Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Hum Mol Genet ; 31(6): 875-887, 2022 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-34605899

RESUMEN

MicroRNAs (miRNAs) are small post-transcriptional regulators that offer promising targets for treating complex diseases. To this end, hsa-miR-4513 is an excellent candidate as this gene harbors within its conserved heptametrical seed sequence a frequent polymorphism (rs2168518), which has previously been associated with several complex phenotypes. So far, little is known about the biological mechanism(s) underlying these associations. In an initial step, we now aimed to identify allele-specific target genes of hsa-miR-4513. We performed RNA sequencing in a miRNA overexpression model in human umbilical vein endothelial cells transfected with separated hsa-miR-4513 alleles at rs2168518, namely hsa-miR-4513-G and hsa-miR-4513-A. Genes specifically regulated by the rs2168518 alleles were independently verified by quantitative reverse transcription PCR (qRT-PCR), western blot analysis and allele-specific miRNA binding via a luciferase reporter assay. By a text-based search publicly available databases such as Online Mendelian Inheritance in Man and Mouse Genome Informatics were utilized to link target genes of hsa-miR-4513 to previously described phenotypes. Overall, we identified 23 allele-specific hsa-miR-4513 target genes and replicated 19 of those independently via qRT-PCR. Western blot analysis and luciferase reporter assays conducted for an exemplary subsample further confirmed the allele-specific regulation of these genes by hsa-miR-4513. Remarkably, multiple allele-specific target genes identified are linked via text retrieval to several phenotypes previously reported to be associated with hsa-miR-4513. These genes offer promising candidates for ongoing research on the functional pathobiological impact of hsa-miR-4513 and its seed polymorphism rs2168518. This could give rise to therapeutic applications targeting this miRNA.


Asunto(s)
Células Endoteliales , MicroARNs , Alelos , Animales , Células Endoteliales/metabolismo , Regulación de la Expresión Génica/genética , Humanos , Ratones , MicroARNs/metabolismo
2.
PLoS Genet ; 16(9): e1008934, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32870927

RESUMEN

Significant association signals from genome-wide association studies (GWAS) point to genomic regions of interest. However, for most loci the causative genetic variant remains undefined. Determining expression quantitative trait loci (eQTL) in a disease relevant tissue is an excellent approach to zoom in on disease- or trait-associated association signals and hitherto on relevant disease mechanisms. To this end, we explored regulation of gene expression in healthy retina (n = 311) and generated the largest cis-eQTL data set available to date. Genotype- and RNA-Seq data underwent rigorous quality control protocols before FastQTL was applied to assess the influence of genetic markers on local (cis) gene expression. Our analysis identified 403,151 significant eQTL variants (eVariants) that regulate 3,007 genes (eGenes) (Q-Value < 0.05). A conditional analysis revealed 744 independent secondary eQTL signals for 598 of the 3,007 eGenes. Interestingly, 99,165 (24.71%) of all unique eVariants regulate the expression of more than one eGene. Filtering the dataset for eVariants regulating three or more eGenes revealed 96 potential regulatory clusters. Of these, 31 harbour 130 genes which are partially regulated by the same genetic signal. To correlate eQTL and association signals, GWAS data from twelve complex eye diseases or traits were included and resulted in identification of 80 eGenes with potential association. Remarkably, expression of 10 genes is regulated by eVariants associated with multiple eye diseases or traits. In conclusion, we generated a unique catalogue of gene expression regulation in healthy retinal tissue and applied this resource to identify potentially pleiotropic effects in highly prevalent human eye diseases. Our study provides an excellent basis to further explore mechanisms of various retinal disease etiologies.


Asunto(s)
Retina/metabolismo , Retina/fisiología , Enfermedades de la Retina/genética , Autopsia , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Estudio de Asociación del Genoma Completo/métodos , Genómica/métodos , Genotipo , Voluntarios Sanos , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética
3.
Exp Eye Res ; 225: 109248, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36108770

RESUMEN

Genomic studies in age-related macular degeneration (AMD) have identified genetic variants that account for the majority of AMD risk. An important next step is to understand the functional consequences and downstream effects of the identified AMD-associated genetic variants. Instrumental for this next step are 'omics' technologies, which enable high-throughput characterization and quantification of biological molecules, and subsequent integration of genomics with these omics datasets, a field referred to as systems genomics. Single cell sequencing studies of the retina and choroid demonstrated that the majority of candidate AMD genes identified through genomic studies are expressed in non-neuronal cells, such as the retinal pigment epithelium (RPE), glia, myeloid and choroidal cells, highlighting that many different retinal and choroidal cell types contribute to the pathogenesis of AMD. Expression quantitative trait locus (eQTL) studies in retinal tissue have identified putative causal genes by demonstrating a genetic overlap between gene regulation and AMD risk. Linking genetic data to complement measurements in the systemic circulation has aided in understanding the effect of AMD-associated genetic variants in the complement system, and supports that protein QTL (pQTL) studies in plasma or serum samples may aid in understanding the effect of genetic variants and pinpointing causal genes in AMD. A recent epigenomic study fine-mapped AMD causal variants by determing regulatory regions in RPE cells differentiated from induced pluripotent stem cells (iPSC-RPE). Another approach that is being employed to pinpoint causal AMD genes is to produce synthetic DNA assemblons representing risk and protective haplotypes, which are then delivered to cellular or animal model systems. Pinpointing causal genes and understanding disease mechanisms is crucial for the next step towards clinical translation. Clinical trials targeting proteins encoded by the AMD-associated genomic loci C3, CFB, CFI, CFH, and ARMS2/HTRA1 are currently ongoing, and a phase III clinical trial for C3 inhibition recently showed a modest reduction of lesion growth in geographic atrophy. The EYERISK consortium recently developed a genetic test for AMD that allows genotyping of common and rare variants in AMD-associated genes. Polygenic risk scores (PRS) were applied to quantify AMD genetic risk, and may aid in predicting AMD progression. In conclusion, genomic studies represent a turning point in our exploration of AMD. The results of those studies now serve as a driving force for several clinical trials. Expanding to omics and systems genomics will further decipher function and causality from the associations that have been reported, and will enable the development of therapies that will lessen the burden of AMD.


Asunto(s)
Degeneración Macular , Humanos , Degeneración Macular/genética , Degeneración Macular/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Proteínas del Sistema Complemento/metabolismo , Coroides/metabolismo , Proteínas/genética , Genómica , Polimorfismo de Nucleótido Simple , Factor H de Complemento/genética , Factor H de Complemento/metabolismo , Serina Peptidasa A1 que Requiere Temperaturas Altas/genética
4.
Int J Mol Sci ; 23(11)2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35682771

RESUMEN

Anti-VEGF treatment for neovascular age-related macular degeneration (nAMD) has been FDA-approved in 2004, and since then has helped tens of thousands of patients worldwide to preserve vision. Still, treatment responses vary widely, emphasizing the need for genetic biomarkers to robustly separate responders from non-responders. Here, we report the findings of an observational study compromising 179 treatment-naïve nAMD patients and their reaction to treatment after three monthly doses of anti-VEGF antibodies. We show that established criteria of treatment response such as visual acuity and central retinal thickness successfully divides our cohort into 128 responders and 51 non-responders. Nevertheless, retinal thickness around the fovea revealed significant reaction to treatment even in the formally categorized non-responders. To elucidate genetic effects underlying our criteria, we conducted an undirected genome-wide association study followed by a directed replication study of 30 previously reported genetic variants. Remarkably, both approaches failed to result in significant findings, suggesting study-specific effects were confounding the present and previous discovery studies. Of note, all studies so far are greatly underpowered, hampering interpretation of genetic findings. In consequence, we highlight the need for an extensive phenotyping study with sample sizes exceeding at least 15,000 to reliably assess anti-VEGF treatment responses in nAMD.


Asunto(s)
Estudio de Asociación del Genoma Completo , Degeneración Macular , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Humanos , Inyecciones Intravítreas , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/genética , Ranibizumab/uso terapéutico , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Factores de Crecimiento Endotelial Vascular
5.
Int J Mol Sci ; 21(8)2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32294914

RESUMEN

Choroidal neovascularization (CNV) is a pathological process in which aberrant blood vessels invade the subretinal space of the mammalian eye. It is a characteristic feature of the prevalent neovascular age-related macular degeneration (nAMD). Circulating microRNAs (cmiRNAs) are regarded as potentially valuable biomarkers for various age-related diseases, including nAMD. Here, we investigated cmiRNA expression in an established laser-induced CNV mouse model. Upon CNV induction in C57Bl/6 mice, blood-derived cmiRNAs were initially determined globally by RNA next generation sequencing, and the most strongly dysregulated cmiRNAs were independently replicated by quantitative reverse transcription PCR (RT-qPCR) in blood, retinal, and retinal pigment epithelium (RPE)/choroidal tissue. Our findings suggest that two miRNAs, mmu-mir-486a-5p and mmur-mir-92a-3p, are consistently dysregulated during CNV formation. Furthermore, in functional in vitro assays, a significant impact of mmu-mir-486a-5p and mmu-mir-92a-3p on murine microglial cell viability was observed, while mmu-mir-92a-3p also showed an impact on microglial mobility. Taken together, we report a robust dysregulation of two miRNAs in blood and RPE/choroid after laser-induced initiation of CNV lesions in mice, highlighting their potential role in pathology and eventual therapy of CNV-associated complications.


Asunto(s)
Neovascularización Coroidal/sangre , Neovascularización Coroidal/etiología , MicroARN Circulante/genética , Rayos Láser/efectos adversos , Animales , Células Cultivadas , Neovascularización Coroidal/metabolismo , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Células Endoteliales/metabolismo , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , MicroARNs/genética , Microglía/metabolismo , Retina/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Transcriptoma
6.
Nat Commun ; 15(1): 1972, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438351

RESUMEN

DNA methylation provides a crucial epigenetic mark linking genetic variations to environmental influence. We have analyzed array-based DNA methylation profiles of 160 human retinas with co-measured RNA-seq and >8 million genetic variants, uncovering sites of genetic regulation in cis (37,453 methylation quantitative trait loci and 12,505 expression quantitative trait loci) and 13,747 DNA methylation loci affecting gene expression, with over one-third specific to the retina. Methylation and expression quantitative trait loci show non-random distribution and enrichment of biological processes related to synapse, mitochondria, and catabolism. Summary data-based Mendelian randomization and colocalization analyses identify 87 target genes where methylation and gene-expression changes likely mediate the genotype effect on age-related macular degeneration. Integrated pathway analysis reveals epigenetic regulation of immune response and metabolism including the glutathione pathway and glycolysis. Our study thus defines key roles of genetic variations driving methylation changes, prioritizes epigenetic control of gene expression, and suggests frameworks for regulation of macular degeneration pathology by genotype-environment interaction in retina.


Asunto(s)
Metilación de ADN , Degeneración Macular , Humanos , Metilación de ADN/genética , Epigénesis Genética , Epigenoma , Degeneración Macular/genética , Retina
7.
Transl Vis Sci Technol ; 12(5): 17, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37191621

RESUMEN

Purpose: Anti-vascular endothelial growth factor (anti-VEGF) therapies, which attenuate the capacity of VEGF to bind to VEGF receptors, are standard-of-care options for various retinal disorders that are characterized by pathologic retinal angiogenesis and vascular permeability. Multiple receptors and ligands have also been reported as being involved in these pathways, including angiopoietin-1 (ANG1) and angiopoietin-2 (ANG2). Methods: Electrochemiluminescence immunoassays were used to detect human VEGF (hVEGF), as well as rabbit ANG2 and basic fibroblast growth factor protein levels in vitreous samples derived from a study evaluating the efficacy of the anti-VEGF agents ranibizumab, aflibercept, and brolucizumab in an hVEGF165-induced rabbit retinal vascular hyperpermeability model. Results: hVEGF was completely suppressed in rabbit vitreous after anti-VEGF treatment for 28 days. ANG2 protein in vitreous and ANGPT2 mRNA in retina tissue were similarly suppressed, although the anti-VEGF agents do not directly bind to ANG2. Aflibercept demonstrated the greatest inhibitory effect in ANG2 levels in vitreous, which correlated with strong, durable suppression of intraocular hVEGF levels. Conclusions: This study explored the effects of anti-VEGF therapies beyond direct binding of VEGF by evaluating protein levels and the expression of target genes involved in angiogenesis and associated molecular mechanisms in the rabbit retina and choroid. Translational Relevance: In vivo data suggest that anti-VEGF agents currently used for the treatment of retinal diseases could provide beneficial effects beyond direct binding of VEGF, including suppression of ANG2 protein and ANGPT2 mRNA.


Asunto(s)
Angiopoyetina 2 , Factor A de Crecimiento Endotelial Vascular , Animales , Conejos , Humanos , Factor A de Crecimiento Endotelial Vascular/genética , Angiopoyetina 2/genética , Angiopoyetina 2/metabolismo , Factores de Crecimiento Endotelial Vascular , Receptores de Factores de Crecimiento Endotelial Vascular , Neovascularización Patológica , ARN Mensajero/metabolismo
8.
Res Sq ; 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37398472

RESUMEN

DNA methylation (DNAm) provides a crucial epigenetic mark linking genetic variations to environmental influence. We analyzed array-based DNAm profiles of 160 human retinas with co-measured RNA-seq and > 8 million genetic variants, uncovering sites of genetic regulation in cis (37,453 mQTLs and 12,505 eQTLs) and 13,747 eQTMs (DNAm loci affecting gene expression), with over one-third specific to the retina. mQTLs and eQTMs show non-random distribution and enrichment of biological processes related to synapse, mitochondria, and catabolism. Summary data-based Mendelian randomization and colocalization analyses identify 87 target genes where methylation and gene-expression changes likely mediate the genotype effect on age-related macular degeneration (AMD). Integrated pathway analysis reveals epigenetic regulation of immune response and metabolism including the glutathione pathway and glycolysis. Our study thus defines key roles of genetic variations driving methylation changes, prioritizes epigenetic control of gene expression, and suggests frameworks for regulation of AMD pathology by genotype-environment interaction in retina.

9.
Cells ; 11(11)2022 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-35681461

RESUMEN

The pathogenesis of age-related macular degeneration (AMD), a frequent disorder of the central retina, is incompletely understood. Genome-wide association studies (GWAS) suggest a strong contribution of genomic variation in AMD susceptibility. Nevertheless, little is known about biological mechanisms of the disease. We reported previously that the AMD-associated polymorphism rs704C > T in the vitronectin (VTN) gene influences protein expression and functional aspects of encoded vitronectin, a human blood and extracellular matrix (ECM) protein. Here, we refined the association of rs704 with AMD in 16,144 cases and 17,832 controls and noted that rs704 is carried exclusively by the neovascular AMD subtype. Interaction studies demonstrate that rs704 affects the ability of vitronectin to bind the angiogenic regulator plasminogen activator inhibitor 1 (PAI-1) but has no influence on stabilizing its active state. Western blot analysis and confocal imaging reveal a strong enrichment of PAI-1 in the ECM of cultured endothelial cells and RPE cell line ARPE-19 exposed to vitronectin. Large-scale gene expression of VTN and PAI-1 showed positive correlations and a statistically significant increase in human retinal and blood tissues aged 60 years and older. Our results suggest a mechanism by which the AMD-associated rs704 variant in combination with ageing may contribute to the vascular complications in AMD.


Asunto(s)
Degeneración Macular , Inhibidor 1 de Activador Plasminogénico , Vitronectina , Anciano , Inhibidores de la Angiogénesis , Células Endoteliales , Estudio de Asociación del Genoma Completo , Humanos , Degeneración Macular/genética , Degeneración Macular/patología , Persona de Mediana Edad , Inhibidor 1 de Activador Plasminogénico/genética , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual , Vitronectina/genética
10.
Cells ; 10(9)2021 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-34572044

RESUMEN

Elucidating the role of genetic variation in the regulation of gene expression is key to understanding the pathobiology of complex diseases which, in consequence, is crucial in devising targeted treatment options. Expression quantitative trait locus (eQTL) analysis correlates a genetic variant with the strength of gene expression, thus defining thousands of regulated genes in a multitude of human cell types and tissues. Some eQTL may not act independently of each other but instead may be regulated in a coordinated fashion by seemingly independent genetic variants. To address this issue, we combined the approaches of eQTL analysis and colocalization studies. Gene expression was determined in datasets comprising 49 tissues from the Genotype-Tissue Expression (GTEx) project. From about 33,000 regulated genes, over 14,000 were found to be co-regulated in pairs and were assembled across all tissues to almost 15,000 unique clusters containing up to nine regulated genes affected by the same eQTL signal. The distance of co-regulated eGenes was, on average, 112 kilobase pairs. Of 713 genes known to express clinical symptoms upon haploinsufficiency, 231 (32.4%) are part of at least one of the identified clusters. This calls for caution should treatment approaches aim at an upregulation of a haploinsufficient gene. In conclusion, we present an unbiased approach to identifying co-regulated genes in and across multiple tissues. Knowledge of such common effects is crucial to appreciate implications on biological pathways involved, specifically when a treatment option targets a co-regulated disease gene.


Asunto(s)
Biología Computacional/métodos , Genes Reguladores , Predisposición Genética a la Enfermedad , Familia de Multigenes , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Perfilación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Humanos
11.
Sci Rep ; 11(1): 13114, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34162900

RESUMEN

The currently largest genome-wide association study (GWAS) for age-related macular degeneration (AMD) defines disease association with genome-wide significance for 52 independent common and rare genetic variants across 34 chromosomal loci. Overall, these loci contain over 7200 variants and are enriched for genes with functions indicating several shared cellular processes. Still, the precise mechanisms leading to AMD pathology are largely unknown. Here, we exploit the phenomenon of epistatic interaction to identify seemingly independent AMD-associated variants that reveal joint effects on gene expression. We focus on genetic variants associated with lipid metabolism, organization of extracellular structures, and innate immunity, specifically the complement cascade. Multiple combinations of independent variants were used to generate genetic risk scores allowing gene expression in liver to be compared between low and high-risk AMD. We identified genetic variant combinations correlating significantly with expression of 26 genes, of which 19 have not been associated with AMD before. This study defines novel targets and allows prioritizing further functional work into AMD pathobiology.


Asunto(s)
Epistasis Genética/genética , Sitios Genéticos/genética , Degeneración Macular/genética , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Ligasas de Carbono-Nitrógeno con Glutamina como Donante de Amida-N/genética , Ligasas de Carbono-Nitrógeno con Glutamina como Donante de Amida-N/metabolismo , Vía Clásica del Complemento/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulación de la Expresión Génica , Variación Genética/genética , Humanos , Metabolismo de los Lípidos/genética , Hígado/metabolismo
12.
Cells ; 9(10)2020 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-33050031

RESUMEN

Genome-wide association studies (GWAS) have identified an abundance of genetic loci associated with complex traits and diseases. In contrast, in-depth characterization of an individual genetic signal is rarely available. Here, we focus on the genetic variant rs2168518 in 15q24.1 previously associated with age-related macular degeneration (AMD), but only with suggestive evidence. In a two-step procedure, we initially conducted a series of association analyses to further delineate the association of rs2168518 with AMD but also with other complex phenotypes by using large independent datasets from the International AMD Genomics Consortium (IAMDGC) and the UK Biobank. We then performed a functional annotation with reference to gene expression regulation based on data from the Genotype-Tissue Expression (GTEx) project and RegulomeDB. Association analysis revealed a gender-specific association with male AMD patients and an association predominantly with choroidal neovascularization. Further, the AMD association colocalizes with an association signal of several blood pressure-related phenotypes and with the gene expression regulation of CYP1A1, a member of the cytochrome P450 superfamily of monooxygenases. Functional annotation revealed altered transcription factor (TF) binding sites for gender-specific TFs, including SOX9 and SRY. In conclusion, the pleiotropic 15q24.1 association signal suggests a shared mechanism between blood pressure regulation and choroidal neovascularization with a potential involvement of CYP1A1.


Asunto(s)
Degeneración Macular/genética , MicroARNs/genética , Neovascularización Coroidal/genética , Neovascularización Coroidal/metabolismo , Cromosomas Humanos Par 15/genética , Bases de Datos Genéticas , Femenino , Sitios Genéticos/genética , Pleiotropía Genética/genética , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo/métodos , Humanos , Masculino , MicroARNs/metabolismo , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales
13.
Cells ; 9(10)2020 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-33050425

RESUMEN

Over the last 15 years, genome-wide association studies (GWAS) have greatly advanced our understanding of the genetic landscape of complex phenotypes. Nevertheless, causal interpretations of GWAS data are challenging but crucial to understand underlying mechanisms and pathologies. In this review, we explore to what extend the research community follows up on GWAS data. We have traced the scientific activities responding to the two largest GWAS conducted on age-related macular degeneration (AMD) so far. Altogether 703 articles were manually categorized according to their study type. This demonstrates that follow-up studies mainly involve "Review articles" (33%) or "Genetic association studies" (33%), while 19% of publications report on findings from experimental work. It is striking to note that only three of 16 AMD-associated loci described de novo in 2016 were examined in the four-year follow-up period after publication. A comparative analysis of five studies on gene expression regulation in AMD-associated loci revealed consistent gene candidates for 15 of these loci. Our random survey highlights the fact that functional follow-up studies on GWAS results are still in its early stages hampering a significant refinement of the vast association data and thus a more accurate insight into mechanisms and pathways.


Asunto(s)
Estudio de Asociación del Genoma Completo/tendencias , Degeneración Macular/genética , Bases de Datos Genéticas , Expresión Génica/genética , Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Fenotipo , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Transcriptoma/genética
14.
Sci Rep ; 10(1): 1584, 2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-32005911

RESUMEN

Genome-wide association studies (GWAS) for late stage age-related macular degeneration (AMD) have identified 52 independent genetic variants with genome-wide significance at 34 genomic loci. Typically, such an approach rarely results in the identification of functional variants implicating a defined gene in the disease process. We now performed a transcriptome-wide association study (TWAS) allowing the prediction of effects of AMD-associated genetic variants on gene expression. The TWAS was based on the genotypes of 16,144 late-stage AMD cases and 17,832 healthy controls, and gene expression was imputed for 27 different human tissues which were obtained from 134 to 421 individuals. A linear regression model including each individuals imputed gene expression data and the respective AMD status identified 106 genes significantly associated to AMD variants in at least one tissue (Q-value < 0.001). Gene enrichment analysis highlighted rather systemic than tissue- or cell-specific processes. Remarkably, 31 of the 106 genes overlapped with significant GWAS signals of other complex traits and diseases, such as neurological or autoimmune conditions. Taken together, our study highlights the fact that expression of genes associated with AMD is not restricted to retinal tissue as could be expected for an eye disease of the posterior pole, but instead is rather ubiquitous suggesting processes underlying AMD pathology to be of systemic nature.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Degeneración Macular/genética , Transcriptoma/genética , Perfilación de la Expresión Génica , Redes Reguladoras de Genes/genética , Genes/genética , Estudio de Asociación del Genoma Completo , Humanos
15.
BMC Med Genomics ; 13(1): 120, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-32843070

RESUMEN

BACKGROUND: Advanced age-related macular degeneration (AMD) is a leading cause of blindness. While around half of the genetic contribution to advanced AMD has been uncovered, little is known about the genetic architecture of early AMD. METHODS: To identify genetic factors for early AMD, we conducted a genome-wide association study (GWAS) meta-analysis (14,034 cases, 91,214 controls, 11 sources of data including the International AMD Genomics Consortium, IAMDGC, and UK Biobank, UKBB). We ascertained early AMD via color fundus photographs by manual grading for 10 sources and via an automated machine learning approach for > 170,000 photographs from UKBB. We searched for early AMD loci via GWAS and via a candidate approach based on 14 previously suggested early AMD variants. RESULTS: Altogether, we identified 10 independent loci with statistical significance for early AMD: (i) 8 from our GWAS with genome-wide significance (P < 5 × 10- 8), (ii) one previously suggested locus with experiment-wise significance (P < 0.05/14) in our non-overlapping data and with genome-wide significance when combining the reported and our non-overlapping data (together 17,539 cases, 105,395 controls), and (iii) one further previously suggested locus with experiment-wise significance in our non-overlapping data. Of these 10 identified loci, 8 were novel and 2 known for early AMD. Most of the 10 loci overlapped with known advanced AMD loci (near ARMS2/HTRA1, CFH, C2, C3, CETP, TNFRSF10A, VEGFA, APOE), except two that have not yet been identified with statistical significance for any AMD. Among the 17 genes within these two loci, in-silico functional annotation suggested CD46 and TYR as the most likely responsible genes. Presence or absence of an early AMD effect distinguished the known pathways of advanced AMD genetics (complement/lipid pathways versus extracellular matrix metabolism). CONCLUSIONS: Our GWAS on early AMD identified novel loci, highlighted shared and distinct genetics between early and advanced AMD and provides insights into AMD etiology. Our data provide a resource comparable in size to the existing IAMDGC data on advanced AMD genetics enabling a joint view. The biological relevance of this joint view is underscored by the ability of early AMD effects to differentiate the major pathways for advanced AMD.


Asunto(s)
Sitios Genéticos , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Degeneración Macular/genética , Degeneración Macular/patología , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Humanos
17.
Sci Rep ; 8(1): 5865, 2018 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-29650998

RESUMEN

Genome-wide association studies (GWAS) have identified numerous genetic variants in the human genome associated with diseases and traits. Nevertheless, for most loci the causative variant is still unknown. Expression quantitative trait loci (eQTL) in disease relevant tissues is an excellent approach to correlate genetic association with gene expression. While liver is the primary site of gene transcription for two pathways relevant to age-related macular degeneration (AMD), namely the complement system and cholesterol metabolism, we explored the contribution of AMD associated variants to modulate liver gene expression. We extracted publicly available data and computed the largest eQTL data set for liver tissue to date. Genotypes and expression data from all studies underwent rigorous quality control. Subsequently, Matrix eQTL was used to identify significant local eQTL. In total, liver samples from 588 individuals revealed 202,489 significant eQTL variants affecting 1,959 genes (Q-Value < 0.001). In addition, a further 101 independent eQTL signals were identified in 93 of the 1,959 eQTL genes. Importantly, our results independently reinforce the notion that high density lipoprotein metabolism plays a role in AMD pathogenesis. Taken together, our study generated a first comprehensive map reflecting the genetic regulatory landscape of gene expression in liver.


Asunto(s)
Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad , Degeneración Macular/genética , Sitios de Carácter Cuantitativo/genética , Genoma Humano/genética , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Hígado/metabolismo , Degeneración Macular/patología , Fenotipo , Polimorfismo de Nucleótido Simple
18.
Invest Ophthalmol Vis Sci ; 57(6): 2463-71, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-27149696

RESUMEN

PURPOSE: To genetically characterize a subphenotype of geographic atrophy (GA) in AMD associated with rapid progression and a diffuse-trickling appearance on fundus autofluorescence imaging. METHODS: Patients from the Fundus Autofluorescence in Age-Related Macular Degeneration Study were phenotyped for diffuse-trickling GA (dt-GA; n = 44). DNA was analyzed for 10 known AMD-associated genetic variants. A genetic risk score (GRS) was calculated and compared with patients with nondiffuse-trickling GA (ndt-GA; n = 311) and individuals from the 1000 genomes project (1000G; n = 267). Given the phenotypic overlap between diffuse-trickling and late-onset retinal degeneration (LORD), all C1QTNF5 exons and their exon/intron boundaries were sequenced. RESULTS: A statistically significant difference in allele frequencies between dt-GA and ndt-GA were found for CFH:rs1061170 and CFH:rs800292 (Pcorrected = 0.03). The ARMS2 variant rs10490924 was significantly more frequent in dt-GA than in 1000G individuals (Pcorrected < 0.01). The GRS of dt-GA patients was in-between the score of the 1000G individuals and that of patients with ndt-GA, significantly differing from both (Pcorrected <0.01). Sequencing of C1QTNF5 revealed 28 unique variants although none showed a statistically significant association with dt-GA when compared with 1000G individuals. CONCLUSIONS: The dt-GA phenotype shows a remarkably different genetic risk profile from other GA phenotypes secondary to AMD. Disease-associated C1QTNF5 mutations were not identified. Together, these results suggest that the dt-GA phenotype is associated with a genetic background substantially different from other GA phenotypes and underlines the necessity to refine the clinical phenotyping, specifically when aiming for individualized therapies in AMD.


Asunto(s)
Colágeno/genética , ADN/genética , Atrofia Geográfica/genética , Degeneración Macular/genética , Mutación , Anciano , Colágeno/metabolismo , Análisis Mutacional de ADN , Exones , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Frecuencia de los Genes , Genotipo , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/etiología , Humanos , Degeneración Macular/complicaciones , Degeneración Macular/diagnóstico , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tomografía de Coherencia Óptica
19.
PLoS One ; 10(5): e0126636, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25962167

RESUMEN

Worldwide, age-related macular degeneration (AMD) is a serious threat to vision loss in individuals over 50 years of age with a pooled prevalence of approximately 9%. For 2020, the number of people afflicted with this condition is estimated to reach 200 million. While AMD lesions presenting as geographic atrophy (GA) show high inter-individual variability, only little is known about prognostic factors. Here, we aimed to elucidate the contribution of clinical, demographic and genetic factors on GA progression. Analyzing the currently largest dataset on GA lesion growth (N = 388), our findings suggest a significant and independent contribution of three factors on GA lesion growth including at least two genetic factors (ARMS2_rs10490924 [P < 0.00088] and C3_rs2230199 [P < 0.00015]) as well as one clinical component (presence of GA in the fellow eye [P < 0.00023]). These correlations jointly explain up to 7.2% of the observed inter-individual variance in GA lesion progression and should be considered in strategy planning of interventional clinical trials aimed at evaluating novel treatment options in advanced GA due to AMD.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/genética , Anciano , Anciano de 80 o más Años , Alelos , Progresión de la Enfermedad , Angiografía con Fluoresceína , Estudios de Seguimiento , Genotipo , Humanos , Proteínas/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA