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1.
Arch. Soc. Esp. Oftalmol ; 99(5): 205-208, May. 2024. tab, ilus
Article Es | IBECS | ID: ibc-VR-71

El síndrome de Bardet-Biedl (SBB) es una ciliopatía que se asocia principalmente a distrofia retiniana, disfunción renal, polidactilia posaxial, obesidad, déficit cognitivo e hipogonadismo. Los síntomas vinculados a la distrofia retiniana no suelen aparecer hasta la primera década de vida, por lo que la detección tiende a retrasarse. La afectación ocular puede ser la forma inicial de manifestación de este síndrome, incluso puede ser la única, por lo que se debería tener en cuenta en el diagnóstico diferencial de una ambliopía en un niño que no mejora a pesar del correcto cumplimiento del tratamiento. Se presenta un caso de baja agudeza visual (AV) en una paciente pediátrica como manifestación inicial que lleva al diagnóstico del SBB y que es, además, el único síntoma que exhibe hasta la fecha, a pesar de tratarse de una enfermedad multisistémica.(AU)


Bardet–Biedl syndrome is a ciliopathy mainly associated with retinal dystrophy, renal dysfunction, post-axial polydactyly, obesity, cognitive deficit and hypogonadism. The symptoms associated with retinal dystrophy do not usually appear until the first decade of life, so the diagnosis is usually delayed. Ocular involvement may be the initial form of manifestation of this syndrome, it may even be the only one, so it should be taken into account in the differential diagnosis of amblyopia in a child who does not improve despite correct compliance with treatment. A case of low visual acuity in a pediatric patient is presented as an initial manifestation that leads to the diagnosis of Bardet–Biedl syndrome, and which is also the only symptom that the patient presents to date, despite being a multisystem disease.(AU)


Humans , Female , Bardet-Biedl Syndrome , Eye Diseases , Vision, Ocular , Macular Degeneration , Amblyopia , Retinal Dystrophies , Inpatients , Physical Examination , Ophthalmology
2.
Invest Ophthalmol Vis Sci ; 65(5): 22, 2024 May 01.
Article En | MEDLINE | ID: mdl-38743414

Purpose: To describe the clinical, electrophysiological and genetic spectrum of inherited retinal diseases associated with variants in the PRPH2 gene. Methods: A total of 241 patients from 168 families across 15 sites in 9 countries with pathogenic or likely pathogenic variants in PRPH2 were included. Records were reviewed for age at symptom onset, visual acuity, full-field ERG, fundus colour photography, fundus autofluorescence (FAF), and SD-OCT. Images were graded into six phenotypes. Statistical analyses were performed to determine genotype-phenotype correlations. Results: The median age at symptom onset was 40 years (range, 4-78 years). FAF phenotypes included normal (5%), butterfly pattern dystrophy, or vitelliform macular dystrophy (11%), central areolar choroidal dystrophy (28%), pseudo-Stargardt pattern dystrophy (41%), and retinitis pigmentosa (25%). Symptom onset was earlier in retinitis pigmentosa as compared with pseudo-Stargardt pattern dystrophy (34 vs 44 years; P = 0.004). The median visual acuity was 0.18 logMAR (interquartile range, 0-0.54 logMAR) and 0.18 logMAR (interquartile range 0-0.42 logMAR) in the right and left eyes, respectively. ERG showed a significantly reduced amplitude across all components (P < 0.001) and a peak time delay in the light-adapted 30-Hz flicker and single-flash b-wave (P < 0.001). Twenty-two variants were novel. The central areolar choroidal dystrophy phenotype was associated with 13 missense variants. The remaining variants showed marked phenotypic variability. Conclusions: We described six distinct FAF phenotypes associated with variants in the PRPH2 gene. One FAF phenotype may have multiple ERG phenotypes, demonstrating a discordance between structure and function. Given the vast spectrum of PRPH2 disease our findings are useful for future clinical trials.


Electroretinography , Peripherins , Phenotype , Retinal Dystrophies , Visual Acuity , Humans , Peripherins/genetics , Middle Aged , Adult , Male , Female , Adolescent , Retinal Dystrophies/genetics , Retinal Dystrophies/physiopathology , Retinal Dystrophies/diagnosis , Aged , Visual Acuity/physiology , Child , Young Adult , Child, Preschool , Tomography, Optical Coherence , Mutation , Fluorescein Angiography , Genetic Association Studies , Retrospective Studies , DNA Mutational Analysis , DNA/genetics , Pedigree
3.
Med J Malaysia ; 79(3): 342-347, 2024 May.
Article En | MEDLINE | ID: mdl-38817069

INTRODUCTION: Inherited retinal dystrophy (IRD) is a group of untreated genetic ocular diseases that mostly affect young people. The number of patients with IRD worldwide, including in developing countries, is growing each year. This literature review aimed to investigate the current utilised genetic screening of IRD worldwide and to propose the most feasible genetics test and diagnostic method for IRD in developing countries, especially Indonesia. MATERIALS AND METHODS: A literature search was performed in PubMed and Google Scholar databases. Papers conducting wide genome sequencing, including panel sequencing (panel-seq), microarray, whole exome sequencing (WES), whole genome sequencing (WGS) and Sanger sequencing on patients with IRD, were included. Papers were sorted into several groups to visualise the sequencing technology's detection rate. Detection rate comparison analysis was done using the meta-regress protocol in the R program. Whereas the number of novel mutations in each testing tool each year was pooled and compared in the graph. RESULTS: After conducting the literature study, 37 papers were sorted from 451 results. Most studies conducted a panel-seq with 16 records followed by WES with seven records. The detection rate of the WES meta-analysis was 0.66, which was slightly better than the panel-seq with 0.55. The number of novel mutation discoveries fluctuated each year with panel-seq as the most prominent finder. Cost factors and the limitation of sequencing devices make panel-seq a more appropriate tool in Indonesia. CONCLUSION: The most effective selection for evaluated genetic testing was WES. Therefore, panel-seq is more suitable for first-tier genetic testing in Indonesia.


Developing Countries , Genetic Testing , Retinal Dystrophies , Humans , Indonesia , Genetic Testing/methods , Retinal Dystrophies/genetics , Retinal Dystrophies/diagnosis
5.
JCI Insight ; 9(8)2024 Apr 22.
Article En | MEDLINE | ID: mdl-38646933

Inherited retinal dystrophies (IRDs) are progressive diseases leading to vision loss. Mutation in the eyes shut homolog (EYS) gene is one of the most frequent causes of IRD. However, the mechanism of photoreceptor cell degeneration by mutant EYS has not been fully elucidated. Here, we generated retinal organoids from induced pluripotent stem cells (iPSCs) derived from patients with EYS-associated retinal dystrophy (EYS-RD). In photoreceptor cells of RD organoids, both EYS and G protein-coupled receptor kinase 7 (GRK7), one of the proteins handling phototoxicity, were not in the outer segment, where they are physiologically present. Furthermore, photoreceptor cells in RD organoids were vulnerable to light stimuli, and especially to blue light. Mislocalization of GRK7, which was also observed in eys-knockout zebrafish, was reversed by delivering control EYS into photoreceptor cells of RD organoids. These findings suggest that avoiding phototoxicity would be a potential therapeutic approach for EYS-RD.


Induced Pluripotent Stem Cells , Organoids , Retinal Dystrophies , Zebrafish , Animals , Humans , Eye Proteins/genetics , Eye Proteins/metabolism , Induced Pluripotent Stem Cells/metabolism , Light/adverse effects , Mutation , Organoids/metabolism , Retina/metabolism , Retina/pathology , Retinal Dystrophies/therapy , Retinal Dystrophies/genetics , Retinal Dystrophies/metabolism
6.
Mol Biol Rep ; 51(1): 590, 2024 Apr 29.
Article En | MEDLINE | ID: mdl-38683245

BACKGROUND: Boucher Neuhäuser Syndrome (BNS) is a rare disease with autosomal recessive inheritance defined by the classical triad; early-onset ataxia, hypogonadism and chorioretinal dystrophy. CASE PRESENTATION: We present two siblings diagnosed with BNS at midlife, identified with homozygous state of a novel PNPLA6 missense mutation. One healthy sibling and the mother were heterozygous carriers of the mutation. The proband presented with the classical triad and the other sibling presented with visual problems at first. The proband was referred to our department by a private Neurologist, in early adulthood, because of hypogonadism, cerebellar ataxia, axonal neuropathy, and chorioretinal dystrophy for further evaluation. The sibling was referred to our department for evaluation, at childhood, due to visual problems. Later, the patient displayed the triad of ataxia, hypogonadotropic hypogonadism, and chorioretinal dystrophy. The unusual medical history of the two siblings led to further examinations and eventually the diagnosis of the first BNS cases in Cyprus. WES-based ataxia in silico gene panel analysis revealed 15 genetic variants and further filtering analysis revealed the PNPLA6 c.3323G > A variant. Segregation analysis in the family with Sanger sequencing confirmed the PNPLA6 homozygous variant c.3323G > A, p.Arg1108Gln in exon 29. CONCLUSIONS: This highlights the importance of considering rare inherited causes of visual loss, spinocerebellar ataxia, or/and HH in a neurology clinic and the significant role of genetic sequencing in the diagnostic process.


Acyltransferases , Cerebellar Ataxia , Hypogonadism , Retinal Dystrophies , Adult , Female , Humans , Male , Middle Aged , Acyltransferases/genetics , Cerebellar Ataxia/genetics , Hypogonadism/genetics , Mutation, Missense/genetics , Pedigree , Phospholipases/genetics , Retinal Dystrophies/genetics , Siblings , Spinocerebellar Ataxias/genetics
7.
Invest Ophthalmol Vis Sci ; 65(3): 9, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-38466282

Purpose: RDH12 is among the most common genes found in individuals with early-onset severe retinal (EOSRD). Adaptive optics scanning light ophthalmoscopy (AOSLO) enables resolution of individual rod and cone photoreceptors in the retina. This study presents the first AOSLO imaging of individuals with RDH12-associated EOSRD. Methods: Case series of patients who attended Moorfields Eye Hospital (London, UK). Spectral-domain optical coherence tomography, near-infrared reflectance (NIR), and blue autofluorescence imaging were analyzed. En face image sequences of photoreceptors were recorded using either of two AOSLO modalities. Cross-sectional analysis was undertaken for seven patients and longitudinal analysis for one patient. Results: Nine eyes from eight patients are presented in this case series. The mean age at the time of the assessment was 11.2 ± 6.5 years of age (range 7-29). A subfoveal continuous ellipsoid zone (EZ) line was present in eight eyes. Posterior pole AOSLO revealed patches of cone mosaics. Average cone densities at regions of interest 0.5° to the fovea ranged from 12,620 to 23,660 cells/mm2, whereas intercell spacing ranged from 7.0 to 9.7 µm. Conclusions: This study demonstrates that AOSLO can provide useful high-quality images in patients with EOSRD, even during childhood, with nystagmus, and early macular atrophy. Cones at the posterior pole can appear as scattered islands or, possibly later in life, as a single subfoveal conglomerate. Detailed image analysis suggests that retinal pigment epithelial stress and dysfunction may be the initial step toward degeneration, with NIR being a useful tool to assess retinal well-being in RDH12-associated EOSRD.


Eye Diseases, Hereditary , Retina , Retinal Dystrophies , Humans , Child , Adolescent , Young Adult , Adult , Cross-Sectional Studies , Retina/diagnostic imaging , Retinal Dystrophies/diagnostic imaging , Retinal Dystrophies/genetics , Tomography, Optical Coherence , Alcohol Oxidoreductases/genetics
9.
Klin Monbl Augenheilkd ; 241(3): 259-265, 2024 Mar.
Article En | MEDLINE | ID: mdl-38508214

Retinal dystrophies linked to the RPE65 gene are mostly fast-progressing retinal diseases, with childhood onset of night blindness and progressive visual loss up to the middle adult age. Rare phenotypes linked to this gene are known with congenital stationary night blindness or slowly progressing retinitis pigmentosa, as well as an autosomal dominant c.1430A>G (p.Asp477Gly) variant. This review gives an overview of the current knowledge of the clinical phenotypes, as well as experience with the efficacy and safety of the approved gene augmentation therapy voretigene neparvovec.


Night Blindness , Retinal Dystrophies , Retinitis Pigmentosa , Adult , Child , Humans , cis-trans-Isomerases/genetics , Genetic Therapy , Mutation , Night Blindness/therapy , Phenotype , Retinal Dystrophies/diagnosis , Retinal Dystrophies/genetics , Retinal Dystrophies/therapy , Retinitis Pigmentosa/diagnosis , Retinitis Pigmentosa/genetics , Retinitis Pigmentosa/therapy
10.
Proc Natl Acad Sci U S A ; 121(11): e2316118121, 2024 Mar 12.
Article En | MEDLINE | ID: mdl-38442152

Retinitis pigmentosa (RP) is a common form of retinal dystrophy that can be caused by mutations in any one of dozens of rod photoreceptor genes. The genetic heterogeneity of RP represents a significant challenge for the development of effective therapies. Here, we present evidence for a potential gene-independent therapeutic strategy based on targeting Nr2e3, a transcription factor required for the normal differentiation of rod photoreceptors. Nr2e3 knockout results in hybrid rod photoreceptors that express the full complement of rod genes, but also a subset of cone genes. We show that germline deletion of Nr2e3 potently protects rods in three mechanistically diverse mouse models of retinal degeneration caused by bright-light exposure (light damage), structural deficiency (rhodopsin-deficient Rho-/- mice), or abnormal phototransduction (phosphodiesterase-deficient rd10 mice). Nr2e3 knockout confers strong neuroprotective effects on rods without adverse effects on their gene expression, structure, or function. Furthermore, in all three degeneration models, prolongation of rod survival by Nr2e3 knockout leads to lasting preservation of cone morphology and function. These findings raise the possibility that upregulation of one or more cone genes in Nr2e3-deficient rods may be responsible for the neuroprotective effects we observe.


Neuroprotective Agents , Retinal Dystrophies , Retinitis Pigmentosa , Animals , Mice , Retinal Cone Photoreceptor Cells , Retinitis Pigmentosa/genetics , Disease Models, Animal , Germ Cells , Orphan Nuclear Receptors
11.
Int J Mol Sci ; 25(5)2024 Mar 02.
Article En | MEDLINE | ID: mdl-38474159

PRPH2, one of the most frequently inherited retinal dystrophy (IRD)-causing genes, implies a high phenotypic variability. This study aims to analyze the PRPH2 mutational spectrum in one of the largest cohorts worldwide, and to describe novel pathogenic variants and genotype-phenotype correlations. A study of 220 patients from 103 families recruited from a database of 5000 families. A molecular diagnosis was performed using classical molecular approaches and next-generation sequencing. Common haplotypes were ascertained by analyzing single-nucleotide polymorphisms. We identified 56 variants, including 11 novel variants. Most of them were missense variants (64%) and were located in the D2-loop protein domain (77%). The most frequently occurring variants were p.Gly167Ser, p.Gly208Asp and p.Pro221_Cys222del. Haplotype analysis revealed a shared region in families carrying p.Leu41Pro or p.Pro221_Cys222del. Patients with retinitis pigmentosa presented an earlier disease onset. We describe the largest cohort of IRD families associated with PRPH2 from a single center. Most variants were located in the D2-loop domain, highlighting its importance in interacting with other proteins. Our work suggests a likely founder effect for the variants p.Leu41Pro and p.Pro221_Cys222del in our Spanish cohort. Phenotypes with a primary rod alteration presented more severe affectation. Finally, the high phenotypic variability in PRPH2 hinders the possibility of drawing genotype-phenotype correlations.


Retinal Dystrophies , Retinitis Pigmentosa , Humans , DNA Mutational Analysis , Mutation , Mutation, Missense , Phenotype , Retinal Dystrophies/genetics , Retinitis Pigmentosa/genetics
12.
Transl Vis Sci Technol ; 13(3): 9, 2024 Mar 01.
Article En | MEDLINE | ID: mdl-38477924

Purpose: The porcine retina represents an optimal model system to study treatment approaches for inherited retinal dystrophies owing to close anatomical similarities to the human retina, including a cone enriched visual streak. The aim of this work was to establish a protocol to keep explants in culture for up to 28 days with good morphological preservation. Methods: Two to four retina explants per eye were obtained from the central part of the retina and transferred onto a membrane insert with the photoreceptors facing down. Different medium compositions using Neurobasal-A medium containing 100 or 450 mg/dL glucose and combinations of fetal calf serum, B-27 with or without insulin and N-2 were tested. We developed a tissue quality score with robust markers for different retinal cell types (protein kinase C alpha, peanut agglutinin and 4',6-diamidino-2-phenylindol). Results: Retinae were kept until 28 days with only little degradation. The best results were attained using Neurobasal-A medium containing 100 mg/dL glucose supplemented with B-27 containing insulin and N-2. For an easy preparation process, it is necessary to minimize transport time and keep the eyes on ice until dissected. Heat-mediated decontamination by the butcher has to be avoided. Conclusions: Using a standardized protocol, porcine retina explants represent an easy to handle intermediate model between in vitro and in vivo experimentation. This model system is robustly reproducible and contributes to the implementation of the 3R principle to minimize animal experimentation. Translational Relevance: This model can be used to test future therapeutic approaches for inherited retinal dystrophies.


Retina , Retinal Dystrophies , Humans , Swine , Animals , Retinal Cone Photoreceptor Cells , Research Design , Glucose
13.
Invest Ophthalmol Vis Sci ; 65(3): 11, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-38466290

Purpose: The purpose of this study was to investigate the genotypic and phenotypic characteristics of CRB1-associated early onset retinal dystrophy (CRB1-eoRD) and retinal architecture by swept-source optical coherence tomography (SS-OCT). Methods: Eleven probands with CRB1-eoRD were recruited. Clinical information, genetic analysis, and comprehensive ophthalmic examinations including SS-OCT and SS-OCT angiography (SS-OCTA) were conducted. Results: A total of 81.8% (9/11) of CRB1-eoRD presented as Leber congenital amaurosis (LCA). Common clinical manifestations included coin-like yellow-white retinal spots (20/22, 90.9%) and para-arteriolar retinal pigment epithelial retention (12/22, 54.5%). Nineteen different CRB1 variants were detected in our case series, including 12 missense, 3 frameshifts, 3 nonsense, and 1 splicing. Of them, 12 variants had been reported, and 7 were novel. SS-OCT showed thinner central macula (the LCA group, P < 0.0001), thicker total retina (P < 0.0001), thinner outer retina (P < 0.05), and thicker inner retina (P < 0.0001) compared with the healthy control. The inner/outer (I/O) retina thickness ratio of CRB1-eoRD was 3.0, higher than the healthy control of 1.2 and other inherited retinal diseases (IRDs) of 2.2 (P < 0.0001 and P = 0.0027, respectively). SS-OCTA revealed an increased vascular density and perfusion area of the superficial vascular complex and deep vascular complex in CRB1-eoRD. Conclusions: LCA emerges as a frequently occurring phenotype in CRB1-eoRD. The unique features of SS-OCT and SS-OCTA are illustrated, and the novel biomarker, I/O ratio, may facilitate early diagnosis. The insights gained from this study hold significant value in determining the treatment window for potential forthcoming CRB1 gene therapy.


Leber Congenital Amaurosis , Retinal Dystrophies , Humans , Retina/diagnostic imaging , Retinal Dystrophies/diagnosis , Retinal Dystrophies/genetics , Leber Congenital Amaurosis/diagnosis , Leber Congenital Amaurosis/genetics , Genotype , Phenotype , Eye Proteins/genetics , Membrane Proteins/genetics , Nerve Tissue Proteins/genetics
15.
Invest Ophthalmol Vis Sci ; 65(2): 9, 2024 Feb 01.
Article En | MEDLINE | ID: mdl-38315492

Purpose: This observational study aimed to identify mutations in monogenic syndromic high myopia (msHM) using data from reported samples (n = 9370) of the Myopia Associated Genetics and Intervention Consortium (MAGIC) project. Methods: The targeted panel containing 298 msHM-related genes was constructed and screening of clinically actionable variants was performed based on whole exome sequencing. Capillary sequencing was used to verify the identified gene mutations in the probands and perform segregation analysis with their relatives. Results: A total of 381 candidate variants in 84 genes and 85 eye diseases were found to contribute to msHM in 3.6% (335/9370) of patients with HM. Among them, the 22 genes with the most variations accounted for 62.7% of the diagnostic cases. In the genotype-phenotype association analysis, 60% (201/335) of suspected msHM cases were recalled and 25 patients (12.4%) received a definitive genetic diagnosis. Pathogenic variants were distributed in 18 msHM-related diseases, mainly involving retinal dystrophy genes (e.g. TRPM1, CACNA1F, and FZD4), connective tissue disease genes (e.g. FBN1 and COL2A1), corneal or lens development genes (HSF4, GJA8, and MIP), and other genes (TEK). The msHM gene mutation types were allocated to four categories: nonsense mutations (36%), missense mutations (36%), frameshift mutations (20%), and splice site mutations (8%). Conclusions: This study highlights the importance of thorough molecular subtyping of msHM to provide appropriate genetic counselling and multispecialty care for children and adolescents with HM.


Myopia , Retinal Dystrophies , TRPM Cation Channels , Child , Adolescent , Humans , Exome Sequencing , Mutation , Myopia/diagnosis , Myopia/genetics , Frameshift Mutation , Retinal Dystrophies/genetics , Pedigree , Frizzled Receptors/genetics , TRPM Cation Channels/genetics
16.
BMC Ophthalmol ; 24(1): 55, 2024 Feb 05.
Article En | MEDLINE | ID: mdl-38317096

BACKGROUND: Inherited retinal degenerations (IRDs) are a group of rare genetic conditions affecting retina of the eye that range in prevalence from 1 in 2000 to 1 in 4000 people globally. This review is based on a retrospective analysis of research articles reporting IRDs associated genetic findings in Pakistani families between 1999 and April 2023. METHODS: Articles were retrieved through survey of online sources, notably, PubMed, Google Scholar, and Web of Science. Following a stringent selection criterion, a total of 126 research articles and conference abstracts were considered. All reported variants were cross-checked and validated for their correct genomic nomenclature using different online resources/databases, and their pathogenicity scores were explained as per ACMG guidelines. RESULTS: A total of 277 unique sequence variants in 87 distinct genes, previously known to cause IRDs, were uncovered. In around 70% cases, parents of the index patient were consanguineously married, and approximately 88.81% of the detected variants were found in a homozygous state. Overall, more than 95% of the IRDs cases were recessively inherited. Missense variants were predominant (41.88%), followed by Indels/frameshift (26.35%), nonsense (19.13%), splice site (12.27%) and synonymous change (0.36%). Non-syndromic IRDs were significantly higher than syndromic IRDs (77.32% vs. 22.68%). Retinitis pigmentosa (RP) was the most frequently observed IRD followed by Leber's congenital amaurosis (LCA). Altogether, mutations in PDE6A gene was the leading cause of IRDs in Pakistani families followed by mutations in TULP1 gene. CONCLUSION: In summary, Pakistani families are notable in expressing recessively inherited monogenic disorders including IRDs likely due to the highest prevalence of consanguinity in the country that leads to expression of rare pathogenic variants in homozygous state.


Retinal Dystrophies , Retinitis Pigmentosa , Humans , Pakistan/epidemiology , Retrospective Studies , Retinal Dystrophies/epidemiology , Retinal Dystrophies/genetics , Retina/pathology , Retinitis Pigmentosa/genetics , Mutation , Pedigree , Eye Proteins/genetics , Cyclic Nucleotide Phosphodiesterases, Type 6/genetics
17.
BMC Ophthalmol ; 24(1): 60, 2024 Feb 12.
Article En | MEDLINE | ID: mdl-38347443

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.


Retinal Dystrophies , Retinitis Pigmentosa , Usher Syndromes , Humans , Mutation , Mexico/epidemiology , Retinal Dystrophies/epidemiology , Retinal Dystrophies/genetics , Retinitis Pigmentosa/genetics , Pedigree , ATP-Binding Cassette Transporters/genetics
18.
Hum Genet ; 143(2): 197-210, 2024 Feb.
Article En | MEDLINE | ID: mdl-38282009

The purpose of this study was to screen Copy Number Variations (CNVs) in 35 unsolved Inherited Retinal Dystrophy (IRD) families. Initially, next generation sequencing, including a specific Hereditary Eye Disease Enrichment Panel or Whole exome sequencing, was employed to screen (likely) pathogenic Single-nucleotide Variants (SNVs) and small Insertions and Deletions (indels) for these cases. All available SNVs and indels were further validated and co-segregation analyses were performed in available family members by Sanger sequencing. If not, after excluding deep intronic variants, Multiplex ligation-dependent probe amplification (MLPA), quantitative fluorescence PCR (QF-PCR) and Sanger sequencing were employed to screen CNVs. We determined that 18 probands who had heterozygous SNVs/indels or whose parents were not consanguineous but had homozygous SNVs/indels in autosomal recessive IRDs genes had CNVs in another allele of these genes, 11 families had disease-causing hemizygous CNVs in X-linked IRD genes, 6 families had (likely) pathogenic heterozygous CNVs in PRPF31 gene. Of 35 families, 33 different CNVs in 16 IRD-associated genes were detected, with PRPF31, EYS and USH2A the most common disease-causing gene in CNVs. Twenty-six and 7 of them were deletion and duplication CNVs, respectively. Among them, 14 CNVs were first reported in this study. Our research indicates that CNVs contribute a lot to IRDs, and screening of CNVs substantially increases the diagnostic rate of IRD. Our results emphasize that MLPA and QF-PCR are ideal methods to validate CNVs, and the novel CNVs reported herein expand the mutational spectrums of IRDs.


Retinal Dystrophies , Usher Syndromes , Humans , DNA Copy Number Variations , Mutation , Heterozygote , Eye Proteins/genetics
19.
Sci Rep ; 14(1): 2019, 2024 01 23.
Article En | MEDLINE | ID: mdl-38263197

Photoreceptor cell death, primarily through apoptosis, related to retinal disorders like retinitis pigmentosa (RP), would result in vision loss. The pathological processes and crucial mutant conditions preceding photoreceptor cell demise are not well understood. This study aims to conduct an in-depth examination of early-stage changes in the widely utilized Pde6brd1/rd1 (rd1) mouse model, which has Pde6b gene mutations representing autosomal recessive RP disorder. We investigated the morphology and ultrastructure of retinal cells, including second-order neurons, during the initial phase of disease progression. Our findings revealed that mitochondrial alterations in rod photoreceptors were present as a predeath mutant state as early as postnatal day 3 (P3). The bipolar and horizontal cells from the rd1 mouse retina exhibited significant morphological changes in response to loss of photoreceptor cells, indicating that second-order neurons rely on these cells for their structures. Subsequent oral administration of idebenone, a mitochondria-protective agent, enhanced retinal function and promoted both photoreceptor cell survival and inner retinal second-order synaptogenesis in rd1 mice at P14. Our findings offer a mechanistic framework, suggesting that mitochondrial damage acts as an early driver for photoreceptor cell death in retinal degeneration.


Retinal Dystrophies , Retinitis Pigmentosa , Animals , Mice , Ubiquinone , Retina , Disease Models, Animal , Retinal Rod Photoreceptor Cells
20.
Ophthalmology ; 131(2): 161-178, 2024 Feb.
Article En | MEDLINE | ID: mdl-37704110

PURPOSE: To assess the impact of baseline data on psychophysical and morphological outcomes of subretinal voretigene neparvovec (VN) (Luxturna, Spark Therapeutics, Inc.) treatment. DESIGN: Single-center, retrospective, longitudinal, consecutive case series. PARTICIPANTS: Patients with RPE65-biallelic mutation-associated inherited retinal degeneration (RPE65-IRD) treated between February 2020 and March 2022 with VN and oral immunosuppression according to the manufacturer's recommendation by one surgeon (F.G.H.). METHODS: Retrospective analysis of surgical and clinical records, ancillary testing, and retinal imaging after VN therapy for RPE65-IRD. Descriptive statistics compared data at baseline up to 32 months post-treatment. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), low-luminance VA (LLVA), Goldmann visual fields (GVFs), chromatic full-field stimulus threshold (FST) testing (FST), scotopic and photopic 2-color threshold perimetry (2CTP), and multimodal retinal imaging. RESULTS: Thirty eyes of 19 patients were analyzed (10 pediatric patients < 20 years; 20 adult patients > 20 years of age; overall range: 8-40 years) with a median follow-up of 15 months (range, 1-32). The fovea was completely or partially detached in 16 eyes, attached in 12 eyes, and not assessable in 2 eyes on intraoperative imaging. Median BCVA at baseline was better in the pediatric group (P < 0.05) and did not change significantly independent of age. Meaningful loss of BCVA (≥ 0.3 logarithm of the minimal angle of resolution [logMAR]) occurred in 5 of 18 adult eyes, and a meaningful gain (≥-0.3 logMAR) occurred in 2 of 18 adult and 2 of 8 pediatric eyes. The LLVA and scotopic 2CTP improved considerably in pediatric patients. Scotopic blue FST improved at all ages but more in pediatric patients (8/8 eyes gained ≥ 10 decibels [dB]; P < 0.05). In pediatric patients, median GVF improved by 20% for target V4e and by 50% for target III4e (target I4e not detected). Novel atrophy developed in 13 of 26 eyes at the site of the bleb or peripheral of vascular arcades. Improvements in FST did not correlate with development of chorioretinal atrophy at 12 months. Mean central retinal thickness was 165.87 µm (± 26.26) at baseline (30 eyes) and 157.69 µm (± 30.3) at 12 months (26 eyes). Eight adult patients were treated unilaterally. The untreated eyes did not show meaningful changes during follow-up. CONCLUSIONS: These data in a clinical setting show the effectiveness of VN therapy with stable median BCVA and mean retinal thickness and improvements of LLVA, FST, and 2CTP up to 32 months. Treatment effects were superior in the pediatric group. We observed new chorioretinal atrophy in 50% of the treated eyes. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Retina , Retinal Dystrophies , Adult , Humans , Child , Retrospective Studies , Retinal Dystrophies/diagnosis , Retinal Dystrophies/genetics , Retinal Dystrophies/therapy , Mutation , Atrophy
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