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PURPOSE: Progressive inherited retinal degenerations (IRDs) affecting rods and cones are clinically and genetically heterogeneous and can lead to blindness with limited therapeutic options. The major gene defects have been identified in subjects of European and Asian descent with only few reports of North African descent. METHODS: Genome, targeted next-generation, and Sanger sequencing was applied to cohort of â¼4000 IRDs cases. Expression analyses were performed including Chip-seq database analyses, on human-derived retinal organoids (ROs), retinal pigment epithelium cells, and zebrafish. Variants' pathogenicity was accessed using 3D-modeling and/or ROs. RESULTS: Here, we identified a novel gene defect with three distinct pathogenic variants in UBAP1L in 4 independent autosomal recessive IRD cases from Tunisia. UBAP1L is expressed in the retinal pigment epithelium and retina, specifically in rods and cones, in line with the phenotype. It encodes Ubiquitin-associated protein 1-like, containing a solenoid of overlapping ubiquitin-associated domain, predicted to interact with ubiquitin. In silico and in vitro studies, including 3D-modeling and ROs revealed that the solenoid of overlapping ubiquitin-associated domain is truncated and thus ubiquitin binding most likely abolished secondary to all variants identified herein. CONCLUSION: Biallelic UBAP1L variants are a novel cause of IRDs, most likely enriched in the North African population.
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Distrofias de Cones e Bastonetes , Linhagem , Peixe-Zebra , Humanos , Distrofias de Cones e Bastonetes/genética , Distrofias de Cones e Bastonetes/patologia , Masculino , Feminino , Peixe-Zebra/genética , Animais , Genes Recessivos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Mutação/genética , Células Fotorreceptoras Retinianas Cones/patologia , Células Fotorreceptoras Retinianas Cones/metabolismo , Retina/patologia , Retina/metabolismo , Adulto , Tunísia , Retinose Pigmentar/genética , Retinose Pigmentar/patologia , Fenótipo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologiaRESUMO
Usher syndrome (USH) is the most common cause of deafblindness. USH is autosomal recessively inherited and characterized by rod-cone dystrophy or retinitis pigmentosa (RP), often accompanied by sensorineural hearing loss. Variants in >15 genes have been identified as causative for clinically and genetically distinct subtypes. Among the ultra-rare and recently discovered genes is ARSG, coding for the lysosomal sulfatase Arylsulfatase G. This subtype was assigned as "USH IV" with a late onset of RP and usually late-onset progressive SNHL without vestibular involvement. Here, we describe nine new subjects and the clinical description of four cases with the USH IV phenotype bearing seven novel and two known pathogenic variants. Functional experiments indicated the complete loss of sulfatase enzymatic activity upon ectopic expression of mutated ARSG cDNA. Interestingly, we identified a homozygous missense variant, p.(Arg99His), previously described in dogs with neuronal ceroid lipofuscinosis. Our study expands the genetic landscape of ARSG-USH IV and the number of known subjects by more than 30%. These findings highlight that USH IV likely has been underdiagnosed and emphasize the need to test molecularly unresolved subjects with deafblindness syndrome. Finally, testing of ARSG should be considered for the genetic work-up of apparent isolated inherited retinal diseases.
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INTRODUCTION: Infantile nystagmus and foveal hypoplasia associated with AHR gene defects is a newly recognized and rare disorder. Our aim was to present a patient with a novel biallelic AHR pathogenic variant with electrophysiological evidence of chiasmal misrouting. MATERIALS AND METHODS: Complete ocular examination, fundus imaging, visual evoked potentials (VEP) and full-field electroretinography were performed at initial presentation. Genetic testing was performed by whole exome sequencing. RESULTS: Female patient of 6 years old presented a reduced best corrected visual acuity, an infantile nystagmus and a grade III typical foveal hypoplasia without ocular hypopigmentation. A crossed asymmetry was discovered on pattern onset/offset VEP. Genetic testing put in evidence a novel homozygous variant in AHR: c.2242del, p. (Gln748Lysfs*5). During 11-years follow-up period, BCVA gradually improved. There was no evidence of retinal degeneration. CONCLUSION: AHR gene defects could be associated with infantile nystagmus, foveal hypoplasia and chiasmal misrouting.
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Eletrorretinografia , Potenciais Evocados Visuais , Fóvea Central , Nistagmo Congênito , Humanos , Feminino , Fóvea Central/anormalidades , Nistagmo Congênito/genética , Nistagmo Congênito/fisiopatologia , Nistagmo Congênito/diagnóstico , Criança , Receptores de Hidrocarboneto Arílico/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Acuidade Visual/fisiologia , Proteínas Repressoras/genética , Tomografia de Coerência ÓpticaRESUMO
BACKGROUND: Kabuki Syndrome is a rare and genetically heterogenous condition with both ophthalmic and systemic complications and typical facial features. We detail the macular phenotype in two unrelated patients with Kabuki syndrome due to de novo nonsense variants in KMT2D, one novel. A follow-up of 10 years is reported. Pathogenicity of both de novo nonsense variants is analyzed. METHODS: Four eyes of two young patients were studied by full clinical examination, kinetic perimetry, short wavelength autofluorescence, full field (ff) ERGs, and spectral-domain optical coherence tomography (SD-OCT). One patient had adaptive optic (AO) imaging. Whole exome sequencing was performed in both patients. RESULTS: Both patients had de novo nonsense variants in KMTD2. One patient had c.14843C>G; p. (Ser4948ter) novel variant and the second c.11119C>T; p. (Arg3707ter). Both had a stable Snellen visual acuity of 0.2-0.3. The retinal multimodal imaging demonstrated abnormalities at the fovea in both eyes: hyperreflectivity to blue light and a well-delimited gap-disruption of ellipsoid and interdigitation layer on OCT. The dark area on AO imaging is presumed to be absent for, or with structural change to photoreceptors. The ff ERGs and kinetic visual fields were normal. The foveal findings remained stable over several years. CONCLUSION: Kabuki syndrome-related maculopathy is a distinct loss of photoreceptors at the fovea as shown by multimodal imaging including, for the first time, AO imaging. This report adds to the literature of only one case with maculopathy with two additional macular dystrophies in patients with Kabuki syndrome. Although underestimated, these cases further raise awareness of the potential impact of retinal manifestations of Kabuki syndrome not only among ophthalmologists but also other healthcare professionals involved in the care of patients with this multisystem disorder.
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Anormalidades Múltiplas , Eletrorretinografia , Face , Angiofluoresceinografia , Doenças Hematológicas , Imagem Multimodal , Proteínas de Neoplasias , Fenótipo , Tomografia de Coerência Óptica , Doenças Vestibulares , Acuidade Visual , Humanos , Doenças Vestibulares/genética , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/fisiopatologia , Face/anormalidades , Doenças Hematológicas/genética , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/fisiopatologia , Tomografia de Coerência Óptica/métodos , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico , Seguimentos , Masculino , Feminino , Proteínas de Neoplasias/genética , Angiofluoresceinografia/métodos , Proteínas de Ligação a DNA/genética , Degeneração Macular/genética , Degeneração Macular/diagnóstico , Degeneração Macular/fisiopatologia , Pescoço , Fundo de Olho , DNA/genética , Sequenciamento do Exoma , Análise Mutacional de DNA , Macula Lutea/patologia , Fatores de Tempo , Adulto , AdolescenteRESUMO
Albinism is a genetically heterogeneous disease in which 21 genes are known so far. Its inheritance mode is autosomal recessive except for one X-linked form. The molecular analysis of exonic sequences of these genes allows for about a 70% diagnostic rate. About half (15%) of the unsolved cases are heterozygous for one pathogenic or probably pathogenic variant. Assuming that the missing variant may be located in non-coding regions, we performed sequencing for 122 such heterozygous patients of either the whole genome (27 patients) or our NGS panel (95 patients) that includes, in addition to all exons of the 21 genes, the introns and flanking sequences of five genes, TYR, OCA2, SLC45A2, GPR143 and HPS1. Rare variants (MAF < 0.01) in trans to the first variant were tested by RT-PCR and/or minigene assay. Of the 14 variants tested, nine caused either exon skipping or the inclusion of a pseudoexon, allowing for the diagnosis of 11 patients. This represents 9.8% (12/122) supplementary diagnosis for formerly unsolved patients and 75% (12/16) of those in whom the candidate variant was in trans to the first variant. Of note, one missense variant was demonstrated to cause skipping of the exon in which it is located, thus shedding new light on its pathogenic mechanism. Searching for non-coding variants and testing them for an effect on RNA splicing is warranted in order to increase the diagnostic rate.
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Albinismo , Éxons , Humanos , Éxons/genética , Albinismo/genética , Albinismo/diagnóstico , Feminino , Splicing de RNA , Masculino , Processamento Alternativo/genética , Mutação , Heterozigoto , Íntrons/genéticaRESUMO
PURPOSE: Dominant variants in the retinoic acid receptor beta (RARB) gene underlie a syndromic form of microphthalmia, known as MCOPS12, which is associated with other birth anomalies and global developmental delay with spasticity and/or dystonia. Here, we report 25 affected individuals with 17 novel pathogenic or likely pathogenic variants in RARB. This study aims to characterize the functional impact of these variants and describe the clinical spectrum of MCOPS12. METHODS: We used in vitro transcriptional assays and in silico structural analysis to assess the functional relevance of RARB variants in affecting the normal response to retinoids. RESULTS: We found that all RARB variants tested in our assays exhibited either a gain-of-function or a loss-of-function activity. Loss-of-function variants disrupted RARB function through a dominant-negative effect, possibly by disrupting ligand binding and/or coactivators' recruitment. By reviewing clinical data from 52 affected individuals, we found that disruption of RARB is associated with a more variable phenotype than initially suspected, with the absence in some individuals of cardinal features of MCOPS12, such as developmental eye anomaly or motor impairment. CONCLUSION: Our study indicates that pathogenic variants in RARB are functionally heterogeneous and associated with extensive clinical heterogeneity.
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Microftalmia , Receptores do Ácido Retinoico , Humanos , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , RetinoidesRESUMO
PURPOSE: To characterize the genotypic and phenotypic spectrum of foveal hypoplasia (FH). DESIGN: Multicenter, observational study. PARTICIPANTS: A total of 907 patients with a confirmed molecular diagnosis of albinism, PAX6, SLC38A8, FRMD7, AHR, or achromatopsia from 12 centers in 9 countries (n = 523) or extracted from publicly available datasets from previously reported literature (n = 384). METHODS: Individuals with a confirmed molecular diagnosis and availability of foveal OCT scans were identified from 12 centers or from the literature between January 2011 and March 2021. A genetic diagnosis was confirmed by sequence analysis. Grading of FH was derived from OCT scans. MAIN OUTCOME MEASURES: Grade of FH, presence or absence of photoreceptor specialization (PRS+ vs. PRS-), molecular diagnosis, and visual acuity (VA). RESULTS: The most common genetic etiology for typical FH in our cohort was albinism (67.5%), followed by PAX6 (21.8%), SLC38A8 (6.8%), and FRMD7 (3.5%) variants. AHR variants were rare (0.4%). Atypical FH was seen in 67.4% of achromatopsia cases. Atypical FH in achromatopsia had significantly worse VA than typical FH (P < 0.0001). There was a significant difference in the spectrum of FH grades based on the molecular diagnosis (chi-square = 60.4, P < 0.0001). All SLC38A8 cases were PRS- (P = 0.003), whereas all FRMD7 cases were PRS+ (P < 0.0001). Analysis of albinism subtypes revealed a significant difference in the grade of FH (chi-square = 31.4, P < 0.0001) and VA (P = 0.0003) between oculocutaneous albinism (OCA) compared with ocular albinism (OA) and Hermansky-Pudlak syndrome (HPS). Ocular albinism and HPS demonstrated higher grades of FH and worse VA than OCA. There was a significant difference (P < 0.0001) in VA between FRMD7 variants compared with other diagnoses associated with FH. CONCLUSIONS: We characterized the phenotypic and genotypic spectrum of FH. Atypical FH is associated with a worse prognosis than all other forms of FH. In typical FH, our data suggest that arrested retinal development occurs earlier in SLC38A8, OA, HPS, and AHR variants and later in FRMD7 variants. The defined time period of foveal developmental arrest for OCA and PAX6 variants seems to demonstrate more variability. Our findings provide mechanistic insight into disorders associated with FH and have significant prognostic and diagnostic value.
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Albinismo Ocular , Albinismo Oculocutâneo , Albinismo , Defeitos da Visão Cromática , Albinismo Ocular/diagnóstico , Albinismo Ocular/genética , Albinismo Oculocutâneo/diagnóstico , Albinismo Oculocutâneo/genética , Defeitos da Visão Cromática/diagnóstico , Defeitos da Visão Cromática/genética , Proteínas do Citoesqueleto , Fóvea Central/anormalidades , Humanos , Proteínas de Membrana , Transtornos da Visão/diagnósticoRESUMO
The above-ground part of the Salsola passerine was found to contain ~13% (w/w) of polysaccharides extractable with water and aqueous solutions of ammonium oxalate and sodium carbonate. The fractions extracted with aqueous sodium carbonate solutions had the highest yield. The polysaccharides of majority fractions are characterized by similar monosaccharide composition; namely, galacturonic acid and arabinose residues are the principal components of their carbohydrate chains. The present study focused on the determination of antioxidant activity of the extracted polysaccharide fractions and elucidation of the structure of polysaccharides using nuclear magnetic resonance (NMR) spectroscopy. Homogalacturonan (HG), consisting of 1,4-linked residues of α-D-galactopyranosyluronic acid (GalpA), rhamnogalacturonan-I (RG-I), which contains a diglycosyl repeating unit with a strictly alternating sequence of 1,4-linked D-GalpA and 1,2-linked L-rhamnopyranose (Rhap) residues in the backbone, and arabinan, were identified as the structural units of the obtained polysaccharides. HMBC spectra showed that arabinan consisted of alternating regions formed by 3,5-substituted and 1,5-linked arabinofuranose residues, but there was no alternation of these residues in the arabinan structure. Polysaccharide fractions scavenged the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical at 0.2-1.8 mg/mL. The correlation analysis showed that the DPPH scavenging activity of polysaccharide fractions was associated with the content of phenolic compounds (PCs).
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Antioxidantes , Salsola , Antioxidantes/farmacologia , Pectinas/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Monossacarídeos/químicaRESUMO
Inherited retinal diseases (IRD) are a group of heterogeneous disorders, most of which lead to blindness with limited therapeutic options. Pathogenic variants in RBP4, coding for a major blood carrier of retinol, retinol-binding protein 4, are responsible for a peculiar form of IRD. The aim of this study was to investigate if retinal function of an RBP4-related IRD patient can be improved by retinol administration. Our patient presented a peculiar white-dot retinopathy, reminiscent of vitamin A deficient retinopathy. Using a customized next generation sequencing (NGS) IRD panel we discovered a novel loss-of-function homozygous pathogenic variant in RBP4: c.255G >A, p.(Trp85*). Western blotting revealed the absence of RBP4 protein in the patient's serum. Blood retinol levels were undetectable. The patient was put on a high-dose oral retinol regimen (50,000 UI twice a week). Subjective symptoms and retinal function markedly and sustainably improved at 5-months and 1-year follow-up. Here we show that this novel IRD case can be treated by oral retinol administration.
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Distrofias Retinianas , Vitamina A , Humanos , Retina/metabolismo , Distrofias Retinianas/tratamento farmacológico , Distrofias Retinianas/genética , Proteínas Plasmáticas de Ligação ao Retinol/genética , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Vitamina A/uso terapêuticoRESUMO
Variants in the X-linked retinitis pigmentosa GTPase regulator gene (RPGR) and, specifically, in its retinal opening reading frame-15 isoform (RPGRORF15) may cause rod-cone (RCD), cone, and cone-rod dystrophies (CDs and CRDs). While RPGR-related RCDs have been frequently evaluated, the characteristics and progression of RPGR-related CD/CRDs are largely unknown. Therefore, the goal of our work was to perform genotype-phenotype correlations specifically in RPGRORF15-related CD/CRDs. This retrospective longitudinal study included 34 index patients and two affected relatives with a molecular diagnosis of RPGR-related CD/CRDs. Patients were recruited at the "Quinze-Vingts" Hospital, Paris, France and screened for mutations in RPGRORF15 at the Institut de la Vision, Paris, France. We identified 29 distinct variants, of which 27 were truncating. All were located in the 3' half of the RPGRORF15 transcript. Twenty of them were novel. Fifteen subjects were affected by CD, the remaining had CRD. When analyzing the longitudinal data, a progressive decline in visual acuity (VA) was noted, with more than 60% of the patients reaching VA ≥ 1 LogMar in the best eye after the fifth decade of life. To our knowledge, this is the largest described study of a cohort of CD/CRD patients affected by RPGRORF15 variants. Longitudinal data showed a rapidly progressive disease, possibly locating an optimal window of intervention for future therapies in younger ages.
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Distrofias de Cones e Bastonetes , Proteínas do Olho , Retinose Pigmentar , Distrofias de Cones e Bastonetes/genética , Proteínas do Olho/genética , Genes Reguladores , Humanos , Estudos Longitudinais , Mutação , Linhagem , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética , Estudos RetrospectivosRESUMO
Biallelic gene defects in MFSD8 are not only a cause of the late-infantile form of neuronal ceroid lipofuscinosis, but also of rare isolated retinal degeneration. We report clinical and genetic data of seven patients compound heterozygous or homozygous for variants in MFSD8, issued from a French cohort with inherited retinal degeneration, and two additional patients retrieved from a Swiss cohort. Next-generation sequencing of large panels combined with whole-genome sequencing allowed for the identification of twelve variants from which seven were novel. Among them were one deep intronic variant c.998+1669A>G, one large deletion encompassing exon 9 and 10, and a silent change c.750A>G. Transcript analysis performed on patients' lymphoblastoid cell lines revealed the creation of a donor splice site by c.998+1669A>G, resulting in a 140 bp pseudoexon insertion in intron 10. Variant c.750A>G produced exon 8 skipping. In silico and in cellulo studies of these variants allowed us to assign the pathogenic effect, and showed that the combination of at least one severe variant with a moderate one leads to isolated retinal dystrophy, whereas the combination in trans of two severe variants is responsible for early onset severe retinal dystrophy in the context of late-infantile neuronal ceroid lipofuscinosis.
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Lipofuscinoses Ceroides Neuronais , Distrofias Retinianas , Éxons/genética , Homozigoto , Humanos , Proteínas de Membrana Transportadoras/genética , Mutação , Lipofuscinoses Ceroides Neuronais/genética , Distrofias Retinianas/genéticaRESUMO
PURPOSE: The concept of time perspective (TP) implies that a mental focus on past, present, or future affect a person makes decisions and take action. Inability to plan their life for a sufficiently long time perspective due to the COVID-19 pandemic appeared to have a pronounced impact on a human's lifestyle influencing their thoughts, feelings, and behaviors, including eating behavior. This study tested two hypotheses: (a) that during COVID-19 isolation, the incidence rate of food addiction is increased, and (b) people with present TP are more likely exhibited signs of food addiction (FA). METHODS: The final study sample included 949 people, mean age 21.8 ± 7.8 years (range: 17-71 years, women: 78.3%). Each participant indicated their personal data and completed Yale Food Addiction Scale and the Zimbardo Time Perspective Inventory. RESULTS: There was an increased incidence rate of FA (OR = 1.678, 95% CI = 1.324, 2.148, p = 0.000) during COVID-19 isolation. Individuals with balanced, future, and past positive TP were less likely to exhibit symptoms of FA. Persons with past negative, and present hedonistic TP were more likely to exhibit signs of FA. CONCLUSION: There was an increased incidence rate of FA during COVID-19 isolation. Persons with shortened time horizon are more likely to exhibit symptoms of FA. LEVEL OF EVIDENCE: Level V, cross-sectional descriptive study.
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COVID-19 , Dependência de Alimentos , Adolescente , Adulto , Estudos Transversais , Comportamento Alimentar , Feminino , Dependência de Alimentos/diagnóstico , Dependência de Alimentos/epidemiologia , Humanos , Pandemias , Inquéritos e Questionários , Adulto JovemRESUMO
Cyclic nucleotide-gated channel ß1 (CNGB1) encodes the 240-kDa ß subunit of the rod photoreceptor cyclic nucleotide-gated ion channel. Disease-causing sequence variants in CNGB1 lead to autosomal recessive rod-cone dystrophy/retinitis pigmentosa (RP). We herein present a comprehensive review and analysis of all previously reported CNGB1 sequence variants, and add 22 novel variants, thereby enlarging the spectrum to 84 variants in total, including 24 missense variants (two of which may also affect splicing), 21 nonsense, 19 splicing defects (7 at noncanonical positions), 10 small deletions, 1 small insertion, 1 small insertion-deletion, 7 small duplications, and 1 gross deletion. According to the American College of Medical Genetics and Genomics classification criteria, 59 variants were considered pathogenic or likely pathogenic and 25 were variants of uncertain significance. In addition, we provide further phenotypic data from 34 CNGB1-related RP cases, which, overall, are in line with previous findings suggesting that this form of RP has long-term retention of useful central vision despite the early onset of night blindness, which is valuable for patient counseling, but also has implications for it being considered a priority target for gene therapy trials.
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Distrofias de Cones e Bastonetes/genética , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Estudos de Coortes , Distrofias de Cones e Bastonetes/classificação , Distrofias de Cones e Bastonetes/epidemiologia , Distrofias de Cones e Bastonetes/patologia , Análise Mutacional de DNA , Estudos de Associação Genética , Humanos , MutaçãoRESUMO
Pathogenic variants in CRB1 lead to diverse recessive retinal disorders from severe Leber congenital amaurosis to isolated macular dystrophy. Until recently, no clear phenotype-genotype correlation and no appropriate mouse models existed. Herein, we reappraise the phenotype-genotype correlation of 50 patients with regards to the recently identified CRB1 isoforms: a canonical long isoform A localized in Müller cells (12 exons) and a short isoform B predominant in photoreceptors (7 exons). Twenty-eight patients with early onset retinal dystrophy (EORD) consistently had a severe Müller impairment, with variable impact on the photoreceptors, regardless of isoform B expression. Among them, two patients expressing wild type isoform B carried one variant in exon 12, which specifically damaged intracellular protein interactions in Müller cells. Thirteen retinitis pigmentosa patients had mainly missense variants in laminin G-like domains and expressed at least 50% of isoform A. Eight patients with the c.498_506del variant had macular dystrophy. In one family homozygous for the c.1562C>T variant, the brother had EORD and the sister macular dystrophy. In contrast with the mouse model, these data highlight the key role of Müller cells in the severity of CRB1-related dystrophies in humans, which should be taken into consideration for future clinical trials.
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Células Ependimogliais/patologia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Degeneração Macular/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Distrofias Retinianas/patologia , Retinose Pigmentar/patologia , Adolescente , Idade de Início , Processamento Alternativo , Criança , Pré-Escolar , Células Ependimogliais/metabolismo , Proteínas do Olho/química , Feminino , Estudos de Associação Genética , Humanos , Lactente , Degeneração Macular/genética , Degeneração Macular/metabolismo , Masculino , Proteínas de Membrana/química , Modelos Moleculares , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/química , Mutação Puntual , Distrofias Retinianas/genética , Distrofias Retinianas/metabolismo , Retinose Pigmentar/genética , Retinose Pigmentar/metabolismo , Estudos Retrospectivos , Deleção de Sequência , Adulto JovemRESUMO
Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects.
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Proteínas de Transporte/genética , Distrofias de Cones e Bastonetes/genética , Oftalmopatias Hereditárias/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação/genética , Distrofias Retinianas/genética , Adulto , Idoso , Criança , Pontos de Quebra do Cromossomo , Simulação por Computador , Distrofias de Cones e Bastonetes/fisiopatologia , Variações do Número de Cópias de DNA/genética , Eletrorretinografia , Oftalmopatias Hereditárias/fisiopatologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Distrofias Retinianas/fisiopatologiaRESUMO
The aim of this study was to isolate pectins with antioxidant activity from the leaves of Epilobium angustifolium L. Two pectins, EA-4.0 and EA-0.8, with galacturonic acid contents of 88 and 91% were isolated from the leaves of E. angustifolium L. by the treatment of plant raw materials with aqueous hydrochloric acid at pH 4.0 and 0.8, respectively. EA-4.0 and EA-0.8 were found to scavenge the DPPH radical in a concentration-dependent manner at 17-133 µg/mL, whereas commercial apple pectin scavenged at 0.5-2 mg/mL. The antioxidant activity of EA-4.0 was the highest and exceeded the activity of EA-0.8 and a commercial apple pectin by 2 and 39 times (IC50-0.050, 0.109 and 1.961 mg/mL), respectively. Pectins EA-4.0 and EA-0.8 were found to possess superoxide radical scavenging activity, with IC50s equal to 0.27 and 0.97 mg/mL, respectively. Correlation analysis of the composition and activity of 32 polysaccharide fractions obtained by enzyme hydrolysis and anionic exchange chromatography revealed that the antioxidant capacity of fireweed pectins is mainly due to phenolics and is partially associated with xylogalacturonan chains. The data obtained demonstrate that pectic polysaccharides appeared to be bioactive components of fireweed leaves with high antioxidant activity, which depend on pH at their extraction.
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Antioxidantes/farmacologia , Epilobium/química , Pectinas/química , Pectinas/isolamento & purificação , Compostos de Bifenilo/química , Fracionamento Químico , Citocromos c/metabolismo , Sequestradores de Radicais Livres/química , Pectinas/farmacologia , Picratos/química , Análise de Regressão , Superóxidos/química , Xantina Oxidase/metabolismoRESUMO
In this study, we report a novel duplication causing North Carolina macular dystrophy (NCMD) identified applying whole genome sequencing performed on eight affected members of two presumed unrelated families mapping to the MCDR1 locus. In our families, the NCMD phenotype was associated with a 98.4 kb tandem duplication encompassing the entire CCNC and PRDM13 genes and a common DNase 1 hypersensitivity site. To study the impact of PRDM13 or CCNC dysregulation, we used the Drosophila eye development as a model. Knock-down and overexpression of CycC and CG13296, Drosophila orthologues of CCNC and PRDM13, respectively, were induced separately during eye development. In flies, eye development was not affected, while knocking down either CycC or CG13296 mutant models. Overexpression of CycC also had no effect. Strikingly, overexpression of CG13296 in Drosophila leads to a severe loss of the imaginal eye-antennal disc. This study demonstrated for the first time in an animal model that overexpression of PRDM13 alone causes a severe abnormal retinal development. It is noteworthy that mutations associated with this autosomal dominant foveal developmental disorder are frequently duplications always including an entire copy of PRDM13, or variants in one DNase 1 hypersensitivity site at this locus.
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Distrofias Hereditárias da Córnea/genética , Ciclina C/genética , Histona-Lisina N-Metiltransferase/genética , Adulto , Animais , Mapeamento Cromossômico , Cromossomos Humanos Par 6 , Distrofias Hereditárias da Córnea/metabolismo , Ciclina C/metabolismo , Drosophila melanogaster , Proteínas do Olho/genética , Feminino , Ligação Genética , Haplótipos , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Masculino , Domínios PR-SET , Linhagem , Sequenciamento Completo do GenomaRESUMO
Child photophobia. Photophobia is abnormal intolerance of light. It is a commonest complaint and a reason for ophthalmological assessment in adults. Child photophobia is less frequent and must be explored. First of all, life-threatening pathology (meningitis) should be ruled off. Then, thorough ocular examination will establish a right diagnosis. Ocular surface alterations are prominent cause of photophobia. Retinal and optic pathway diseases could also lead to light aversion. This article is a systematic review of conditions linked with photophobia in children. It also offers a panorama of clinical imaging in typical cases.
Photophobie chez l'enfant. La photophobie est une intolérance anormale de la lumière. Elle est un motif fréquent de consultation en ophtalmologie adulte. Chez l'enfant, la photophobie est loin d'être banale et doit être explorée. Après avoir écarté une pathologie neurologique menaçant le pronostic visuel (méningite), l'examen oculaire permet d'en établir la cause. Bien que les maladies de surface oculaire dominent par leur fréquence, les pathologies de la rétine et du nerf optique peuvent aussi provoquer une photophobie. Une revue systématique des causes de photophobie chez l'enfant et un panorama iconographique sont présentés dans cet article.
Assuntos
Fotofobia , Adulto , Criança , HumanosRESUMO
INTRODUCTION: CABP4-related retinal dysfunction is a cone-rod synaptic transmission disorder with electronegative electroretinogram (ERG) waveform. It is a rare retinal dysfunction that can be classified into the incomplete form of congenital stationary night blindness. Absent foveal reflex and overall foveal thinning were previously reported, but in most cases the fundus appearance was described as nearly normal. We report here peculiar macular changes in a patient of French ancestry harbouring CABP4 mutations. METHODS: Complete ocular examination and full-field ERG were performed at the initial presentation and follow-up. Multimodal fundus imagining, including spectral-domain optical coherence tomography, colour, infrared reflectance and short-wavelength autofluorescence photographs, was performed during follow-up visits. RESULTS: A 7-month-old infant was addressed to our department for visual unresponsiveness and nystagmus. ERG had an electronegative waveform, even for light-adapted stimuli, thus supporting the diagnosis of photoreceptor-bipolar cell transmission disorder. Genetic investigations discovered a compound heterozygous mutation in CABP4: c.646C > T, p.Arg216*/c.673C > T, p.Arg225*. Multimodal fundus imaging, performed at follow-up visits, showed fine radial folds at the vitreomacular interface and dark foveal dots in both eyes. Optic coherence tomography revealed a focal foveal ellipsoid zone gap. DISCUSSION: Initial presentation was misleading with Leber congenital amaurosis. The electronegative ERG waveform reoriented the genetic investigations and thus establishing a correct diagnosis. To the best of our knowledge, the peculiar fundus changes observed in our patient were never reported before. We hypothesized that a foveal ellipsoid zone interruption discovered in our patient could reflect mostly a cone dysfunction. It was unclear whether the fine radial folds in both maculae were linked with high hyperopia or were an intrinsic feature of the retinal disease. CONCLUSION: CABP4-related retinal disease is a cone-rod system disorder with possible foveal abnormalities.
Assuntos
Proteínas de Ligação ao Cálcio/genética , Oftalmopatias Hereditárias/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Mutação , Miopia/diagnóstico , Cegueira Noturna/diagnóstico , Células Fotorreceptoras de Vertebrados/patologia , Doenças Retinianas/diagnóstico , Doenças Retinianas/genética , Eletrorretinografia , Oftalmopatias Hereditárias/genética , Oftalmopatias Hereditárias/fisiopatologia , Angiofluoresceinografia , França/epidemiologia , Fundo de Olho , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Humanos , Lactente , Masculino , Miopia/genética , Miopia/fisiopatologia , Cegueira Noturna/genética , Cegueira Noturna/fisiopatologia , Linhagem , Doenças Retinianas/fisiopatologia , Estudos Retrospectivos , Tomografia de Coerência Óptica/métodos , Acuidade Visual , População Branca/genéticaRESUMO
INTRODUCTION: Oligocone trichromacy (OT) is an uncommon cone dysfunction disorder, the mechanism of which remains poorly understood. OT has been thought to be non-progressive, but its long-term visual outcome has been seldom reported in the literature. Our aim was to present two OT patients followed at our institution over 18 years. MATERIALS AND METHODS: Complete ocular examination, color vision, visual fields, and full-field electroretinography (ERG) were performed at initial presentation and follow-up. Spectral-domain optical coherence tomography (OCT) was performed during follow-up when available at our institution. RESULTS: Initial ocular examination showed satisfactory visual acuities with normal fundus examination and near-to-normal color vision. However, computerized perimetry demonstrated a ring-shaped scotoma around fixation, and ERG showed a profound cone dysfunction. The discrepancy between preserved color vision and profound cone dysfunction leads to the diagnosis of OT. Subsequent follow-ups over 18 years showed subtle degradation of visual acuities along with progression of the myopia in both patients and slight worsening of color vision in one patient. Initial OCT revealed a focal interruption of the ellipsoid line along with decreased thickness of the perifoveal macula. Subsequent OCT imaging performed 2 years later did not show any macular changes. CONCLUSION: Although OT is known to be a non-progressive cone dysfunction, our results suggest that subtle degradation of the visual function might happen over time.