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Age-related cataracts is a highly prevalent eye disorder that results in the clouding of the crystalline lens and is one of the leading causes of visual impairment and blindness. The disease is influenced by multiple factors including genetics, prolonged exposure to ultraviolet radiation, and a history of diabetes. However, the extent to which each of these factors contributes to the development of cataracts remains unclear. Our study identified 101 independent genome-wide significant loci, 57 of which are novel. We identified multiple genes and biological pathways associated with the cataracts, including four drug-gene interactions. Our results suggest a causal association between type 1 diabetes and cataracts. Also, we highlighted a surrogate measure of UV light exposure as a marker of cataract risk in adults.
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Catarata , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Catarata/genética , Humanos , Raios Ultravioleta/efeitos adversos , Polimorfismo de Nucleotídeo Único , Diabetes Mellitus Tipo 1/genética , Envelhecimento/genéticaRESUMO
BACKGROUND: An ongoing challenge with rare diseases is limited data and, consequently, limited knowledge about the collective prevalence and impact of these conditions on individuals, families, and the health system, particularly in rural and regional areas. Using existing datasets, this project aimed to examine the epidemiology of and hospital activity for Tasmanians with rare diseases. METHODS: Rare diseases were defined as non-infectious diseases with a prevalence of less than 1 in 2000. An initial resource set of 1028 ICD-10-AM diagnostic codes was used to identify a cohort of Tasmanians with rare diseases in Tasmanian Health datasets (1 January 2007 until 31 December 2020). Validating the resource set using a small group with known rare diseases revealed limitations in ascertainment, and so an expanded set of 1940 ICD-10-AM diagnostic codes was developed by cross-referencing ICD-10-AM codes with Orphanet data. Cohort hospital activity and admission costs were compared to statewide data for the final year of the study, 01 January 2020 to 31 December 2020. RESULTS: Using the resource set of 1028 ICD-10-AM diagnostic codes, the period prevalence of rare diseases in Tasmania across all age groups was estimated at 3.5%, with a point prevalence of 1.5% in December 2020. In 2020, 3384 individuals within the Tasmanian rare disease cohort, representing 0.6% of the Tasmanian population, accessed the public hospital system and accounted for 5.6% of all admissions. The mean length of stay for rare disease-related hospital admissions was 5.0 days, compared to 3.3 days for non-rare disease-related admissions. The mean cost per admission for the rare disease cohort was AUD$11,310, compared to AUD$6475 for all admissions statewide. In 2020, using the expanded resource set, the total cost of public hospital admissions in Tasmania was estimated to be AUD$979 million, with rare disease-related hospital admissions accounting for 9.1% of this cost, increasing to 19.0% when the costs for all admissions for the rare disease patients were included. CONCLUSIONS: Patients with rare diseases had more admissions, longer length of stay, and a higher average cost per admission. Patients with rare diseases have a disproportionate impact on statewide hospital activity and costs in Tasmania.
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Doenças Raras , Humanos , Tasmânia/epidemiologia , Doenças Raras/epidemiologia , Masculino , Feminino , Prevalência , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Criança , Classificação Internacional de Doenças , Pessoa de Meia-Idade , Pré-Escolar , Adulto Jovem , LactenteRESUMO
Zebrafish are an outstanding model for assessing the involvement of genes in paediatric cataracts. Gene discovery for cataracts is enhanced by manipulation of the genome of zebrafish embryos and comparing the phenotypes of mutant progeny with the wildtype embryos. However, wildtype laboratory fish can also develop cataracts, potentially confounding the results. In this study, we compared the baseline cataract rate between two commonly used wildtype laboratory strains, AB and TL, and also an outbred transgenic line with mCherry reporter. We assessed a total of 805 lens images of fish at 4 days post-fertilisation for cataracts and scored each cataract observed as mild, moderate or severe. We found that the AB strain had a cataract rate of 16.2%, TL had 8.9%, and mCherry had 0.7% and these rates were significantly different. We found that TL strain had a lower rate of mild cataracts than AB fish, however, the rate of moderate and severe phenotypes in the AB and the TL strain was similar. Overall, we showed that the baseline cataract rate varies significantly between the strains housed in a single facility and conclude that baseline rates of cataracts should be assessed when planning experiments to assess the genetic causes of cataracts.
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Animais Geneticamente Modificados , Catarata , Modelos Animais de Doenças , Cristalino , Fenótipo , Peixe-Zebra , Animais , Peixe-Zebra/genética , Catarata/genética , Cristalino/patologiaRESUMO
Prostate cancer is one of the most commonly diagnosed cancers in men and unfortunately, disease will progress in up to a third of patients despite primary treatment. Currently, there is a significant lack of prognostic tests that accurately predict disease course; however, the acquisition of somatic chromosomal variation in the form of DNA copy number variants may help understand disease progression. Notably, studies have found that a higher burden of somatic copy number alterations (SCNA) correlates with more aggressive disease, recurrence after surgery and metastasis. Here we will review the literature surrounding SCNA formation, including the roles of key tumour suppressors and oncogenes (PTEN, BRCA2, NKX3.1, ERG and AR), and their potential to inform diagnostic and prognostic clinical testing to improve predictive value. Ultimately, SCNAs, or inherited germline alterations that predispose to SCNAs, could have significant clinical utility in diagnostic and prognostic tests, in addition to guiding therapeutic selection.
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Variações do Número de Cópias de DNA , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Oncogenes , Prognóstico , Progressão da DoençaRESUMO
Diabetic retinopathy (DR) is the most common microvascular complication related to diabetes. There is evidence that genetics play an important role in DR pathogenesis, but the complexity of the disease makes genetic studies a challenge. This chapter is a practical overview of the basic steps for genome-wide association studies with respect to DR and its associated traits. Also described are approaches that can be adopted in future DR studies. This is intended to serve as a guide for beginners and to provide a framework for further in-depth analysis.
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Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Diabetes Mellitus Tipo 2/genética , Retinopatia Diabética/genética , Estudo de Associação Genômica Ampla/métodos , FenótipoRESUMO
BACKGROUND: Intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections are the standard of care for diabetic macular edema (DME), a common complication of diabetes. This study aimed to identify factors influencing DME intravitreal anti-VEGF treatment outcomes in real-world practice. METHODS: This was a multi-center retrospective observational study using medical chart review of participants receiving anti-VEGF injections for DME (N = 248). Demographic and clinical variables were assessed for association with best corrected visual acuity (BCVA) and central macular thickness (CMT) outcomes using regression models. RESULTS: There was a significant improvement in BCVA (p < 0.001) and CMT (p < 0.001) after 12 months of treatment, although 21% of participants had decreased BCVA, and 41% had a < 10% CMT reduction at 12 months. Higher baseline BCVA (p = 0.022, OR=-0.024, 95% CI=-0.046,-0.004) and longer duration of diabetic retinopathy (p = 0.048, OR=-0.064, 95% CI=-0.129,-0.001) were negative predictors for BCVA response, whereas Aflibercept treatment (p = 0.017, OR = 1.107, 95% CI = 0.220,2.051) compared with other drugs and a positive "early functional response" (p < 0.001, OR=-1.393, 95% CI=-1.946,-0.857) were positive predictors. A higher baseline CMT (p < 0.001, OR = 0.019, 95% CI = 0.012,0.0261) and an "early anatomical response", (p < 0.001, OR=-1.677, 95% CI=-2.456, -0.943) were predictors for greater reduction in CMT. Overall, the variables could predict only 23% of BCVA and 52% of CMT response. CONCLUSIONS: The study shows a significant proportion of DME patients do not respond to anti-VEGF therapy and identifies several clinical predictors for treatment outcomes. TRIAL REGISTRATION: The study was approved through the Human Research Ethics Committee, University of Tasmania (approval number H0012902), and the Southern Adelaide Clinical Human Research Ethics Committee (approval number 86 - 067).
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BACKGROUND: There are currently no specific biomarkers for multiple sclerosis (MS). Identifying robust biomarkers for MS is crucial to improve disease diagnosis and management. METHODS: This study first used six Mendelian randomisation methods to assess causal relationship of 174 metabolites with MS, incorporating data from European-ancestry metabolomics (n=8569-86 507) and MS (n=14 802 MS cases, 26 703 controls) genomewide association studies. Genetic scores for identified causal metabolite(s) were then computed to predict MS disability progression in an independent longitudinal cohort (AusLong study) of 203 MS cases with up to 15-year follow-up. RESULTS: We found a novel genetic causal effect of serine on MS onset (OR=1.67, 95% CI 1.51 to 1.84, p=1.73×10-20), such that individuals whose serine level is 1 SD above the population mean will have 1.67 times the risk of developing MS. This is robust across all sensitivity methods (OR ranges from 1.49 to 1.67). In an independent longitudinal MS cohort, we then constructed time-dynamic and time-fixed genetic scores based on serine genetic instrument single-nucleotide polymorphisms, where higher scores for raised serum serine level were associated with increased risk of disability worsening, especially in the time-dynamic model (RR=1.25, 95% CI 1.10 to 1.42, p=7.52×10-4). CONCLUSIONS: These findings support investigating serine as an important candidate biomarker for MS onset and disability progression.
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Pessoas com Deficiência , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/genética , Causalidade , Metabolômica , Biomarcadores , Progressão da DoençaRESUMO
Understanding how variations in the plasma and brain proteome contribute to multiple sclerosis susceptibility can provide important insights to guide drug repurposing and therapeutic development for the disease. However, the role of genetically predicted protein abundance in multiple sclerosis remains largely unknown. Integrating plasma proteomics (n = 3301) and brain proteomics (n = 376 discovery; n = 152 replication) into multiple sclerosis genome-wide association studies (n = 14 802 cases and 26 703 controls), we employed summary-based methods to identify candidate proteins involved in multiple sclerosis susceptibility. Next, we evaluated associations of the corresponding genes with multiple sclerosis at tissue-level using large gene expression quantitative trait data from whole-blood (n = 31 684) and brain (n = 1194) tissue. Further, to assess transcriptional profiles for candidate proteins at cell-level, we examined gene expression patterns in immune cell types (Dataset 1: n = 73 cases and 97 controls; Dataset 2: n = 31 cases and 31 controls) for identified plasma proteins, and in brain cell types (Dataset 1: n = 4 cases and 5 controls; Dataset 2: n = 5 cases and 3 controls) for identified brain proteins. In a longitudinal multiple sclerosis cohort (n = 203 cases followed up to 15 years), we also assessed the corresponding gene-level associations with the outcome of disability worsening. We identified 39 novel proteins associated with multiple sclerosis risk. Based on five identified plasma proteins, four available corresponding gene candidates showed consistent associations with multiple sclerosis risk in whole-blood, and we found TAPBPL upregulation in multiple sclerosis B cells, CD8+ T cells and natural killer cells compared with controls. Among the 34 candidate brain proteins, 18 were replicated in a smaller cohort and 14 of 21 available corresponding gene candidates also showed consistent associations with multiple sclerosis risk in brain tissue. In cell-specific analysis, six identified brain candidates showed consistent differential gene expression in neuron and oligodendrocyte cell clusters. Based on the 39 protein-coding genes, we found 23 genes that were associated with disability worsening in multiple sclerosis cases. The findings present a set of candidate protein biomarkers for multiple sclerosis, reinforced by high concordance in downstream transcriptomics findings at tissue-level. This study also highlights the heterogeneity of cell-specific transcriptional profiles for the identified proteins and that numerous candidates were also implicated in disease progression. Together, these findings can serve as an important anchor for future studies of disease mechanisms and therapeutic development.
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Esclerose Múltipla , Humanos , Esclerose Múltipla/genética , Estudo de Associação Genômica Ampla , Biomarcadores , Proteínas Sanguíneas/genética , Encéfalo , Imunoglobulinas/genética , Proteínas de Membrana/genéticaRESUMO
The standardization of variant curation criteria is essential for accurate interpretation of genetic results and clinical care of patients. The variant curation guidelines developed by the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) in 2015 are widely used but are not gene specific. To address this issue, the Clinical Genome Resource (ClinGen) Variant Curation Expert Panels (VCEP) have been tasked with developing gene-specific variant curation guidelines. The Glaucoma VCEP was created to develop rule specifications for genes associated with primary glaucoma, including myocilin (MYOC), the most common cause of Mendelian glaucoma. Of the 28 ACMG/AMP criteria, the Glaucoma VCEP adapted 15 rules to MYOC and determined 13 rules not applicable. Key specifications included determining minor allele frequency thresholds, developing an approach to counting probands and segregations, and reviewing functional assays. The rules were piloted on 81 variants and led to a change in classification in 40% of those that were classified in ClinVar, with functional evidence influencing the classification of 18 variants. The standardized variant curation guidelines for MYOC provide a framework for the consistent application of the rules between laboratories, to improve MYOC genetic testing in the management of glaucoma.
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Genoma Humano , Glaucoma , Humanos , Testes Genéticos/métodos , Variação Genética , Glaucoma/diagnóstico , Glaucoma/genética , Patologia Molecular , Estados UnidosRESUMO
OBJECTIVE: Paediatric (childhood or congenital) cataract is an opacification of the normally clear lens of the eye and has a genetic basis in at least 18% of cases in Australia. This study aimed to replicate clinical gene screening to identify variants likely to be causative of disease in an Australian patient cohort. METHODS AND ANALYSIS: Sixty-three reported isolated cataract genes were screened for rare coding variants in 37 Australian families using genome sequencing. RESULTS: Disease-causing variants were confirmed in eight families with variant classification as 'likely pathogenic'. This included novel variants PITX3 p.(Ter303LeuextTer100), BFSP1 p.(Glu375GlyfsTer2), and GJA8 p.(Pro189Ser), as well as, previously described variants identified in genes GJA3, GJA8, CRYAA, BFSP1, PITX3, COL4A1 and HSF4. Additionally, eight variants of uncertain significance with evidence towards pathogenicity were identified in genes: GJA3, GJA8, LEMD2, PRX, CRYBB1, BFSP2, and MIP. CONCLUSION: These findings expand the genotype-phenotype correlations of both pathogenic and benign variation in cataract-associated genes. They further emphasise the need to develop additional evidence such as functional assays and variant classification criteria specific to paediatric cataract genes to improve interpretation of variants and molecular diagnosis in patients.
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Catarata , Cristalino , Austrália , Catarata/diagnóstico , Humanos , Cristalino/patologia , Proteínas de Membrana/genética , Mutação , Proteínas Nucleares/genética , LinhagemRESUMO
Corneal dystrophies describe a clinically and genetically heterogeneous group of inherited disorders. The International Classification of Corneal Dystrophies (IC3D) lists 22 types of corneal dystrophy, 17 of which have been demonstrated to result from pathogenic variants in 19 identified genes. In this study, we investigated the diagnostic yield of genetic testing in a well-characterised cohort of 58 individuals from 44 families with different types of corneal dystrophy. Individuals diagnosed solely with Fuchs endothelial corneal dystrophy were excluded. Clinical details were obtained from the treating ophthalmologist. Participants and their family members were tested using a gene candidate and exome sequencing approach. We identified a likely molecular diagnosis in 70.5% families (31/44). The detection rate was significantly higher among probands with a family history of corneal dystrophy (15/16, 93.8%) than those without (16/28, 57.1%, p = .015), and among those who had undergone corneal graft surgery (9/9, 100.0%) compared to those who had not (22/35, 62.9%, p = .041). We identified eight novel variants in five genes and identified five families with syndromes associated with corneal dystrophies. Our findings highlight the genetic heterogeneity of corneal dystrophies and the clinical utility of genetic testing in reaching an accurate clinical diagnosis.
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Distrofias Hereditárias da Córnea , Austrália , Estudos de Coortes , Distrofias Hereditárias da Córnea/diagnóstico , Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/patologia , Testes Genéticos , HumanosRESUMO
Multiple sclerosis (MS) is a complex neuroinflammatory/degenerative disease of the central nervous system (CNS) that results in the formation of demyelinated lesions and axon degeneration. MS aetiology is complex, with genetics estimated to account for â¼48% of MS risk (International Multiple Sclerosis Genetics Consortium, 2019). Despite this, families with a high incidence of MS are rare. We have generated four induced pluripotent stem cell (iPSC) lines from individuals with relapsing-remitting and secondary progressive MS within a single family. The generation of disease-specific iPSC lines from multiple members of a single family will facilitate MS genetic and functional studies.
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Células-Tronco Pluripotentes Induzidas , Esclerose Múltipla , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Esclerose Múltipla/metabolismo , RecidivaRESUMO
Intraocular anti-vascular endothelial growth factor (VEGF) therapies are the front-line treatment for diabetic macular edema (DME); however, treatment response varies widely. This study aimed to identify genetic determinants associated with anti-VEGF treatment response in DME. We performed a genome-wide association study on 220 Australian patients with DME treated with anti-VEGF therapy, genotyped on the Illumina Global Screening Array, and imputed to the Haplotype Reference Consortium panel. The primary outcome measures were changes in central macular thickness (CMT in microns) and best-corrected visual acuity (BCVA in ETDRS letters) after 12 months. Association between single nucleotide polymorphism (SNP) genotypes and DME outcomes were evaluated by linear regression, adjusting for the first three principal components, age, baseline CMT/BCVA, duration of diabetic retinopathy, and HbA1c. Two loci reached genome-wide significance (p < 5 × 10−8) for association with increased CMT: a single SNP on chromosome 6 near CASC15 (rs78466540, p = 1.16 × 10−9) and a locus on chromosome 12 near RP11-116D17.1 (top SNP rs11614480, p = 2.69 × 10−8). Four loci were significantly associated with reduction in BCVA: two loci on chromosome 11, downstream of NTM (top SNP rs148980760, p = 5.30 × 10−9) and intronic in RP11-744N12.3 (top SNP rs57801753, p = 1.71 × 10−8); one near PGAM1P1 on chromosome 5 (rs187876551, p = 1.52 × 10−8); and one near TBC1D32 on chromosome 6 (rs118074968, p = 4.94 × 10−8). In silico investigations of each locus identified multiple expression quantitative trait loci and potentially relevant candidate genes warranting further analysis. Thus, we identified multiple genetic loci predicting treatment outcomes for anti-VEGF therapies in DME. This work may potentially lead to managing DME using personalized treatment approaches.
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Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Proteínas Adaptadoras de Transdução de Sinal , Inibidores da Angiogênese/uso terapêutico , Austrália , Diabetes Mellitus/tratamento farmacológico , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/genética , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Humanos , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Edema Macular/genética , Ranibizumab/uso terapêutico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Fatores de Crescimento do Endotélio Vascular , Acuidade VisualRESUMO
OBJECTIVES: To assess whether insulin therapy impacts the effectiveness of anti-vascular endothelial growth factor (anti-VEGF) injection for the treatment of diabetic macular edema (DME) in type 2 diabetes mellitus. METHODS: This was a retrospective multi-center analysis. The best-corrected visual acuity (BCVA) at 12 months, BCVA change, central macular thickness (CMT), CMT change, and cumulative injection number were compared between the insulin and the oral hypoglycemic agent (OHA) groups. RESULTS: The mean final BCVA and CMT improved in both the insulin (N = 137; p < 0.001; p < 0.001, respectively) and the OHA group (N = 61; p = 0.199; p < 0.001, respectively). The two treatment groups were comparable for final BCVA (p = 0.263), BCVA change (p = 0.184), final CMT (p = 0.741), CMT change (p = 0.458), and the cumulative injections received (p = 0.594). The results were comparable between the two groups when stratified by baseline vision (p > 0.05) and baseline HbA1c (p > 0.05). CONCLUSION: Insulin therapy does not alter treatment outcomes for anti-VEGF therapy in DME.
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Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Edema Macular , Inibidores da Angiogênese/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Retinopatia Diabética/complicações , Retinopatia Diabética/tratamento farmacológico , Humanos , Insulina/uso terapêutico , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Estudos Retrospectivos , Resultado do Tratamento , Acuidade VisualRESUMO
Advances in genome sequencing technologies have unlocked new possibilities in identifying disease-associated and causative genetic markers, which may in turn enhance disease diagnosis and improve prognostication and management strategies. With the capability of examining genetic variations ranging from single-nucleotide mutations to large structural variants, whole-genome sequencing (WGS) is an increasingly adopted approach to dissect the complex genetic architecture of neurologic diseases. There is emerging evidence for different structural variants and their roles in major neurologic and neurodevelopmental diseases. This review first describes different structural variants and their implicated roles in major neurologic and neurodevelopmental diseases, and then discusses the clinical relevance of WGS applications in neurology. Notably, WGS-based detection of structural variants has shown promising potential in enhancing diagnostic power of genetic tests in clinical settings. Ongoing WGS-based research in structural variations and quantifying mutational constraints can also yield clinical benefits by improving variant interpretation and disease diagnosis, while supporting biomarker discovery and therapeutic development. As a result, wider integration of WGS technologies into health care will likely increase diagnostic yields in difficult-to-diagnose conditions and define potential therapeutic targets or intervention points for genome-editing strategies.
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Multiple sclerosis (MS) is a chronic autoimmune and neurodegenerative disease that results in immune cell infiltration of the central nervous system (CNS) and demyelination in young adults. Substantial progress has been made in developing disease modifying therapies for people with relapsing-remitting MS, but options remain limited for people with primary progressive MS (PPMS). PPMS accounts for â¼15% of MS diagnoses. Herein, we generated a human induced pluripotent stem cell line (hiPSC) from a person with clinically definite PPMS. This disease-specific hiPSC line will be useful for studying PPMS in vitro, allowing the generation of immune and CNS cell types.
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Purpose: Age-related cataract is the leading cause of blindness worldwide. Variants in the EPHA2 gene increase the disease risk, and its knockout in mice causes cataract. We investigated whether age, sex, and genetic background, risk factors for age-related cataract, and Epha2 genotype influence Epha2-related cataract development in mice. Methods: Cataract development was monitored in Epha2+/+, Epha2+/-, and Epha2-/- mice (Epha2Gt(KST085)Byg) on C57BL/6J and FVB:C57BL/6J (50:50) backgrounds. Cellular architecture of lenses, endoplasmic reticulum (ER) stress, and redox state were determined using histological, molecular, and analytical techniques. Results: Epha2-/- and Epha2+/- mice on C57BL/6J background developed severe cortical cataracts by 18 and 38 weeks of age, respectively, compared to development of similar cataract significantly later in Epha2-/- mice and no cataract in Epha2+/- mice in this strain on FVB background, which was previously reported. On FVB:C57BL/6J background, Epha2-/- mice developed severe cortical cataract by 38 weeks and Epha2+/- mice exhibited mild cortical cataract up to 64 weeks of age. Progression of cataract in Epha2-/- and Epha2+/- female mice on C57BL/6J and mixed background, respectively, was slower than in matched male mice. N-cadherin and ß-catenin immunolabeling showed disorganized lens fiber cells and disruption of lens architecture in Epha2-/- and Epha2+/- lenses, coinciding with development of severe cataracts. EPHA2 immunolabeling showed intracellular accumulation of the mutant EPHA2-ß-galactosidase fusion protein that induced a cytoprotective ER stress response and in Epha2+/- lenses was also accompanied by glutathione redox imbalance. Conclusions: Both, Epha2-/- and Epha2+/- mice develop age-related cortical cataract; age as a function of Epha2 genotype, sex, and genetic background influence Epha2-related cataractogenesis in mice.
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Catarata/genética , Regulação da Expressão Gênica , Cristalino/metabolismo , RNA/genética , Receptor EphA2/genética , Animais , Catarata/diagnóstico , Catarata/metabolismo , Modelos Animais de Doenças , Genótipo , Cristalino/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor EphA2/biossínteseRESUMO
Genomic testing assesses many genes in one test. It is often used in the diagnosis of heterogeneous single gene disorders where pathogenic variation in one of many genes are known to cause similar phenotypes, or where a clinical diagnosis is difficult to reach. In the ophthalmic setting, genomic testing can be used to diagnose several groups of diseases, including inherited retinal dystrophies, paediatric cataract, glaucoma and anterior segment dysgenesis and other syndromic developmental disorders with eye involvement. The testing can encompass several modalities ranging from whole genome sequencing to exome sequencing or targeted gene panels. The advantages to the patient of receiving a molecular diagnosis include an end to the diagnostic odyssey, determination of prognosis and clarification of treatment, access to accurate genetic counselling, and confirming eligibility for clinical trials or genetic specific therapies. Genomic testing is a powerful addition to the diagnosis and management of inherited eye disease.
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Anormalidades do Olho , Oftalmopatias Hereditárias , Oftalmologia , Distrofias Retinianas , Criança , Anormalidades do Olho/genética , Oftalmopatias Hereditárias/diagnóstico , Oftalmopatias Hereditárias/genética , Testes Genéticos , Humanos , Distrofias Retinianas/genéticaRESUMO
Fuchs' endothelial corneal dystrophy (FECD) is a progressive vision impairing disease caused by thickening of Descemet's membrane and gradual degeneration and loss of corneal endothelial cells. The aim of this study was to identify differentially expressed genes between FECD-affected and unaffected corneal endothelium to gain insight into the pathophysiological mechanisms underlying this disease. Microarray gene expression analysis was performed on total RNA from FECD-affected and unaffected corneal endothelium-Descemet's membrane (CE-DM) specimens using the Illumina HumanHT-12 v4.0 expression array. RNA from pools of FECD-affected (n = 3 per pool) and individual unaffected (n = 3) specimens was used for comparison. Altered expression of a sub-set of differentially expressed genes was validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in independent specimens. Bioinformatics analysis was performed using InnateDB to reveal functional relationships among the differentially expressed genes and molecular pathways involved in the disease. A total of 16,513 genes were found expressed in the corneal endothelium of which 142 genes were differentially expressed between FECD-affected and unaffected endothelium (log2 fold-change ≥1.5, corrected p-value ≤0.05). Most of the genes were up-regulated (126) and a small proportion down-regulated (16) in affected corneal endothelium. Of the twelve genes prioritised for validation, differential expression of 10 genes, including those ranked 57th and 81st by significance validated by qRT-PCR (8 up-regulated and 2 downregulated, corrected p ≤ 0.05), one gene showed a trend for up-regulation in affected endothelium, consistent with the microarray analysis and another was up-regulated in an independent study indicating robustness of the differential expression dataset. Bioinformatic analysis revealed significant over-representation of differentially expressed genes in extracellular matrix reorganisation, cellular remodelling, immune response, and inflammation. Network analysis showed functional inter-relatedness of the majority of the dysregulated genes and revealed known direct functional relationships between 20 of the genes; many of these genes have roles in macrophage differentiation, phagocytosis and inflammation. This is the second report of microarray gene expression analysis in FECD. This study revealed a set of highly dysregulated genes in the corneal endothelium in FECD. More than a third of the dysregulated genes in the disease have been discovered for the first time and thus are novel. The dysregulated genes strongly suggest the presence of phagocytic cells, most likely immune cells, and inflammation in corneal endothelium in the disease. This study provides a molecular framework for delineating the mechanisms underlying these cellular processes in FECD.
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Endotélio Corneano/metabolismo , Proteínas do Olho/genética , Distrofia Endotelial de Fuchs/genética , Regulação da Expressão Gênica/fisiologia , Fagócitos/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Feminino , Distrofia Endotelial de Fuchs/fisiopatologia , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise Serial de Proteínas , RNA/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
OBJECTIVE: To compare the visual outcomes of intravitreal antivascular endothelial growth factor (anti-VEGF) injections in neovascular age-related macular degeneration (nAMD), diabetic macular oedema (DMO) and retinal vein occlusion (RVO) in a real-world setting. METHODS AND ANALYSIS: Retrospective analysis of data from the Tasmanian Ophthalmic Biobank database. The median change in best-corrected visual acuity (BCVA) between baseline and 12 months post initiating intravitreal anti-VEGF treatment were compared between the three diseases. Final BCVA, central macular thickness (CMT), cumulative number of injections and overall predictors of change in BCVA and CMT were also determined. RESULTS: At 12 months, change in BCVA was significantly different between nAMD, DMO and RVO cohorts (p=0.032), with lower median change for DMO (2 letters, range -5 to 20) than for RVO (11 letters, range -20 to 35). Likewise, CMT change was significantly different between the three cohorts (p=0.022), with a smaller reduction in CMT in DMO (-54 µm, range -482 to 50) than RVO patients (-137 µm, range -478 to 43; p=0.033). Total number of injections received (p=0.028) and final BCVA score (p=0.024) were also significantly different between the groups. Baseline BCVA was a negative predictor (p=0.042) and baseline CMT a positive predictor (p<0.001) of outcome. After adjusting for baseline BCVA and CMT, diagnosis of nAMD or RVO was a predictor of visual improvement compared with the DMO. CONCLUSIONS: At the end of 12 months, nAMD and RVO cohorts had the greatest improvement in BCVA, however the final BCVA for DMO was significantly better than for nAMD.