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BACKGROUND: To describe the phenotype and genotype of 10 Brazilian patients with variants in MFRP, posterior microphthalmos and retinal findings. METHODS: Complete ophthalmological evaluation was done at 4 different Brazilian centers. Genetic analysis was performed using commercial next generation sequencing panels for inherited retinal disorders. RESULTS: Ages of the patients ranged from 10 to 65 years and visual acuities from 0,05 to no perception of light. All were hyperopes (+4,25 to + 17,50) with a short axial length (14,4 mm to 18 mm). Common posterior segment features, though not present in all, were optic disc drusen (5/10), foveoschisis (5/10) and retinal pigmentary changes (8/10). Isolated patients presented with macular atrophy, serous retinal detachment, and chorioretinal folds. The most common variant in MFRP found in our patients was a deletion in exon 5 (c.498delC; p.Asn267Thrfs *25), present in all except 2 patients. Other variants found were c.523C>T (p.Gln175*), c.298delG (p.Ala100Argfs *37), c.666del (p.Thr223Argfs *83) and the novel variant c.257C>A (p.Ala86Asp). CONCLUSIONS: This is the first report of Brazilian patients with posterior microphthalmos and pathogenic variants in MFRP and the first describe of the variant p.Ala86Asp in literature. Our cases confirm the previously reported phenotype of high hyperopia, optic disc drusen, alterations in foveal architecture, retinal pigmentary changes with loss of photoreceptor function and visual field constriction. Report of such a rare condition is important to increase awareness to the phenotype of posterior microphthalmia with associated retinal conditions.

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BACKGROUND: Inherited retinal dystrophies are hereditary diseases which have in common the progressive degeneration of photoreceptors. They are a group of diseases with clinical, genetic, and allelic heterogeneity. There is limited information regarding the genetic landscape of inherited retinal diseases in Mexico, therefore, the present study was conducted in the northeast region of the country. METHODS: Patients with inherited retinal dystrophies were included. A complete history, full ophthalmological and medical genetics evaluations, and genetic analysis through a targeted NGS panel for inherited retinal dystrophies comprising at least 293 genes were undertaken. RESULTS: A total of 126 patients were included. Cases were solved in 74.6% of the study's population. Retinitis pigmentosa accounted for the most found inherited retinal disease. Ninety-nine causal variants were found, being USH2A and ABCA4 the most affected genes (26 and 15 cases, respectively). CONCLUSIONS: The present study documents the most prevalent causative genes in IRDs, as USH2A, in northeastern Mexico. This contrasts with previous reports of IRDs in other zones of the country. Further studies, targeting previously unstudied populations in Mexico are important to document the genetic background of inherited retinal dystrophies in the country.

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ABSTRACT Purpose: Stargardt-like phenotype has been described as associated with pathogenic variants besides the ABCA4 gene. This study aimed to describe four cases with retinal appearance of Stargardt disease phenotypes and unexpected molecular findings. Methods: This report reviewed medical records of four patients with macular dystrophy and clinical features of Stargardt disease. Ophthalmic examination, fundus imaging, and next-generation sequencing were performed to evaluate pathogenic variants related to the phenotypes. Results: Patients presented macular atrophy and pigmentary changes suggesting Stargardt disease. The phenotypes of the two patients were associated with autosomal dominant inheritance pattern genes (RIMS1 and CRX) and in the other two patients were associated with recessive dominant inheritance pattern genes (CRB1 and RDH12) with variants predicted to be pathogenic. Conclusion: Macular dystrophies may have phenotypic similarities to Stargardt-like phenotype associated with other genes besides the classic ones.

RESUMO Objetivo: Fenótipos Stargardt-like já foram asso-ciados a variantes patogênicas no gene ABCA4. O propósito desse estudo é descrever quatro pacientes com achados retinianos semelhantes a doença de Stargardt com resultados moleculares diferentes do esperado. Métodos: Esse relato fez a revisão de prontuários médicos de quatro pacientes com distrofia macular e achados clínicos sugestivos de doença de Stargardt. Foram realizados avaliação oftalmológica, exames de imagens e testes usando next generation sequencing para avaliar variantes patogênicas associadas aos fenótipos dos pacientes. Resultados: Os pacientes apresentavam atrofia macular e alterações pigmentares sugerindo achados clínicos de doença de Stargardt. Dois pacientes foram associados a genes com herança autossômica dominante (RIMS1 e CRX) e dois pacientes foram associados a genes com herança autossômica recessiva (CRB1 e RDH12) com variantes preditoras de serem patogênicas. Conclusão: Distrofias maculares podem ter similaridades fenotípicas com fenótipo de Stargardt-like associados a outros genes além dos classicamente já descritos.

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OBJECTIVE: To evaluate the possibility of gene therapy in patients with inherited ocular conditions and established genetic diagnosis. The secondary objectives were to determine the genetic diagnostic rate and to update the list of genes for which there are ongoing clinical trials or preclinical studies that could allow for gene therapy. METHODS: Observational, retrospective, multicentric study of 177 patients with inherited ocular conditions that underwent genetic testing. RESULTS: Of 177 patients with genetic testing, 146 were enrolled for this study. Disease-causing variants were identified in 117 patients (variant detection rate of 80.1%). Pathogenic variants were found in 47 genes, with ABCA4 being the most common gene (17.9%), followed by CRB1 (11.9%). 64.1% of patients with a genetic diagnosis have a variant in genes for which gene therapy has been studied and only 40.1% have a variant in genes with studies for gene therapy in clinical phase. CONCLUSIONS: Genetic testing has opened new horizons in the management of patients with hereditary ocular diseases. About two-thirds of the patients had pathogenic variants in genes for which gene therapy has been evaluated. However, many studies are in the pre-clinical phase. The expectations of patients undergoing genetic study and their families should be managed accordingly.

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RESUMO A amaurose congênita de Leber, também conhecida como neuropatia óptica hereditária de Leber, é caracterizada por uma das formas mais graves de distrofia da retina com início na infância. Os achados clássicos são deficiência visual grave e precoce, nistagmo e eletrorretinograma (ERG) anormal ou não detectável. O objetivo deste estudo é relatar um caso de um paciente com amaurose congênita de Leber com comprometimento visual desde os 6 meses de vida e acentuado declínio visual a partir dos 15 anos de idade. A realização de exames específicos para confirmar o diagnóstico é importante para o manejo e o seguimento adequado do paciente e para proporcionar melhor qualidade de vida para o mesmo.

ABSTRACT Leber Congenital Amaurosis, also known as Leber hereditary optic neuropathy, is characterized by one of the most severe forms of childhood-onset retinal dystrophy. Classic findings are severe and early visual impairment, nystagmus, and abnormal or undetectable electroretinogram. The aim of this study is to report a case of a patient with Leber Congenital Amaurosis with visual impairment since the first six months of age and marked visual decline from fifteen years of age. Performing specific tests to confirm the diagnosis is important for the proper management and follow-up of the patient and to provide them with a better quality of life.

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PURPOSE: To compare the vision-specific quality of life (QoL) of individuals with Stargardt disease (STGD) with that of healthy individuals and to investigate the association between vision-specific QoL and functional vision. METHODS: This cross-sectional study included 41 patients with STGD and 46 healthy volunteers matched by age and gender. Best corrected visual acuity (BCVA) was used to calculate the Functional Acuity Score (FAS) and Goldmann perimetry the Functional Field Score (FFS). These scores were combined to obtain the Functional Vision Score (FVS). Vision-specific QoL was assessed using the 25-item version of the National Eye Institute Visual Function Questionnaire (NEI VFQ-25). RESULTS: The groups had similar sociodemographic and clinical characteristics. There were significant differences in BCVA, vision-specific QoL assessed by the NEI VFQ-25, and FVS (p < 0.001) between individuals with STGD and controls. The final total score and all the subscales of the NEI VQF-25 questionnaire were significantly lower in the STGD group (p < 0.001), except for the subscales general health, color vision, and ocular pain. NEI VFQ-25 results in the STGD group were positively correlated with family income, FVS, and FFS. FVS was the score best correlated with the NEI VFQ-25 total score. CONCLUSIONS: Individuals with STGD had significant impairment of vision-specific QoL and functional vision compared with controls and the FVS was the objective evaluation method most correlated with vision-specific QoL in this population.

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PURPOSE: To report the first Brazilian patient with RPE65 deficiency-inherited retinal dystrophy (RPE65-IRD) treated with voretigene neparvovec-rzyl (VN). METHODS: An adult patient with Leber congenital amaurosis-2 with a homozygous mutation in the RPE65 gene (p.Phe83Leu) was treated bilaterally with VN. The clinical and surgical aspects are described. The baseline and 4-month postoperative ophthalmologic examinations included measurement of the best-corrected visual acuity (BCVA), full-field stimulus threshold (FST) test, Octopus 900 semiautomated kinetic visual fields (VFs), and microperimetry. RESULTS: No complications developed in this patient. The BCVA remained stable. The full-field stimulus threshold test (FST) and VFs showed clinically significant improvements bilaterally. The patient reported significant improvements in the ability to perform daily activities, mainly for those requiring the VFs and vision in a low-luminescence environment. CONCLUSIONS: The treatments were beneficial for this patient who was homozygous for RPE65 p.Phe83Leu. The first VN treatments in an adult Brazilian patient in clinical practice showed measurable improvements in visual outcomes that were meaningful for the patient's daily activities. TRANSLATIONAL RELEVANCE: This case reinforces the clinical trial results and proves that the procedure is feasible in countries such as Brazil.

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INTRODUCTION: Inherited retinal dystrophies (IRDs) represent a genetically diverse group of progressive, visually debilitating diseases. Adult and paediatric patients with vision loss due to IRD caused by biallelic mutations in the 65-kDa retinal pigment epithelium (RPE65) gene are often clinically diagnosed as retinitis pigmentosa (RP), and Leber congenital amaurosis (LCA). This study aimed to understand the epidemiological landscape of RPE65 gene-mediated IRD through a systematic review of the literature, as the current evidence base for its epidemiology is very limited. METHODS: Medline, Embase, and other databases were searched for articles on the epidemiology of RPE65 gene-mediated IRDs from inception until June 2021. Studies were included if they were original research articles reporting the epidemiology of RP and LCA and/or proportion of RPE65 gene mutations in these clinically diagnosed or molecularly confirmed IRDs patients. RESULTS: A total of 100 studies with relevant data were included in this systematic review. The range for prevalence of LCA and RP in the literature was 1.20-2.37 and 11.09-26.43 per 100,000, respectively. The proportion of RPE65 mutations in clinically diagnosed patients with LCA was found to be between ~ 2-16% within the US and major European countries (France, Germany, Italy, Spain, and the UK). This range was also comparable to our findings in the Asian region for RPE65-LCA (1.26-16.67%). Similarly, for these European countries, RPE65-RP was estimated between 0.23 and 1.94%, and RPE65-IRD range was 1.2-14%. Further, in the Americas region, mutations in RPE65 were reported to cause 1-3% of RP and 0.8-3.7% of IRD cases. Lastly, the RPE65-IRD range was 4.81-8% in the Middle East region. CONCLUSIONS: There are significant variations in reporting of RPE65 proportions within countries as well as regions. Generating robust epidemiological evidence on RPE65 gene-mediated IRDs would be fundamental to support rare disease awareness, timely therapeutic intervention, and public health decision-making.

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BACKGROUND: X-linked retinoschisis (XLRS) is a rare retinal dystrophy due to pathogenic variants in the RS1 gene. The hallmark of the disease is a foveal spoke-wheel appearance. The purpose of this report is to expand the phenotypic spectrum of XLRS reporting a patient with atypical phenotype of XLRS associated with Coats-like phenotype. MATERIALS AND METHODS: This is a case report of a patient diagnosed with XLRS who underwent ophthalmologic multimodal imaging and next-generation sequencing panel. RESULTS: The proband is a 14-year-old male patient who presented at Instituto Suel Abujamra with a history of Coats Disease in the right eye treated with retinal laser in both eyes two years ago. His best-corrected visual acuity was count finger at 1 foot in the right eye and 20/40 in the left eye. Fundus exam showed an extensive area of exudation and retinal detachment in the right eye and cystic change at the fovea in a spoke-wheel pattern in the left eye. The next-generation sequencing panel targeting inherited retinal diseases with 236 genes found a pathogenic hemizygous variant c.304C>T (p.Arg102Trp) in RS1 that has already been reported. CONCLUSIONS: The association of peripheral vascular incompetence and XLRS has already been described. Retinal exudation in the setting of XLRS is probably the result of vascular disruption and compromise. The loss of retinoschisin function that leads to foveal retinoschisis may also lead to vascular anomalies.

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ABSTRACT Reticular pigmentary retinal dystrophy, also known as Sjögren's reticular dystrophy, is a rare condition characterized by macular lesions with a reticular pattern, which are best seen on fluorescein angiogram. Choroidal neovascularization secondary to this type of dystrophy is even less common. This report describes a case of reticular pigmentary retinal dystrophy with vision loss due to neovascular membrane, which responded well to treatment with anti-vascular endothelial growth factor.

RESUMO A distrofia reticular pigmentar da retina, também conhecida como distrofia reticular de Sjögren, é uma doença rara, caracterizada por lesões maculares com um padrão reticular, que são mais bem visualizadas na angiografia com fluoresceína. A neovascularização de coroide secundária a este tipo de distrofia é ainda menos comum. Este relato descreve um caso de distrofia reticular pigmentar da retina, com perda de visão devido à membrana neovascular, que respondeu bem ao tratamento com fator de crescimento endotelial antivascular.

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In this work, we aimed to provide the genetic diagnosis of a large cohort of patients affected with inherited retinal dystrophies (IRDs) from Mexico. Our data add valuable information to the genetic portrait in rare ocular diseases of Mesoamerican populations, which are mostly under-represented in genetic studies. A cohort of 144 unrelated probands with a clinical diagnosis of IRD were analyzed by next-generation sequencing using target gene panels (overall including 346 genes and 65 intronic sequences). Four unsolved cases were analyzed by whole-exome sequencing (WES). The pathogenicity of new variants was assessed by in silico prediction algorithms and classified following the American College of Medical Genetics and Genomics (ACMG) guidelines. Pathogenic or likely pathogenic variants were identified in 105 probands, with a final diagnostic yield of 72.9%; 17 cases (11.8%) were partially solved. Eighteen patients were clinically reclassified after a genetic diagnostic test (17.1%). In our Mexican cohort, mutations in 48 genes were found, with ABCA4, CRB1, RPGR and USH2A as the major contributors. Notably, over 50 new putatively pathogenic variants were identified. Our data highlight cases with relevant clinical and genetic features due to mutations in the RAB28 and CWC27 genes, enrich the novel mutation repertoire and expand the IRD landscape of the Mexican population.

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The malattia leventinese is an autosomal dominant inherited disease whose symptoms appear between the second and fourth decades of life. It is characterized by the appearance of drusen located between the retinal pigment epithelium and the Bruch membrane. It is usually associated with low vision and may progress to blindness. The pathogenic variant p.Arg345Trp in the EFEMP1 gene has been associated with this disease. We characterized clinically and molecularly a family with malattia leventinese using a comprehensive approach that involved ophthalmologists, pediatricians, and geneticists. This approach is of great importance since the phenotype of this disease is often confused with acular degeneration. All family members underwent ophthalmological evaluation and DNA extraction from a peripheral blood sample. All exons of the EFEMP1 gene were amplified and sequenced. The pathogenic variant p.Arg345Trp was identified in affected individuals in this family. This is the first report of malattia leventinese in a family with the p.Arg345Trp pathogenic variant in Colombia. The molecular diagnosis of retinal dystrophies is essential to differentiate this type of pathology.

La malattia leventinese es una enfermedad hereditaria autosómica dominante, cuyos síntomas se inician entre la segunda y la cuarta décadas de la vida. Se caracteriza por la aparición de drusas localizadas entre el epitelio pigmentario de la retina y la membrana de Bruch; suele reducir la visión drásticamente y progresar a ceguera. La variante patogénica p.Arg345Trp en el gen EFEMP1 se ha asociado con esta enfermedad. Se presenta aquí la caracterización clínica y molecular de una familia con malattia leventinese mediante un manejo integral que involucró a oftalmólogos, pediatras y genetistas, lo que es de gran importancia, ya que el fenotipo de esta enfermedad suele confundirse con la degeneración macular. A todos los individuos de la familia se les hizo la evaluación oftalmológica con imágenes diagnósticas de retina y extracción de ADN a partir de una muestra de sangre periférica. Todos los exones del gen EFEMP1 se amplificaron y secuenciaron. La variante patogénica p.Arg345Trp se identificó en los individuos afectados. Este es el primer reporte de malattia leventinese en una familia con la variante patogénica p.Arg345Trp en Colombia. El diagnóstico molecular de las distrofias retinianas es fundamental para diferenciar este tipo de enfermedades.

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Resumen La malattia leventinese es una enfermedad hereditaria autosómica dominante, cuyos síntomas se inician entre la segunda y la cuarta décadas de la vida. Se caracteriza por la aparición de drusas localizadas entre el epitelio pigmentario de la retina y la membrana de Bruch; suele reducir la visión drásticamente y progresar a ceguera. La variante patogénica p.Arg345Trp en el gen EFEMP1 se ha asociado con esta enfermedad. Se presenta aquí la caracterización clínica y molecular de una familia con malattia leventinese mediante un manejo integral que involucró a oftalmólogos, pediatras y genetistas, lo que es de gran importancia, ya que el fenotipo de esta enfermedad suele confundirse con la degeneración macular. A todos los individuos de la familia se les hizo la evaluación oftalmológica con imágenes diagnósticas de retina y extracción de ADN a partir de una muestra de sangre periférica. Todos los exones del gen EFEMP1 se amplificaron y secuenciaron. La variante patogénica p.Arg345Trp se identificó en los individuos afectados. Este es el primer reporte de malattia leventinese en una familia con la variante patogénica p.Arg345Trp en Colombia. El diagnóstico molecular de las distrofias retinianas es fundamental para diferenciar este tipo de enfermedades.

Abstract The malattia leventinese is an autosomal dominant inherited disease whose symptoms appear between the second and fourth decades of life. It is characterized by the appearance of drusen located between the retinal pigment epithelium and the Bruch membrane. It is usually associated with low vision and may progress to blindness. The pathogenic variant p.Arg345Trp in the EFEMP1 gene has been associated with this disease. We characterized clinically and molecularly a family with malattia leventinese using a comprehensive approach that involved ophthalmologists, pediatricians, and geneticists. This approach is of great importance since the phenotype of this disease is often confused with macular degeneration. All family members underwent ophthalmological evaluation and DNA extraction from a peripheral blood sample. All exons of the EFEMP1 gene were amplified and sequenced. The pathogenic variant p.Arg345Trp was identified in affected individuals in this family. This is the first report of malattia leventinese in a family with the p.Arg345Trp pathogenic variant in Colombia. The molecular diagnosis of retinal dystrophies is essential to differentiate this type of pathology.

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ABSTRACT Mutations in the ABCA4 gene are a common cause of Stargardt disease; however, other retinal phenotypes have also been associated with mutations in this gene. We describe an observational case report of an unusual clinical phenotype of Stargardt disease. The ophthalmological examination included best corrected visual acuity, color and autofluorescence photography, fluorescein angiography, optical coherence tomography, and electrophysiology tests. Targeted next-generation sequencing of 99 genes associated with inherited retinal dystrophies was performed in the index patient. A 48-year-old woman presented with a best corrected visual acuity of 20/25 and 20/20. Fundoscopy revealed perifoveal yellow flecked-like lesions. Fluorescein angiography and fundus autofluorescence findings were consistent with pattern dystrophy. Pattern electroretinogram demonstrated bilateral decrease of p50 values. Genetic testing identified two heterozygous missense mutations, c.428C>T, p.(Pro143Leu) and c.3113C>T, p.(Ala.1038Val), in the ABCA4 gene. Based on our results, we believe that these particular mutations in the ABCA4 gene could be associated with a specific disease phenotype characterized by funduscopic appearance similar to pattern dystrophy. A detailed characterization of the retinal phenotype in patients carrying specific mutations in ABCA4 is crucial to understand disease expression and ensure optimal clinical care for patients with inherited retinal dystrophies.

RESUMO Mutações no gene ABCA4 são causa comum da doença de Stargardt, mas outros fenótipos da retina também foram associados a mutações nesse gene. Apresentamos um relato de caso observacional de um fenótipo clínico incomum da doença de Stargardt. O exame oftalmológico incluiu a acuidade visual com melhor correção, fotografia em cores e com autofluorescência, angiofluoresceinografia, tomografia de coerência óptica e testes de eletrofisiologia. Na paciente em questão, realizou-se o sequenciamento de próxima geração de 99 genes associados a distrofias retinais hereditárias. Tratava-se de uma mulher de 48 anos com melhor acuidade visual corrigida de 20/25 e 20/20. A fundoscopia revelou lesões puntiformes amarelas perifoveais. Os resultados da angiofluoresceinografia e da autofluorescência do fundo de olho foram consistentes com distrofia em padrão. A eletrorretinografia por padrões mostrou diminuição bilateral dos valores de p50. Os testes genéticos revelaram duas mutações missense heterozigóticas, c.428C>T, p. (Pro143Leu) e c.3113C>T, p. (Ala.1038Val), no gene ABCA4. Nossos resultados nos fazem pensar que essas mutações específicas em ABCA4 talvez possam estar associadas a um fenótipo específico da doença, caracterizado por uma aparência fundoscópica semelhante à da distrofia em padrão. Uma caracterização detalhada do fenótipo da retina em pacientes portadores de mutações específicas em ABCA4 é crucial para compreender a expressão da doença e para garantir o tratamento clínico ideal para pacientes com distrofias retinais hereditárias.

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BACKGROUND: Retinal dystrophies constitute a group of diseases characterized by clinical variability and pronounced genetic heterogeneity. Retinitis pigmentosa is the most common subtype of hereditary retinal dystrophy and is characterized by a progressive loss of peripheral field vision (Tunnel Vision), eventual loss of central vision, and progressive night blindness. The characteristics of the fundus changes include bone-spicule formations, attenuated blood vessels, reduced and/or abnormal electroretinograms, changes in structure imaged by optical coherence tomography, and subjective changes in visual function. The different syndromic and nonsyndromic forms of retinal dystrophies can be attributed to mutations in more than 250 genes. Molecular diagnosis for patients with retinitis pigmentosa has been hampered by extreme genetic and clinical heterogeneity between retinitis pigmentosa and other forms of retinal dystrophies. Next generation sequencing (NGS) technologies are among the most promising techniques to identify pathogenic variations in retinal dystrophies. PURPOSE: The purpose of this study was to discover the molecular diagnosis for Brazilian patients clinically diagnosed with a retinitis pigmentosa pattern of inheritance by using NGS technologies. MATERIALS AND METHODS: Sixteen patients with the clinical diagnosis of retinitis pigmentosa were included in the study. Their DNA was sequenced in a panel with 132 genes related to retinal dystrophies using the Illumina® platform. Sequence analysis and variation calling was performed using Soft Genetics®, NextGene, and Geneticist Assistant software. The criteria for pathogenicity analysis were established according to the results of prediction programs (Polyphen 2, Mutation taster and MetaCore™) and comparison of pathogenic variations found with databases. RESULTS: The identified potentially pathogenic variations were all confirmed by Sanger sequencing. There were 89 variations predicted as pathogenic, but only 10 of them supported the conclusion of the molecular diagnosis. Five of the nine patients were autosomal dominant RP (56%), two (22%) were autosomal recessive RP, and two (22%) were X-linked RP. Nine of the 16 patients (56%) had probably positive or positive results. CONCLUSION: The Next Generation Sequencing used in this study allowed the molecular diagnosis to be confirmed in 56% of the patients and clarified the inheritance pattern of the patient's retinal dystrophies.

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INTRODUCTION: Retinal dystrophies (RDs) are the most common cause of inherited blindness and one of the most genetically heterogeneous human diseases. RDs arise from mutations in genes involved in development and function of photoreceptors or other retinal cells. Identification of the genetic defect causing RD allows accurate diagnosis, prognosis, and counseling in affected patients. Molecular diagnosis is a tremendous challenge in RDs due to their locus and phenotypic heterogeneity. As conventional DNA sequencing approaches are impractical in such situation, Next Generation Sequencing (NGS)-based protocols are needed to identify RD-causing mutations. This is being accomplished by sequencing RD gene panels or by whole exome or whole genome sequencing approaches. Areas covered: This review discusses the current strategies for molecular diagnosis in RDs including their advantages and limitations, as well as their utility in diagnosis of non-syndromic versus syndromic RDs. Results of ongoing gene therapy protocols in RDs are also presented. Expert commentary: Molecular diagnosis in RD improves the medical management of patients. Importantly, demand for molecular screening for RDs is greatly expanding not only as a result of increasing development and availability of NGS technologies, but also of the growing number of gene-based clinical trials offering a potential treatment to patients.

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ABSTRACT Purpose: To analyze the clinical features, visual acuity, and full-field electroretinogram (ERG) findings of 15 patients with the neuronal ceroid lipofuscinosis (NCL) phenotype and to establish the role of ERG testing in NCL diagnosis. Methods: The medical records of five patients with infantile NCL, five with Jansky-Bielschowsky disease, and five with juvenile NCL who underwent full-field ERG testing were retrospectively analyzed. Results: Progressive vision loss was the initial symptom in 66.7% of patients and was isolated or associated with ataxia, epilepsy, and neurodevelopmental involution. Epilepsy was present in 93.3% of patients, of whom 86.6% presented with neurodevelopmental involution. Fundus findings ranged from normal to pigmentary/atrophic abnormalities. Cone-rod, rod-cone, and both types of dysfunction were observed in six, one, and eight patients, respectively. Conclusion: In our study, all patients with the NCL phenotype had abnormal ERG findings, and the majority exhibited both cone-rod and rod-cone dysfunction. We conclude that ERG is a valuable tool for the characterization of visual dysfunction in patients with the NCL phenotype and is useful for diagnosis.

RESUMO Objetivo: Analisar o quadro clínico, a acuidade visual e o eletrorretinograma de campo total (ERG) de 15 pacientes com o fenótipo da lipofuscinose ceróide neuronal (LCN), estabelecendo o papel do eletrorretinograma no seu diagnóstico. Métodos: Eletrorretinograma foi realizado em 5 pacientes com lipofuscinose ceróide neuronal infantil, 5 com doença de Jansky-Bielschowsky e 5 com lipofuscinose ceróide neuronal juvenil sendo feita uma análise retrospectiva dos registros médicos. Resultados: A perda progressiva da acuidade visual foi o sintoma inicial em 66,7%; isolada ou associada à ataxia, epilepsia e involução do desenvolvimento neuropsico motor. Epilepsia foi o sintoma inicial em 93,3% e 86,6% apresentaram involução do desenvolvimento neuropsicomotor. Achados fundoscópicos variaram de normal a alterações pigmentares/atróficas. Disfunção de cone-bastonete foi constatada em 6 pacientes, bastonete-cone em 1 e em 8 pacientes observou-se disfunção proporcional de ambos os sistemas. Conclusão: O eletrorretinograma foi alterado em todos os pacientes, e o achado mais frequente foi o comprometimento de cones e bastonetes. O eletrorretinograma constitui, portanto, uma ferramenta valiosa para caracterizar a disfunção visual em pacientes com o fenótipo da lipofuscinose ceróide neuronal, contribuindo para seu diagnóstico.

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BACKGROUND: Although the pathogenicity of the prominin-1 (PROM1) gene has already been described as associated with autosomal dominant Stargardt disease, little is known about sequence variations in this gene. PURPOSE: The aim of this study was to evaluate PROM1 gene sequence variations in patients with macular dystrophy. MATERIAL AND METHODS: This retrospective study evaluated variations in the PROM1 gene detected by next-generation sequencing test in patients with macular dystrophy and Stargardt disease. RESULTS: Of 25 medical records of patients with Stargardt disease, three records of patients with PROM1 gene sequence variations were selected for the study. The p.Asp776Val and p.Asp829Asn variants were detected in cases 1 and 2, respectively, and predicted to be pathogenic; they were probably responsible for macular dystrophy in these patients. Case 3 showed a p.Ala643Gly variant in the PROM1 gene and a single variation in the ABCA4 gene, but molecular testing results were inconclusive. CONCLUSIONS: In cases of Stargardt disease, where molecular testing results are inconclusive for pathogenic variations in the ABCA4 gene, variations in the PROM1 gene may occur and be considered responsible for the disease in the molecular analysis. This study described three cases in which variations in PROM1 gene may play a role in the pathogenesis of macular dystrophy or be associated with both autosomal recessive and autosomal dominant inheritance.

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ABSTRACT Purpose: The aim of the present study was to use enhanced depth imaging optical coherence tomography (EDI-OCT) to investigate choroidal changes in patients with cone dystrophy (CD) and to correlate these findings with clinical and electroretinography (ERG) findings. Methods: This case-control study included 40 eyes of 20 patients with CD and 40 eyes of 40 age- and refraction-matched healthy individuals. Choroidal thickness (CT) measurements were obtained under the foveal center and at 500 and 1,500 μm from the nasal and temporal regions to the center of the fovea, respectively. EDI-OCT and ERG data were analyzed, and the correlations of CT with the best-corrected visual acuity (BCVA) and the central foveal thickness (CFT) were evaluated. Results: The mean subfoveal CTs in the CD and control groups were 240.70 ± 70.78 and 356.18 ± 48.55 μm, respectively. The subfoveal CT was significantly thinner in patients with CD than in the controls (p<0.001). The patients with CD also had significantly thinner choroids than the controls at each measurement location relative to the fovea (p<0.001). The subfoveal CT in the CD group correlated with CFT (p=0.012), but no significant correlation was found between the subfoveal CT and BCVA or photopic ERG responses. Conclusions: The present study demonstrated a significant thinning of the choroid in patients with CD. EDI-OCT is a useful technique for describing the choroidal changes occurring in CD. Future studies investigating the association between choroidal changes and outer retinal destruction or the disease stage may provide a better understanding of the pathophysiology of CD.

RESUMO Objetivo: O objetivo deste estudo foi a utilização de imagens de tomografia de coerência óptica com profundidade aprimorada (EDI-OCT) para investigar alterações da coroide em pacientes com distrofia de cones (CD) e correlacionar esses achados com os achados clínicos e de eletrorretinografia (ERG). Métodos: Este estudo de caso-controle incluiu 40 olhos de 20 pacientes com CD e 40 olhos de 40 indivíduos saudáveis com idades e refração pareados. As medidas da espessura da coroide (CT) foram obtidas sob o centro foveal e a 500 μm e 1.500 μm de distância do centro da fóvea, nas regiões nasais e temporais. Dados de EDI-OCT e ERG foram analisados e as correlações do CT com a acuidade visual melhor corrigida (BCVA) e da espessura foveal central (CFT) foram realizadas. Resultados: As CTs subfoveais médias nos grupos CD e controle foram 240,70 ± 70,78 μm e 356,18 ± 48,55 μm, respectivamente. A CT subfoveal foi significativamente mais fina em pacientes com CD do que nos controles (p<0,001). Os com CD pacientes apresentaram também coroides significativamente mais finas do que os controles, em cada local de medição em relação à fóvea (p<0,001). A CT subfoveal no grupo CD se correlacionou com o CFT (p=0,012), mas nenhuma correlação significativa foi encontrada entre a CT subfoveal e a acuidade visual ou respostas fotópicas da ERG. Conclusões: O presente estudo demonstrou um afinamento significativo da coroide em pacientes com CD. A EDI-OCT é uma técnica útil para descrever as mudanças que ocorrem na coroide de pacientes com CD. Futuros estudos investigando a associação entre as alterações da coroide e a destruição da retina externa ou estágio da doença irão proporcionar uma melhor compreensão da fisiopatologia da CD.

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Inherited retinal diseases are uncommon pathologies and one of the most harmful causes of childhood and adult blindness. Leber congenital amaurosis (LCA) is the most severe kind of these diseases accounting for approximately 5% of the whole retinal dystrophies and 20% of the children that study on blind schools. Clinical ophthalmologic findings including severe vision loss, nystagmus and ERG abnormalities should be suspected through the first year of life in this group of patients. Phenotypic variability is found when LCA patients have a full ophthalmologic examination. However, a correct diagnosis may be carried out; the determination of ophthalmologic clues as light sensibility, night blindness, fundus pigmentation, among other, join with electroretinographics findings, optical coherence tomography, and new technologies as molecular gene testing may help to reach to a precise diagnosis. Several retinal clinical features in LCA may suggest a genetic or gene particular defect; thus genetic-molecular tools could directly corroborate the clinical diagnosis. Currently, approximately 20 genes have been associated to LCA. In this review, historical perspective, clinical ophthalmological findings, new molecular-genetics technologies, possible phenotype-genotypes correlations, and gene therapy for some LCA genes are described.