy subjects scored significantly higher than the normal population in story recall, verbal fluency, and overall verbal IQ tests (p = 0.0016). CONCLUSIONS: Subjects with CRB1 retinopathy may have enhanced cognitive function in areas of memory and learning. Further work is required to understand the role of CRB1 in cognition.
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Proteínas del Ojo , Proteínas de la Membrana , Memoria , Proteínas del Tejido Nervioso , Humanos , Proteínas del Tejido Nervioso/genética , Masculino , Femenino , Proteínas de la Membrana/genética , Adulto , Persona de Mediana Edad , Proteínas del Ojo/genética , Memoria/fisiología , Enfermedades de la Retina/genética , Pruebas Neuropsicológicas , Cognición , Aprendizaje/fisiología , Adulto Joven , Adolescente , AncianoRESUMEN
Inherited retinal diseases (IRDs) are a large group of genetically and clinically diverse blinding eye conditions that result in progressive and irreversible photoreceptor degeneration and vision loss. To date, no cures have been found, although strides toward treatments for specific IRDs have been made in recent years. To accelerate treatment discovery, retinal organoids provide an ideal human IRD model. This review aims to give background on the development and importance of retinal organoids for the human-based in vitro study of the retina and human retinogenesis and retinal pathologies. From there, we explore retinal pathologies in the context of IRDs and the current landscape of IRD treatment discovery. We discuss the usefulness of retinal organoids in this context (as a patient-derived cell model for IRDs) to precisely understand the pathogenesis and potential mechanisms behind a specific IRD-causing variant of interest. Finally, we discuss the importance and promise of retinal organoids in treatment discovery for IRDs, now and in the future.
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Organoides , Retina , Enfermedades de la Retina , Humanos , Enfermedades de la Retina/genética , Enfermedades de la Retina/patología , Retina/metabolismo , Retina/patología , AnimalesRESUMEN
The purpose of this study was to assess the added diagnostic value of whole genome sequencing (WGS) for patients with inherited retinal diseases (IRDs) who remained undiagnosed after whole exome sequencing (WES). WGS was performed for index patients in 66 families. The datasets were analyzed according to GATK's guidelines. Additionally, DeepVariant was complemented by GATK's workflow, and a novel structural variant pipeline was developed. Overall, a molecular diagnosis was established in 19/66 (28.8%) index patients. Pathogenic deletions and one deep-intronic variant contributed to the diagnostic yield in 4/19 and 1/19 index patients, respectively. The remaining diagnoses (14/19) were attributed to exonic variants that were missed during WES analysis due to bioinformatic limitations, newly described loci, or unclear pathogenicity. The added diagnostic value of WGS equals 5/66 (9.6%) for our cohort, which is comparable to previous studies. This figure would decrease further to 1/66 (1.5%) with a standardized and reliable copy number variant workflow during WES analysis. Given the higher costs and limited added value, the implementation of WGS as a first-tier assay for inherited eye disorders in a diagnostic laboratory remains untimely. Instead, progress in bioinformatic tools and communication between diagnostic and clinical teams have the potential to ameliorate diagnostic yields.
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Pruebas Genéticas , Enfermedades de la Retina , Secuenciación Completa del Genoma , Humanos , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Pruebas Genéticas/métodos , Secuenciación Completa del Genoma/métodos , Masculino , Femenino , Suiza , Estudios de Cohortes , Adulto , Variaciones en el Número de Copia de ADN , Secuenciación del Exoma/métodos , Biología Computacional/métodos , Persona de Mediana Edad , Niño , Adolescente , LinajeRESUMEN
The dog retina contains a central macula-like region, and there are reports of central retinal disorders in dogs with shared genetic etiologies with humans. Defining central/peripheral gene expression profiles may provide insight into the suitability of dogs as models for human disorders. We determined central/peripheral posterior eye gene expression profiles in dogs and interrogated inherited retinal and macular disease-associated genes for differential expression between central and peripheral regions. Bulk tissue RNA sequencing was performed on 8 mm samples of the dog central and superior peripheral regions, sampling retina and retinal pigmented epithelium/choroid separately. Reads were mapped to CanFam3.1, read counts were analyzed to determine significantly differentially expressed genes (DEGs). A similar analytic pipeline was used with a published bulk-tissue RNA sequencing human dataset. Pathways and processes involved in significantly DEGs were identified (Database for Annotation, Visualization and Integrated Discovery). Dogs and humans shared the extent and direction of central retinal differential gene expression, with multiple shared biological pathways implicated in differential expression. Many genes implicated in heritable retinal disorders in dogs and humans were differentially expressed between central and periphery. Approximately half of genes associated with human age-related macular degeneration were differentially expressed in human and dog tissues. We have identified similarities and differences in central/peripheral gene expression profiles between dogs and humans which can be applied to further define the relevance of dogs as models for human retinal disorders.
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Retina , Perros , Animales , Humanos , Retina/metabolismo , Regulación de la Expresión Génica/fisiología , Perfilación de la Expresión Génica , Modelos Animales de Enfermedad , Transcriptoma , Epitelio Pigmentado de la Retina/metabolismo , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Masculino , Femenino , Coroides/metabolismoRESUMEN
Given the absence of approved treatments for pathogenic variants in Peripherin-2 (PRPH2), it is imperative to identify a universally effective therapeutic target for PRPH2 pathogenic variants. To test the hypothesis that formation of the elongated discs in presence of PRPH2 pathogenic variants is due to the presence of the full complement of rhodopsin in absence of the required amounts of functional PRPH2. Here we demonstrate the therapeutic potential of reducing rhodopsin levels in ameliorating disease phenotype in knockin models for p.Lys154del (c.458-460del) and p.Tyr141Cys (c.422 A > G) in PRPH2. Reducing rhodopsin levels improves physiological function, mitigates the severity of disc abnormalities, and decreases retinal gliosis. Additionally, intravitreal injections of a rhodopsin-specific antisense oligonucleotide successfully enhance the physiological function of photoreceptors and improves the ultrastructure of discs in mutant mice. Presented findings shows that reducing rhodopsin levels is an effective therapeutic strategy for the treatment of inherited retinal degeneration associated with PRPH2 pathogenic variants.
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Periferinas , Rodopsina , Periferinas/genética , Periferinas/metabolismo , Animales , Rodopsina/genética , Rodopsina/metabolismo , Ratones , Humanos , Modelos Animales de Enfermedad , Regulación hacia Abajo , Degeneración Retiniana/genética , Degeneración Retiniana/metabolismo , Degeneración Retiniana/terapia , Oligonucleótidos Antisentido/genética , Retina/metabolismo , Retina/patología , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Enfermedades de la Retina/patología , Enfermedades de la Retina/terapia , Ratones Endogámicos C57BL , Mutación , Femenino , Técnicas de Sustitución del Gen , MasculinoRESUMEN
Over the past twenty years, ocular gene therapy has primarily focused on addressing diseases linked to various genetic factors. The eye is an ideal candidate for gene therapy due to its unique characteristics, such as easy accessibility and the ability to target both corneal and retinal conditions, including retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), age-related macular degeneration (AMD), and Stargardt disease. Currently, literature documents 33 clinical trials in this field, with the most promising results emerging from trials focused on LCA. These successes have catalyzed further research into other ocular conditions such as glaucoma, AMD, RP, and choroideremia. The effectiveness of gene therapy relies on the efficient delivery of genetic material to specific cells, ensuring sustained and optimal gene expression over time. Viral vectors have been widely used for this purpose, although concerns about potential risks such as immune reactions and genetic mutations have led to the development of non-viral vector systems. Preliminary laboratory research and clinical investigations have shown a connection between vector dosage and the intensity of immune response and inflammation in the eye. The method of administration significantly influences these reactions, with subretinal delivery resulting in a milder humoral response compared to the intravitreal route. This review discusses various ophthalmic diseases, including both corneal and retinal conditions, and their underlying mechanisms, highlighting recent advances and applications in ocular gene therapies.