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Brock DC, Wang M, Hussain HMJ, Rauch DE, Marra M, Pennesi ME, Yang P, Everett L, Ajlan RS, Colbert J, Porto FBO, Matynia A, Gorin MB, Koenekoop RK, Lopez I, Sui R, Zou G, Li Y, Chen R. Comparative analysis of in-silico tools in identifying pathogenic variants in dominant inherited retinal diseases. Hum Mol Genet 2024; 33:945-957. [PMID: 38453143 PMCID: PMC11102593 DOI: 10.1093/hmg/ddae028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 03/09/2024] Open
Abstract
Inherited retinal diseases (IRDs) are a group of rare genetic eye conditions that cause blindness. Despite progress in identifying genes associated with IRDs, improvements are necessary for classifying rare autosomal dominant (AD) disorders. AD diseases are highly heterogenous, with causal variants being restricted to specific amino acid changes within certain protein domains, making AD conditions difficult to classify. Here, we aim to determine the top-performing in-silico tools for predicting the pathogenicity of AD IRD variants. We annotated variants from ClinVar and benchmarked 39 variant classifier tools on IRD genes, split by inheritance pattern. Using area-under-the-curve (AUC) analysis, we determined the top-performing tools and defined thresholds for variant pathogenicity. Top-performing tools were assessed using genome sequencing on a cohort of participants with IRDs of unknown etiology. MutScore achieved the highest accuracy within AD genes, yielding an AUC of 0.969. When filtering for AD gain-of-function and dominant negative variants, BayesDel had the highest accuracy with an AUC of 0.997. Five participants with variants in NR2E3, RHO, GUCA1A, and GUCY2D were confirmed to have dominantly inherited disease based on pedigree, phenotype, and segregation analysis. We identified two uncharacterized variants in GUCA1A (c.428T>A, p.Ile143Thr) and RHO (c.631C>G, p.His211Asp) in three participants. Our findings support using a multi-classifier approach comprised of new missense classifier tools to identify pathogenic variants in participants with AD IRDs. Our results provide a foundation for improved genetic diagnosis for people with IRDs.
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Affiliation(s)
- Daniel C Brock
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
- Medical Scientist Training Program, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
| | - Meng Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
| | - Hafiz Muhammad Jafar Hussain
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
| | - David E Rauch
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
| | - Molly Marra
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR 97239, United States
| | - Mark E Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR 97239, United States
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR 97239, United States
| | - Lesley Everett
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, 515 SW Campus Drive, Portland, OR 97239, United States
| | - Radwan S Ajlan
- Department of Ophthalmology, University of Kansas School of Medicine, 3901 Rainbow Blvd, Kansas City, KS 66160, United States
| | - Jason Colbert
- Department of Ophthalmology, University of Kansas School of Medicine, 3901 Rainbow Blvd, Kansas City, KS 66160, United States
| | - Fernanda Belga Ottoni Porto
- INRET Clínica e Centro de Pesquisa, Rua dos Otoni, 735/507 - Santa Efigênia, Belo Horizonte, MG 30150270, Brazil
- Department of Ophthalmology, Santa Casa de Misericórdia de Belo Horizonte, Av. Francisco Sales, 1111 - Santa Efigênia, Belo Horizonte, MG 30150221, Brazil
- Centro Oftalmológico de Minas Gerais, R. Santa Catarina, 941 - Lourdes, Belo Horizonte, MG 30180070, Brazil
| | - Anna Matynia
- College of Optometry, University of Houston, 4401 Martin Luther King Boulevard, Houston, TX 77004, United States
| | - Michael B Gorin
- Jules Stein Eye Institute, University of California Los Angeles, 100 Stein Plaza, Los Angeles, CA 90095, United States
- Department of Ophthalmology, University of California Los Angeles David Geffen School of Medicine, 10833 Le Conte Ave, Los Angeles, CA 90095, United States
| | - Robert K Koenekoop
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, 5252 Boul de Maisonneuve ouest, Montreal, QC H4A 3S5, Canada
| | - Irma Lopez
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, 5252 Boul de Maisonneuve ouest, Montreal, QC H4A 3S5, Canada
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, WC67+HW Dongcheng, Beijing 100005, China
| | - Gang Zou
- Department of Ophthalmology, Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region, First Affiliated Hospital of Northwest University for Nationalities, Ningxia Clinical Research Center on Diseases of Blindness in Eye, F4RJ+43 Xixia District, Yinchuan, Ningxia, China
| | - Yumei Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
- Human Genome Sequencing Center, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
| | - Rui Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
- Human Genome Sequencing Center, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States
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Gocuk SA, Edwards TL, Jolly JK, Ayton LN. Perspectives of carriers of X-linked retinal diseases on genetic testing and gene therapy: A global survey. Clin Genet 2024; 105:150-158. [PMID: 37859457 DOI: 10.1111/cge.14442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/03/2023] [Accepted: 10/06/2023] [Indexed: 10/21/2023]
Abstract
Female carriers of X-linked inherited retinal diseases (IRDs) are burdened with potentially passing their disease-causing variant to future generations, as well as exhibiting signs of retinal disease themselves. This study aimed to investigate carriers' experiences of genetic testing, emotions relating to having affected children, and their knowledge regarding genetic testing and gene therapy. An online survey was advertised to self-identified carriers worldwide. Two hundred and twenty-eight carriers completed the survey with mean age of 51 years (SD ± 15.0). A majority of respondents resided in the United States of America (51%), Australia (19%), and the United Kingdom (14%). Most carriers identified with feelings of guilt (70%), concern (91%), and anxiety (88%) for their child. Female carriers who had given birth to children had significantly greater gene therapy knowledge compared to carriers who had not (p < 0.05). Respondents agreed that their eyecare provider and general practitioner helped them understand their condition (63%), however, few carriers reported receiving psychological counselling (9%) or family planning advice (5%). Most respondents (78%) agreed that gene therapy should be available to carriers. This study emphasises the importance of providing appropriate counselling to female carriers and illustrates the motivation of many to participate in emerging treatment options, such as gene therapy.
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Affiliation(s)
- Sena A Gocuk
- Department of Optometry and Vision Sciences, University of Melbourne, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Thomas L Edwards
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
| | - Jasleen K Jolly
- Vision and Eye Research Institute, Anglia Ruskin University, Cambridge, UK
| | - Lauren N Ayton
- Department of Optometry and Vision Sciences, University of Melbourne, Melbourne, Victoria, Australia
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia
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Dueñas Rey A, Del Pozo Valero M, Bouckaert M, Wood KA, Van den Broeck F, Daich Varela M, Thomas HB, Van Heetvelde M, De Bruyne M, Van de Sompele S, Bauwens M, Lenaerts H, Mahieu Q, Josifova D, Rivolta C, O'Keefe RT, Ellingford J, Webster AR, Arno G, Ayuso C, De Zaeytijd J, Leroy BP, De Baere E, Coppieters F. Combining a prioritization strategy and functional studies nominates 5'UTR variants underlying inherited retinal disease. Genome Med 2024; 16:7. [PMID: 38184646 PMCID: PMC10771650 DOI: 10.1186/s13073-023-01277-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 12/15/2023] [Indexed: 01/08/2024] Open
Abstract
BACKGROUND 5' untranslated regions (5'UTRs) are essential modulators of protein translation. Predicting the impact of 5'UTR variants is challenging and rarely performed in routine diagnostics. Here, we present a combined approach of a comprehensive prioritization strategy and functional assays to evaluate 5'UTR variation in two large cohorts of patients with inherited retinal diseases (IRDs). METHODS We performed an isoform-level re-analysis of retinal RNA-seq data to identify the protein-coding transcripts of 378 IRD genes with highest expression in retina. We evaluated the coverage of their 5'UTRs by different whole exome sequencing (WES) kits. The selected 5'UTRs were analyzed in whole genome sequencing (WGS) and WES data from IRD sub-cohorts from the 100,000 Genomes Project (n = 2397 WGS) and an in-house database (n = 1682 WES), respectively. Identified variants were annotated for 5'UTR-relevant features and classified into seven categories based on their predicted functional consequence. We developed a variant prioritization strategy by integrating population frequency, specific criteria for each category, and family and phenotypic data. A selection of candidate variants underwent functional validation using diverse approaches. RESULTS Isoform-level re-quantification of retinal gene expression revealed 76 IRD genes with a non-canonical retina-enriched isoform, of which 20 display a fully distinct 5'UTR compared to that of their canonical isoform. Depending on the probe design, 3-20% of IRD genes have 5'UTRs fully captured by WES. After analyzing these regions in both cohorts, we prioritized 11 (likely) pathogenic variants in 10 genes (ARL3, MERTK, NDP, NMNAT1, NPHP4, PAX6, PRPF31, PRPF4, RDH12, RD3), of which 7 were novel. Functional analyses further supported the pathogenicity of three variants. Mis-splicing was demonstrated for the PRPF31:c.-9+1G>T variant. The MERTK:c.-125G>A variant, overlapping a transcriptional start site, was shown to significantly reduce both luciferase mRNA levels and activity. The RDH12:c.-123C>T variant was found in cis with the hypomorphic RDH12:c.701G>A (p.Arg234His) variant in 11 patients. This 5'UTR variant, predicted to introduce an upstream open reading frame, was shown to result in reduced RDH12 protein but unaltered mRNA levels. CONCLUSIONS This study demonstrates the importance of 5'UTR variants implicated in IRDs and provides a systematic approach for 5'UTR annotation and validation that is applicable to other inherited diseases.
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Affiliation(s)
- Alfredo Dueñas Rey
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Marta Del Pozo Valero
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
- Department of Genetics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
| | - Manon Bouckaert
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Katherine A Wood
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester, UK
| | - Filip Van den Broeck
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
- Department of Head & Skin, Ghent University, Ghent, Belgium
| | - Malena Daich Varela
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Huw B Thomas
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester, UK
| | - Mattias Van Heetvelde
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Marieke De Bruyne
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Stijn Van de Sompele
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Miriam Bauwens
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Hanne Lenaerts
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Quinten Mahieu
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | | | - Carlo Rivolta
- Department of Ophthalmology, University of Basel, Basel, Switzerland
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Raymond T O'Keefe
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester, UK
| | - Jamie Ellingford
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester, UK
- Genomics England, London, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester, UK
| | - Andrew R Webster
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Gavin Arno
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Carmen Ayuso
- Department of Genetics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Julie De Zaeytijd
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
- Department of Head & Skin, Ghent University, Ghent, Belgium
| | - Bart P Leroy
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
- Department of Head & Skin, Ghent University, Ghent, Belgium
- Division of Ophthalmology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Elfride De Baere
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium
| | - Frauke Coppieters
- Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Ghent, Belgium.
- Department of Biomolecular Medicine, Ghent University, Corneel Heymanslaan 10, Ghent, 9000, Belgium.
- Department of Pharmaceutics, Ghent University, Ghent, Belgium.
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Künzel SH, Mahren E, Morr M, Holz FG, Lorenz B. [Diagnostics and management of patients with inherited retinal diseases in Germany : Results of a nationwide survey of university and non-university eye departments and specialized practices]. DIE OPHTHALMOLOGIE 2023; 120:1127-1137. [PMID: 37582888 DOI: 10.1007/s00347-023-01902-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/06/2023] [Accepted: 07/13/2023] [Indexed: 08/17/2023]
Abstract
BACKGROUND Inherited retinal diseases (IRDs) refer to a heterogeneous group of rare disorders that potentially lead to blindness. Emerging therapeutic options have led to a growing interest in IRDs; however, there are insufficient systematic studies on IRDs in Germany characterizing the demographics and management in clinical practice. OBJECTIVE To characterize the care for IRD patients in Germany, to assess the applied diagnostics, the use of databases and the implementation of education in ophthalmic genetics. METHODS The anonymous online survey (SoSci Survey GmbH) was sent to all German ophthalmology departments listed on the website of the German Ophthalmological Society and to three practices focusing on IRDs. RESULTS The overall response rate was 44.8%. Almost all institutions (93.6%) reported seeing IRD patients, but university and non-university hospitals differed in the number of patients. Databases are used in 60% of universities but only in 5.9% of non-university hospitals. Regarding the number of patients with genetic diagnostics, 53% of the non-university and 12% of the university sites reported that 20% at most of their patients had received a molecular genetic diagnosis. The results of the IRD practices are comparable with the university hospitals. Patients with biallelic RPE65 mutations-associated IRD, potential candidates for treatment with voretigene neparvovec (Luxturna®), were followed in 9/25 participating university departments. CONCLUSION This survey highlights the deficits in the management of IRD patients. In particular, we found a clear difference between university and non-university hospitals in the rate of patients with known molecular genetic results. Improvements should be initiated in the latter, especially because of existing and emerging therapeutic options.
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Affiliation(s)
- Sandrine H Künzel
- Klinik für Augenheilkunde, Universitätsklinikum Bonn, Ernst-Abbe Str. 2, 53127, Bonn, Deutschland
| | - Elias Mahren
- Klinik für Augenheilkunde, Universitätsklinikum Bonn, Ernst-Abbe Str. 2, 53127, Bonn, Deutschland
| | - Mitjan Morr
- Sektion für Medizinische Psychologie, Klinik und Poliklinik für Psychiatrie und Psychotherapie, Universitätsklinikum Bonn, Bonn, Deutschland
| | - Frank G Holz
- Klinik für Augenheilkunde, Universitätsklinikum Bonn, Ernst-Abbe Str. 2, 53127, Bonn, Deutschland
| | - Birgit Lorenz
- Klinik für Augenheilkunde, Universitätsklinikum Bonn, Ernst-Abbe Str. 2, 53127, Bonn, Deutschland.
- Justus-Liebig-Universität Gießen, Gießen, Deutschland.
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Marwan M, Dawood M, Ullah M, Shah IU, Khan N, Hassan MT, Karam M, Rawlins LE, Baple EL, Crosby AH, Saleha S. Unravelling the genetic basis of retinal dystrophies in Pakistani consanguineous families. BMC Ophthalmol 2023; 23:205. [PMID: 37165311 PMCID: PMC10170854 DOI: 10.1186/s12886-023-02948-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 04/26/2023] [Indexed: 05/12/2023] Open
Abstract
BACKGROUND Retinitis Pigmentosa (RP) is a clinically and genetically progressive retinal dystrophy associated with severe visual impairments and sometimes blindness, the most common syndromic form of which is Usher syndrome (USH). This study aimed to further increase understanding of the spectrum of RP in the Khyber Pakhtunkhwa region of Pakistan. METHODOLOGY Four consanguineous families of Pashtun ethnic group were investigated which were referred by the local collaborating ophthalmologists. In total 42 individuals in four families were recruited and investigated using whole exome and dideoxy sequencing. Among them, 20 were affected individuals including 6 in both family 1 and 2, 5 in family 3 and 3 in family 4. RESULT Pathogenic gene variants were identified in all four families, including two in cone dystrophy and RP genes in the same family (PDE6C; c.480delG, p.Asn161ThrfsTer33 and TULP1; c.238 C > T, p.Gln80Ter) with double-homozygous individuals presenting with more severe disease. Other pathogenic variants were identified in MERTK (c.2194C > T, p.Arg732Ter), RHO (c.448G > A, p.Glu150Lys) associated with non-syndromic RP, and MYO7A (c.487G > A, p.Gly163Arg) associated with USH. In addition, the reported variants were of clinical significance as the PDE6C variant was detected novel, whereas TULP1, MERTK, and MYO7A variants were detected rare and first time found segregating with retinal dystrophies in Pakistani consanguineous families. CONCLUSIONS This study increases knowledge of the genetic basis of retinal dystrophies in families from Pakistan providing information important for genetic testing and diagnostic provision particularly from the Khyber Pakhtunkhwa region.
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Affiliation(s)
- Muhammad Marwan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Dawood
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Mukhtar Ullah
- Institute of Molecular and Clinical Ophthalmology Basel, Basel, 4031, Switzerland
- Department of Ophthalmology, University of Basel, Basel, 4056, Switzerland
| | - Irfan Ullah Shah
- Department of Ophthalmology, KMU Institute of Medical Sciences KIMS, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Niamat Khan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Taimur Hassan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Karam
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Lettie E Rawlins
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, UK
| | - Emma L Baple
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Andrew H Crosby
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Shamim Saleha
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, 26000, Pakistan.
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Hussain HMJ, Wang M, Huang A, Schmidt R, Qian X, Yang P, Marra M, Li Y, Pennesi ME, Chen R. Novel Pathogenic Mutations Identified from Whole-Genome Sequencing in Unsolved Cases of Patients Affected with Inherited Retinal Diseases. Genes (Basel) 2023; 14:447. [PMID: 36833373 PMCID: PMC9956865 DOI: 10.3390/genes14020447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 01/31/2023] [Accepted: 02/03/2023] [Indexed: 02/12/2023] Open
Abstract
Inherited retinal diseases (IRDs) are a diverse set of visual disorders that collectively represent a major cause of early-onset blindness. With the reduction in sequencing costs in recent years, whole-genome sequencing (WGS) is being used more frequently, particularly when targeted gene panels and whole-exome sequencing (WES) fail to detect pathogenic mutations in patients. In this study, we performed mutation screens using WGS for a cohort of 311 IRD patients whose mutations were undetermined. A total of nine putative pathogenic mutations in six IRD patients were identified, including six novel mutations. Among them, four were deep intronic mutations that affected mRNA splicing, while the other five affected protein-coding sequences. Our results suggested that the rate of resolution of unsolved cases via targeted gene panels and WES can be further enhanced with WGS; however, the overall improvement may be limited.
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Affiliation(s)
- Hafiz Muhammad Jafar Hussain
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meng Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Austin Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ryan Schmidt
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Xinye Qian
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Molly Marra
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Yumei Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mark E. Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Rui Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
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Mc Clinton B, Corradi Z, McKibbin M, Panneman DM, Roosing S, Boonen EGM, Ali M, Watson CM, Steel DH, Cremers FPM, Inglehearn CF, Hitti-Malin RJ, Toomes C. Effective smMIPs-Based Sequencing of Maculopathy-Associated Genes in Stargardt Disease Cases and Allied Maculopathies from the UK. Genes (Basel) 2023; 14:191. [PMID: 36672932 PMCID: PMC9859292 DOI: 10.3390/genes14010191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/06/2023] [Accepted: 01/07/2023] [Indexed: 01/13/2023] Open
Abstract
Macular dystrophies are a group of individually rare but collectively common inherited retinal dystrophies characterised by central vision loss and loss of visual acuity. Single molecule Molecular Inversion Probes (smMIPs) have proved effective in identifying genetic variants causing macular dystrophy. Here, a previously established smMIPs panel tailored for genes associated with macular diseases has been used to examine 57 UK macular dystrophy cases, achieving a high solve rate of 63.2% (36/57). Among 27 bi-allelic STGD1 cases, only three novel ABCA4 variants were identified, illustrating that the majority of ABCA4 variants in Caucasian STGD1 cases are currently known. We examined cases with ABCA4-associated disease in detail, comparing our results with a previously reported variant grading system, and found this model to be accurate and clinically useful. In this study, we showed that ABCA4-associated disease could be distinguished from other forms of macular dystrophy based on clinical evaluation in the majority of cases (34/36).
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Affiliation(s)
- Benjamin Mc Clinton
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
| | - Zelia Corradi
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Martin McKibbin
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
- Department of Ophthalmology, St. James’s University Hospital, Leeds LS9 7TF, UK
| | - Daan M. Panneman
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Erica G. M. Boonen
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Manir Ali
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
| | - Christopher M. Watson
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
- North East and Yorkshire Genomic Laboratory Hub, Central Lab, St. James’s University Hospital, Leeds LS9 7TF, UK
| | - David H. Steel
- Sunderland Eye Infirmary, Sunderland SR2 9HP, UK
- The Bioscience Institute, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Frans P. M. Cremers
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Chris F. Inglehearn
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
| | - Rebekkah J. Hitti-Malin
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Carmel Toomes
- Leeds Institute of Medical Research, University of Leeds, St James’s University Hospital, Leeds LS9 7TF, UK
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8
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The Diagnostic Yield of Next Generation Sequencing in Inherited Retinal Diseases: A Systematic Review and Meta-analysis. Am J Ophthalmol 2022; 249:57-73. [PMID: 36592879 DOI: 10.1016/j.ajo.2022.12.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/16/2022] [Accepted: 12/23/2022] [Indexed: 01/01/2023]
Abstract
PURPOSE Accurate genotyping of individuals with inherited retinal diseases (IRD) is essential for patient management and identifying suitable candidates for gene therapies. This study evaluated the diagnostic yield of next generation sequencing (NGS) in IRDs. DESIGN Systematic review and meta-analysis. METHODS This systematic review was prospectively registered (CRD42021293619). Ovid MEDLINE and Ovid Embase were searched on 6 June 2022. Clinical studies evaluating the diagnostic yield of NGS in individuals with IRDs were eligible for inclusion. Risk of bias assessment was performed. Studies were pooled using a random...effects inverse variance model. Sources of heterogeneity were explored using stratified analysis, meta-regression, and sensitivity analysis. RESULTS This study included 105 publications from 28 countries. Most studies (90 studies) used targeted gene panels. The diagnostic yield of NGS was 61.3% (95% confidence interval: 57.8-64.7%; 51 studies) in mixed IRD phenotypes, 58.2% (51.6-64.6%; 41 studies) in rod-cone dystrophies, 57.7% (46.8-68.3%; eight studies) in macular and cone/cone-rod dystrophies, and 47.6% (95% CI: 41.0-54.3%; four studies) in familial exudative vitreoretinopathy. For mixed IRD phenotypes, a higher diagnostic yield was achieved pooling studies published between 2018-2022 (64.2% [59.5-68.7%]), studies using exome sequencing (73.5% [58.9-86.1%]), and studies using the American College of Medical Genetics variant interpretation standards (65.6% [60.8-70.4%]). CONCLUSION The current diagnostic yield of NGS in IRDs is between 52-74%. The certainty of the evidence was judged as low or very low. A key limitation of the current evidence is the significant heterogeneity between studies. Adoption of standardized reporting guidelines could improve confidence in future meta-analyses.
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9
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Lynn J, Raney A, Britton N, Ramoin J, Yang RW, Radojevic B, McClard CK, Kingsley R, Coussa RG, Bennett LD. Genetic Diagnosis for 64 Patients with Inherited Retinal Disease. Genes (Basel) 2022; 14:74. [PMID: 36672815 PMCID: PMC9859429 DOI: 10.3390/genes14010074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/07/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
The overlapping genetic and clinical spectrum in inherited retinal degeneration (IRD) creates challenges for accurate diagnoses. The goal of this work was to determine the genetic diagnosis and clinical features for patients diagnosed with an IRD. After signing informed consent, peripheral blood or saliva was collected from 64 patients diagnosed with an IRD. Genetic testing was performed on each patient in a Clinical Laboratory Improvement Amendments of 1988 (CLIA) certified laboratory. Mutations were verified with Sanger sequencing and segregation analysis when possible. Visual acuity was measured with a traditional Snellen chart and converted to a logarithm of minimal angle of resolution (logMAR). Fundus images of dilated eyes were acquired with the Optos® camera (Dunfermline, UK). Horizontal line scans were obtained with spectral-domain optical coherence tomography (SDOCT; Spectralis, Heidelberg, Germany). Genetic testing combined with segregation analysis resolved molecular and clinical diagnoses for 75% of patients. Ten novel mutations were found and unique genotype phenotype associations were made for the genes RP2 and CEP83. Collective knowledge is thereby expanded of the genetic basis and phenotypic correlation in IRD.
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Affiliation(s)
- Jacob Lynn
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Austin Raney
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Nathaniel Britton
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Josh Ramoin
- College of Osteopathic Medicine, Oklahoma State University, Stillwater, OK 74078, USA
| | - Ryan W. Yang
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Bojana Radojevic
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Cynthia K. McClard
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Ronald Kingsley
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Razek Georges Coussa
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
| | - Lea D. Bennett
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Dean McGee Eye Institute, Oklahoma City, OK 73104, USA
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10
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McClard CK, Pollalis D, Jamshidi F, Kingsley R, Lee SY. Utility of No-Charge Panel Genetic Testing for Inherited Retinal Diseases in a Real-World Clinical Setting. JOURNAL OF VITREORETINAL DISEASES 2022; 6:351-357. [PMID: 36213299 PMCID: PMC9542391 DOI: 10.1177/24741264221100936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
PURPOSE To show the utility of genetic testing in inherited retinal disease (IRD) patients. METHODS This retrospective cohort study was performed at a single academic center and comprised 59 patients clinically diagnosed with IRD who had testing via the Invitae IRD Panel (Invitae Corp). Samples were collected from August 2019 to April 2021. The rates of genetic diagnosis and disease-category specific results (ie, positive, undetermined, negative) were assessed. RESULTS Testing results were returned a mean of 20 days (range, 14-28 days) after submission. Of the samples, 50.8% (30/59) had a diagnostic yield. By disease category, the yield was 46.4% (13/28) nonsyndromic retinitis pigmentosa (RP), 50.0% (4/8) syndromic RP, 46.2% (6/13) macular dystrophies, 75.0% (3/4) cone or cone-rod dystrophies, and 80.0% (4/5) other retinopathies; there were no cases of rod dystrophies. The results were undetermined in 47.5% of patients (28/59) because of identification of only 1 recessive mutation (5.1%; 3/59), 1 recessive mutation and at least 1 variant of uncertain significance (VUS) (13.6%; 8/59), or VUS only (28.8%; 17/59). One patient (1.7%) received negative testing results with no mutations or VUS identified. CONCLUSIONS Open-access, no-charge panel testing offers a reasonable diagnostic yield. Accurate clinical diagnosis of IRD before testing and acknowledgment of the limitations of panel testing are critical. The results add to the current estimates of the value of genetic testing for retina specialists in the management of IRD.
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Affiliation(s)
- Cynthia K. McClard
- Ophthalmology, Dean McGee Eye
Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK,
USA
| | - Dimitrios Pollalis
- Ophthalmology, Dean McGee Eye
Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK,
USA
- USC Roski Eye Institute, USC Ginsburg
Institute for Biomedical Therapeutics and Department of Ophthalmology, Keck School
of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Farzad Jamshidi
- Ophthalmology, Dean McGee Eye
Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK,
USA
| | - Ronald Kingsley
- Ophthalmology, Dean McGee Eye
Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK,
USA
| | - Sun Young Lee
- Ophthalmology, Dean McGee Eye
Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK,
USA
- USC Roski Eye Institute, USC Ginsburg
Institute for Biomedical Therapeutics and Department of Ophthalmology, Keck School
of Medicine, University of Southern California, Los Angeles, CA, USA
- Department of Physiology, University of
Oklahoma Health Sciences Center, Oklahoma City, OK, USA
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11
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Iosifidis C, Liu J, Gale T, Ellingford JM, Campbell C, Ingram S, Chandler K, Parry NRA, Black GC, Sergouniotis PI. Clinical and genetic findings in TRPM1-related congenital stationary night blindness. Acta Ophthalmol 2022; 100:e1332-e1339. [PMID: 35633130 DOI: 10.1111/aos.15186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 05/05/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE Congenital stationary night blindness (CSNB) is a heterogeneous group of Mendelian retinal disorders that present in childhood. Biallelic variants altering the protein-coding region of the TRPM1 gene are one of the commonest causes of CSNB. Here, we report the clinical and genetic findings in 10 unrelated individuals with TRPM1-retinopathy. METHODS Study subjects were recruited through a tertiary clinical ophthalmic genetic service at Manchester, UK. All participants underwent visual electrodiagnostic testing and panel-based genetic analysis. RESULTS Study subjects had a median age of 8 years (range: 3-20 years). All probands were myopic and had electroretinographic findings in keeping with complete CSNB. Notably, three probands reported no night vision problems. Fourteen different disease-associated TRPM1 variants were detected. One individual was homozygous for the NM_001252024.2 (TRPM1):c.965 + 29G>A variant and a mini-gene assay highlighted that this change results in mis-splicing and premature protein termination. Additionally, two unrelated probands who had CSNB and mild neurodevelopmental abnormalities were found to carry a 15q13.3 microdeletion. This copy number variant encompasses seven genes, including TRPM1, and was encountered in the heterozygous state and in trans with a missense TRPM1 variant in each case. CONCLUSION Our findings highlight the importance of comprehensive genomic analysis, beyond the exons and protein-coding regions of genes, for individuals with CSNB. When this characteristic retinal phenotype is accompanied by extraocular findings (including learning and/or behavioural difficulties), a 15q13.3 microdeletion should be suspected. Focused analysis (e.g. microarray testing) is recommended to look for large-scale deletions encompassing TRPM1 in patients with CSNB and neurodevelopmental abnormalities.
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Affiliation(s)
- Christos Iosifidis
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
- Manchester Royal Eye Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Jingshu Liu
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
| | - Theodora Gale
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Jamie M. Ellingford
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Christopher Campbell
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Stuart Ingram
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Kate Chandler
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Neil R. A. Parry
- Manchester Royal Eye Hospital Manchester University NHS Foundation Trust Manchester UK
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
| | - Graeme C. Black
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
| | - Panagiotis I. Sergouniotis
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicines and Health University of Manchester Manchester UK
- Manchester Centre for Genomic Medicine, Saint Mary's Hospital Manchester University NHS Foundation Trust Manchester UK
- Manchester Royal Eye Hospital Manchester University NHS Foundation Trust Manchester UK
- Institute of Biochemistry and Molecular Genetics, Faculty of Medicine University of Ljubljana Ljubljana Slovenia
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12
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Wang J, Wang Y, Jiang Y, Li X, Xiao X, Li S, Jia X, Sun W, Wang P, Zhang Q. Autosomal Dominant Retinitis Pigmentosa-Associated TOPORS Protein Truncating Variants Are Exclusively Located in the Region of Amino Acid Residues 807 to 867. Invest Ophthalmol Vis Sci 2022; 63:19. [PMID: 35579903 PMCID: PMC9123486 DOI: 10.1167/iovs.63.5.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Heterozygous truncating variants of TOPORS have been reported to cause autosomal dominant retinitis pigmentosa (adRP). The purpose of this study was to investigate whether all heterozygous truncating variants, including copy number variants (CNVs), are pathogenic. Methods TOPORS truncating variants were collected and reviewed through an in-house dataset and existing databases. Individuals with truncating variants underwent ophthalmological evaluation. Results Six truncating variants were detected in seven families. Three N-terminus truncating variants were detected in three families without RP, and the other three were identified in four unrelated families with typical RP. Based on the in-house dataset and published literature, 17 truncating variants were identified in 47 families with RP. All RP-associated truncating alleles, except one, were distributed in the last exon of TOPORS and clustered in amino acid residues 807 to 867 (46/47, 97.9%). Conversely, in the gnomAD database, only one truncating allele (1/27, 3.7%) was in this region, and the others were outside (26/27, 96.3%), suggesting that the pathogenic truncating variants were significantly clustered in residues 807 to 867 (χ2 = 65.6, P = 1.1 × 10–17). Additionally, three CNVs involving the N-terminus of TOPORS were recorded in control populations but were absent in affected patients. Conclusions This study suggests that all pathogenic truncating variants of TOPORS were clustered in residues 807 to 867, whereas the truncating variants outside this region and the CNVs involving the N-terminus were not associated with RP. A dominant-negative effect, rather than haploinsufficiency, is speculated to be the underlying pathogenesis. These findings provide valuable information for interpreting variation in TOPORS and other genes in similar situations, especially for CNVs.
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Affiliation(s)
- Junwen Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yingwei Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yi Jiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xueqing Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiaoyun Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Panfeng Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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13
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He K, Zhou Y, Li N. Mutations of TOPORS identified in families with retinitis pigmentosa. Ophthalmic Genet 2022; 43:371-377. [PMID: 35254173 DOI: 10.1080/13816810.2022.2039721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Kaiwen He
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
| | - Yunyu Zhou
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
| | - Ningdong Li
- Department of Ophthalmology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, China 100045
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14
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Lam BL, Leroy BP, Black G, Ong T, Yoon D, Trzupek K. Genetic testing and diagnosis of inherited retinal diseases. Orphanet J Rare Dis 2021; 16:514. [PMID: 34906171 PMCID: PMC8670140 DOI: 10.1186/s13023-021-02145-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 11/28/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal diseases (IRDs) are a diverse group of degenerative diseases of the retina that can lead to significant reduction in vision and blindness. Because of the considerable phenotypic overlap among IRDs, genetic testing is a critical step in obtaining a definitive diagnosis for affected individuals and enabling access to emerging gene therapy–based treatments and ongoing clinical studies. While advances in molecular diagnostic technologies have significantly improved the understanding of IRDs and identification of disease-causing variants, training in genetic diagnostics among ophthalmologists is limited. In this review, we will provide ophthalmologists with an overview of genetic testing for IRDs, including the types of available testing, variant interpretation, and genetic counseling. Additionally, we will discuss the clinical applications of genetic testing in the molecular diagnosis of IRDs through case studies.
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Affiliation(s)
- Byron L Lam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, 900 NW 17th Street, Miami, FL, 33156, USA.
| | - Bart P Leroy
- Department of Ophthalmology, Ghent University and Ghent University Hospital, Ghent, Belgium.,Ophthalmic Genetics and Visual Electrophysiology, Division of Ophthalmology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Graeme Black
- UK Inherited Retinal Disease Consortium, Manchester, UK.,Genomics England Clinical Interpretation Partnership, Manchester, UK.,Manchester Centre for Genomic Medicine, St. Mary's Hospital, Manchester, UK
| | - Tuyen Ong
- Ring Therapeutics, Cambridge, MA, USA
| | | | - Karmen Trzupek
- Ocular and Rare Disease Genetics Services, InformedDNA, St Petersburg, FL, USA
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15
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Azhar Baig HM, Ansar M, Iqbal A, Naeem MA, Quinodoz M, Calzetti G, Iqbal M, Rivolta C. Genetic analysis of consanguineous Pakistani families with congenital stationary night blindness. Ophthalmic Res 2021; 65:104-110. [PMID: 34781300 DOI: 10.1159/000520895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 10/28/2021] [Indexed: 11/19/2022]
Abstract
AIM Congenital stationary night blindness (CSNB) is a rare, largely non progressive, inherited retinal disorder that can be clinically classified on the basis of fundus and electroretinogram (ERG) abnormalities. METHODS We analyzed four large consanguineous families from the Southern Punjab region of Pakistan including multiple individuals affected with CSNB. Exome sequencing (ES) was performed in probands of all four families; Sanger sequencing was performed in additional members to test co-segregation of the variants identified. RESULTS We identified two novel and likely pathogenic variants in two pedigrees, namely NM_002905.4:c.668A>C (p.Gln223Pro) in RDH5, and NM_022567.2:c.908del (p.Gly303ValfsTer45) in NYX. In the two other families, the variants NM_002905.4:c.319G>C (p.Gly107Arg) in RDH5 and NM_000541.5:c.874C>T (p.Arg292Ter) in SAG were identified. These variants have been reported previously, but not in the Pakistani population. CONCLUSIONS Our findings expand the mutational spectrum of CSNB, in particular within the population of Southern Punjab.
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Affiliation(s)
- Hafiz Muhammad Azhar Baig
- Department of Biotechnology, Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Muhammad Ansar
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Afia Iqbal
- Department of Zoology, Lahore College for Women University, Lahore, Pakistan
| | - Muhammad Asif Naeem
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Mathieu Quinodoz
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Giacomo Calzetti
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Muhammad Iqbal
- Department of Biotechnology, Institute of Biochemistry, Biotechnology and Bioinformatics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
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16
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Yang J, Zhou L, Ouyang J, Xiao X, Sun W, Li S, Zhang Q. Genotype-Phenotype Analysis of RPGR Variations: Reporting of 62 Chinese Families and a Literature Review. Front Genet 2021; 12:600210. [PMID: 34745198 PMCID: PMC8565807 DOI: 10.3389/fgene.2021.600210] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 04/27/2021] [Indexed: 02/05/2023] Open
Abstract
Purpose RPGR is the most common cause of X-linked retinitis pigmentosa (RP), of which female carriers are also frequently affected. The aim of the current study was to explore the RPGR variation spectrum and associated phenotype based on the data from our lab and previous studies. Methods Variants in RPGR were selected from exome sequencing data of 7,092 probands with different eye conditions. The probands and their available family members underwent comprehensive ocular examinations. Similar data were collected from previous reports through searches in PubMed, Web of Science, and Google Scholar. Systematic analyses of genotypes, phenotypes and their correlations were performed. Results A total of 46 likely pathogenic variants, including nine missense and one in-frame variants in RCC1-like domain and 36 truncation variants, in RPGR were detected in 62 unrelated families in our in-house cohort. In addition, a total of 585 variants, including 491 (83.9%) truncation variants, were identified from the literature. Systematic analysis of variants from our in-house dataset, literature, and gnomAD suggested that most of the pathogenic variants of RPGR were truncation variants while pathogenic missense and in-frame variants were enriched in the RCC1-like domain. Phenotypic variations were present between males and female carriers, including more severe refractive error but better best corrected visual acuity (BCVA) in female carriers than those in males. The male patients showed a significant reduction of BCVA with increase of age and males with exon1-14 variants presented a better BCVA than those with ORF15 variants. For female carriers, the BCVA also showed significant reduction with increase of age, but BCVA in females with exon1-14 variants was not significant difference compared with those with ORF15 variants. Conclusion Most pathogenic variants of RPGR are truncations. Missense and in-frame variants located outside of the RCC1-like domain might be benign and the pathogenicity criteria for these variants should be considered with greater caution. The BCVA and refractive error are different between males and female carriers. Increase of age and location of variants in ORF15 contribute to the reduction of BCVA in males. These results are valuable for understanding genotypes and phenotypes of RPGR.
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Affiliation(s)
- Junxing Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lin Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.,Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Jiamin Ouyang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xueshan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shiqiang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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Ratnapriya R, Jacobson SG, Cideciyan AV, English MA, Roman AJ, Sumaroka A, Sheplock R, Swaroop A. A Novel ARL3 Gene Mutation Associated With Autosomal Dominant Retinal Degeneration. Front Cell Dev Biol 2021; 9:720782. [PMID: 34485303 PMCID: PMC8416110 DOI: 10.3389/fcell.2021.720782] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 07/07/2021] [Indexed: 12/18/2022] Open
Abstract
Despite major progress in the discovery of causative genes, many individuals and families with inherited retinal degenerations (IRDs) remain without a molecular diagnosis. We applied whole exome sequencing to identify the genetic cause in a family with an autosomal dominant IRD. Eye examinations were performed and affected patients were studied with electroretinography and kinetic and chromatic static perimetry. Sequence variants were analyzed in genes (n = 271) associated with IRDs listed on the RetNet database. We applied a stepwise filtering process involving the allele frequency in the control population, in silico prediction tools for pathogenicity, and evolutionary conservation to prioritize the potential causal variant(s). Sanger sequencing and segregation analysis were performed on the proband and other family members. The IRD in this family is expressed as a widespread progressive retinal degeneration with maculopathy. A novel heterozygous variant (c.200A > T) was identified in the ARL3 gene, leading to the substitution of aspartic acid to valine at position 67. The Asp67 residue is evolutionary conserved, and the change p.Asp67Val is predicted to be pathogenic. This variant was segregated in affected members of the family and was absent from an unaffected individual. Two previous reports of a de novo missense mutation in the ARL3 gene, each describing a family with two affected generations, are the only examples to date of autosomal dominant IRD associated with this photoreceptor gene. Our results, identifying a novel pathogenic variant in ARL3 in a four-generation family with a dominant IRD, augment the evidence that the ARL3 gene is another cause of non-syndromic retinal degeneration.
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Affiliation(s)
- Rinki Ratnapriya
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, United States.,Department of Ophthalmology, Baylor College of Medicine, Houston, TX, United States
| | - Samuel G Jacobson
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Artur V Cideciyan
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Milton A English
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Alejandro J Roman
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Alexander Sumaroka
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Rebecca Sheplock
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, United States
| | - Anand Swaroop
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
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18
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Colombo L, Maltese PE, Castori M, El Shamieh S, Zeitz C, Audo I, Zulian A, Marinelli C, Benedetti S, Costantini A, Bressan S, Percio M, Ferri P, Abeshi A, Bertelli M, Rossetti L. Molecular Epidemiology in 591 Italian Probands With Nonsyndromic Retinitis Pigmentosa and Usher Syndrome. Invest Ophthalmol Vis Sci 2021; 62:13. [PMID: 33576794 PMCID: PMC7884295 DOI: 10.1167/iovs.62.2.13] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Purpose To describe the molecular epidemiology of nonsyndromic retinitis pigmentosa (RP) and Usher syndrome (US) in Italian patients. Methods A total of 591 probands (315 with family history and 276 sporadics) were analyzed. For 155 of them, we performed a family segregation study, considering a total of 382 relatives. Probands were analyzed by a customized multigene panel approach. Sanger sequencing was used to validate all genetic variants and to perform family segregation studies. Copy number variants of selected genes were analyzed by multiplex ligation-dependent probe amplification. Four patients who tested negative to targeted next-generation sequencing analysis underwent clinical exome sequencing. Results The mean diagnostic yield of molecular testing among patients with a family history of retinal disorders was 55.2% while the diagnostic yield including sporadic cases was 37.4%. We found 468 potentially pathogenic variants, 147 of which were unpublished, in 308 probands and 66 relatives. Mean ages of onset of the different classes of RP were autosomal dominant RP, 19.3 ± 12.6 years; autosomal recessive RP, 23.2 ± 16.6 years; X-linked RP, 13.9 ± 9.9 years; and Usher syndrome, 18.9 ± 9.5 years. We reported potential new genotype-phenotype correlations in three probands, two revealed by TruSight One testing. All three probands showed isolated RP caused by biallelic variants in genes usually associated with syndromes such as PERCHING and Senior-Loken or with retinal dystrophy, iris coloboma, and comedogenic acne syndrome. Conclusions This is the largest molecular study of Italian patients with RP in the literature, thus reflecting the epidemiology of the disease in Italy with reasonable accuracy.
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Affiliation(s)
- Leonardo Colombo
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, Milan, Italy
| | | | - Marco Castori
- Division of Medical Genetics, Fondazione IRCCS-Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Said El Shamieh
- Department of Medical Laboratory Technology, Faculty of Health Sciences, Beirut Arab University, Beirut, Lebanon.,Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHUSight Restore, INSERM-DGOS CIC1423, Paris, France
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHUSight Restore, INSERM-DGOS CIC1423, Paris, France
| | | | | | | | | | | | | | - Paolo Ferri
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, Milan, Italy
| | - Andi Abeshi
- MAGI's Lab s.r.l., Rovereto, Italy.,Department of Otolaryngology, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy
| | | | - Luca Rossetti
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, Milan, Italy
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Mermeklieva E, Kamenarova K, Mihova K, Shakola F, Kaneva R. A rare case of RGR/CDHR1 haplotype identified in Bulgarian patient with cone-rod dystrophy. Ophthalmic Genet 2021; 42:747-752. [PMID: 34229535 DOI: 10.1080/13816810.2021.1946700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
AIM To present a rare clinical case of CDHR1-related retinopathy with cone and rod involvementconfirmed clinically, electrophysiologically and genetically as a cone-rod dystrophy. MATERIAL AND METHODS A 26-year-old woman underwent detailed ophthalmic examinationincluding fundus photography, full-field and multifocal electroretinography, visual field testing, optical coherence tomography and fluorescein angiography, which established the clinical diagnosis. Next-generation sequencing of a custom panel including 140 of the most common genes for inherited retinal degenerations was used for mutation screening. RESULTS The symptoms onset was two years ago included gradual loss of vision and photophobia. The clinical findings were reduced visual acuity, central and peripheral scotomas, sporadic pigmentary cells localized mainly in the peripheral retina, a thinner retina in the macula and peripherally, moderate retinal vessels attenuation and reduced cone and rod ERG responses. The genetic analysisfound that the patient was homozygous for two already reported mutations: RGR-c.196A>C (p.Ser66Arg) variant and a co-segregating frame-shift deletion in CDHR1-c.2522_2528delTCTCTGA (p.Ile841Serfs119*). Segregation analysis showed that the two mutations were transmitted by the asymptomatic heterozygous parents. CONCLUSION The rare haplotype of RGR mutation co-segregating incis- with CDHR1 mutation in our patient has been previously described in Albanian patients with recessive retinal dystrophy. Our findings add further support to the hypothesis of a common ancestral haplotype spread in the Balkan population. The comprehensive clinical, electrophysiological and genetic testing of patients with rare hereditary retinal dystrophies is essential for the correct diagnosis and the choice of potential novel therapies.
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Affiliation(s)
- Elena Mermeklieva
- Clinic of Оphthalmology, "Lozenetz" University Hospital, Medical Faculty, Sofia University "St. Kliment Ohridski", Sofia, Bulgaria
| | - Kunka Kamenarova
- Molecular Medicine Center, Department of Medical Chemistry and Biochemistry, Medical Faculty, Medical University - Sofia, Sofia, Bulgaria
| | - Kalina Mihova
- Molecular Medicine Center, Department of Medical Chemistry and Biochemistry, Medical Faculty, Medical University - Sofia, Sofia, Bulgaria
| | - Felitsiya Shakola
- Molecular Medicine Center, Department of Medical Chemistry and Biochemistry, Medical Faculty, Medical University - Sofia, Sofia, Bulgaria
| | - Radka Kaneva
- Molecular Medicine Center, Department of Medical Chemistry and Biochemistry, Medical Faculty, Medical University - Sofia, Sofia, Bulgaria
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20
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Next-Generation Sequencing Applications for Inherited Retinal Diseases. Int J Mol Sci 2021; 22:ijms22115684. [PMID: 34073611 PMCID: PMC8198572 DOI: 10.3390/ijms22115684] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 05/21/2021] [Accepted: 05/22/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal diseases (IRDs) represent a collection of phenotypically and genetically diverse conditions. IRDs phenotype(s) can be isolated to the eye or can involve multiple tissues. These conditions are associated with diverse forms of inheritance, and variants within the same gene often can be associated with multiple distinct phenotypes. Such aspects of the IRDs highlight the difficulty met when establishing a genetic diagnosis in patients. Here we provide an overview of cutting-edge next-generation sequencing techniques and strategies currently in use to maximise the effectivity of IRD gene screening. These techniques have helped researchers globally to find elusive causes of IRDs, including copy number variants, structural variants, new IRD genes and deep intronic variants, among others. Resolving a genetic diagnosis with thorough testing enables a more accurate diagnosis and more informed prognosis and should also provide information on inheritance patterns which may be of particular interest to patients of a child-bearing age. Given that IRDs are heritable conditions, genetic counselling may be offered to help inform family planning, carrier testing and prenatal screening. Additionally, a verified genetic diagnosis may enable access to appropriate clinical trials or approved medications that may be available for the condition.
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21
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Establishing Genotype-phenotype Correlation in USH2A-related Disorders to Personalize Audiological Surveillance and Rehabilitation. Otol Neurotol 2021; 41:431-437. [PMID: 32176120 DOI: 10.1097/mao.0000000000002588] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE USH2A-related disorders are characterised by genetic and phenotypic heterogeneity, and are associated with a spectrum of sensory deficits, ranging from deaf blindness to blindness with normal hearing. It has been previously proposed that the presence of specific USH2A alleles can be predictive of unaffected hearing. This study reports the clinical and genetic findings in a group of patients with USH2A-related disease and evaluates the validity of the allelic hierarchy model. PATIENTS AND INTERVENTION USH2A variants from 27 adults with syndromic and nonsyndromic USH2A-related disease were analyzed according to a previously reported model of allelic hierarchy. The analysis was replicated on genotype-phenotype correlation information from 197 individuals previously reported in 2 external datasets. MAIN OUTCOME MEASURE Genotype-phenotype correlations in USH2A-related disease. RESULTS A valid allelic hierarchy model was observed in 93% of individuals with nonsyndromic USH2A-retinopathy (n = 14/15) and in 100% of patients with classic Usher syndrome type IIa (n = 8/8). Furthermore, when two large external cohorts of cases were combined, the allelic hierarchy model was valid across 85.7% (n = 78/91) of individuals with nonsyndromic USH2A-retinopathy and 95% (n = 123/129) of individuals with classic Usher syndrome type II (p = 0.012, χ test). Notably, analysis of all three patient datasets revealed that USH2A protein truncating variants were reported most frequently in individuals with hearing loss. CONCLUSION Genetic testing results in individuals suspected to have an USH2A-related disorder have the potential to facilitate personalized audiological surveillance and rehabilitation pathways.
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22
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Cehajic-Kapetanovic J, McClements ME, Whitfield J, Shanks M, Clouston P, MacLaren RE. Association of a Novel Intronic Variant in RPGR With Hypomorphic Phenotype of X-Linked Retinitis Pigmentosa. JAMA Ophthalmol 2020; 138:1151-1158. [PMID: 32970112 PMCID: PMC7516822 DOI: 10.1001/jamaophthalmol.2020.3634] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Importance Pathogenic variants in retinitis pigmentosa GTPase regulator (RPGR) gene typically lead to a severe form of X-linked retinitis pigmentosa, which is associated with early severe vision loss. Objective To investigate an X-linked retinal degeneration family with atypical preservation of visual acuity in the presence of a novel deep intronic splice site RPGR c.779-5T>G variant. Design, Setting, and Participants In this case series, 3 members of an X-linked retinal degeneration family were studied by in-depth phenotyping and genetic screening at a single center. Data were collected and analyzed from November 2018 to March 2020. Main Outcomes and Measures Data were collected on full ophthalmic history, examination, and retinal imaging. A full retinitis pigmentosa gene panel was analyzed by next-generation sequencing. The pathogenicity of the RPGR c.779-5T>G variant was assessed by in silico splice prediction tools and by purpose-designed in vitro splicing assay. Results An 84-year-old man was referred with clinical diagnosis of choroideremia and possible inclusion into a gene therapy trial. He presented with late-stage retinal degeneration and unusually preserved visual acuity (78 and 68 ETRDS letters) that clinically resembled choroideremia. His 23-year-old grandson was still in early stages of degeneration but showed a very different clinical picture, typical of retinitis pigmentosa. Next-generation sequencing identified a sole RPGR c.779-5T>G variant of undetermined pathogenicity in both cases. The daughter of the proband showed an RPGR carrier phenotype and was confirmed to carry the same variant. The molecular analysis confirmed that the RPGR c.779-5T>G variation reduced the efficiency of intron splicing compared with wild type, leading to a population of mutant and normal transcripts. The predicted consequences of the pathogenic variant are potential use of an alternative splice acceptor site or complete skipping of exon 8, resulting in truncated forms of the RPGR protein with different levels of glutamylation. Conclusions and Relevance These results support the importance of careful interpretation of inconsistent clinical phenotypes between family members. Using a molecular splicing assay, a new pathogenic variant in a noncoding region of RPGR was associated with a proportion of normal and hypomorphic RPGR, where cones are likely to survive longer than expected, potentially accounting for the preserved visual acuity observed in this family.
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Affiliation(s)
- Jasmina Cehajic-Kapetanovic
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, England
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
| | - Michelle E. McClements
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, England
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
| | - Jennifer Whitfield
- Genetics Laboratories, Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
| | - Morag Shanks
- Genetics Laboratories, Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
| | - Penny Clouston
- Genetics Laboratories, Churchill Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
| | - Robert E. MacLaren
- Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, England
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, England
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23
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Hull S, Kiray G, Chiang JPW, Vincent AL. Molecular and phenotypic investigation of a New Zealand cohort of childhood-onset retinal dystrophy. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:708-717. [PMID: 32856788 DOI: 10.1002/ajmg.c.31836] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022]
Abstract
Inherited retinal diseases are clinically heterogeneous and are associated with nearly 300 different genes. In this retrospective, observational study of a consecutive cohort of 159 patients (134 families) with childhood-onset (<16 years of age) retinal dystrophy, molecular investigations, and in-depth phenotyping were performed to determine key clinical and molecular characteristics. The most common ocular phenotype was rod-cone dystrophy in 40 patients. Leber Congenital Amaurosis, the most severe form of retinal dystrophy, was present in 10 patients, and early onset severe retinal dystrophy in 22 patients. Analysis has so far identified 131 pathogenic or likely pathogenic variants including 22 novel variants. Molecular diagnosis was achieved in 112 of 134 families (83.6%) by NGS gene panel investigation in 60 families, Sanger sequencing in 27 families, and Asper microarray in 25 families. An additional nine variants of uncertain significance were also found including three novel variants. Variants in 36 genes have been identified with the most common being ABCA4 retinopathy in 36 families. Five sporadic retinal dystrophy patients were found to have variants in dominant and X-linked genes (CRX, RHO, RP2, and RPGR) resulting in more accurate genetic counseling of inheritance for these families. Variants in syndromic associated genes including ALMS1, SDCCAG8, and PPT1 were identified in eight families enabling directed systemic care.
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Affiliation(s)
- Sarah Hull
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, Greenlane Clinical Centre, Auckland District Health Board, Auckland, New Zealand.,Institute of Ophthalmology, University College London, London, UK
| | - Gulunay Kiray
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, Greenlane Clinical Centre, Auckland District Health Board, Auckland, New Zealand
| | | | - Andrea L Vincent
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, Greenlane Clinical Centre, Auckland District Health Board, Auckland, New Zealand
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24
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Weisschuh N, Obermaier CD, Battke F, Bernd A, Kuehlewein L, Nasser F, Zobor D, Zrenner E, Weber E, Wissinger B, Biskup S, Stingl K, Kohl S. Genetic architecture of inherited retinal degeneration in Germany: A large cohort study from a single diagnostic center over a 9-year period. Hum Mutat 2020; 41:1514-1527. [PMID: 32531858 DOI: 10.1002/humu.24064] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/27/2020] [Accepted: 05/04/2020] [Indexed: 12/29/2022]
Abstract
We aimed to unravel the molecular genetic basis of inherited retinal degeneration (IRD) in a comprehensive cohort of patients diagnosed in the largest center for IRD in Germany. A cohort of 2,158 affected patients from 1,785 families diagnosed with IRD was analyzed by targeted next-generation sequencing (NGS). Patients with single-gene disorders (i.e., choroideremia and retinoschisis) were analyzed by Sanger sequencing and multiplex ligation-dependent probe amplification. Our study cohort accounts for ∼7% of the estimated 30,000 patients with IRD in Germany, thereby providing representative data for both the prevalence of IRDs and the mutation spectrum of IRD genes for the population in Germany. We achieved a molecular diagnostic rate of 35-95%, depending on the clinical entities, with a high detection rate for achromatopsia, retinoschisis, and choroideremia, and a low detection rate for central areolar choroidal dystrophy and macular dystrophy. A total of 1,161 distinct variants were identified, including 501 novel variants, reaffirming the known vast genetic heterogeneity of IRD in a mainly outbred European population. This study demonstrates the clinical utility of panel-based NGS in a large and highly heterogeneous cohort from an outbred population and for the first time gives a comprehensive representation of the genetic landscape of IRDs in Germany. The data are valuable and crucial for the scientific community and healthcare providers, but also for the pharmaceutical industry in the progressing field of personalized medicine and gene therapy.
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Affiliation(s)
- Nicole Weisschuh
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Carolin D Obermaier
- Praxis für Humangenetik, Tübingen, Germany.,Center for Genomics and Transcriptomics, CeGaT GmbH, Tübingen, Germany
| | - Florian Battke
- Center for Genomics and Transcriptomics, CeGaT GmbH, Tübingen, Germany
| | - Antje Bernd
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Laura Kuehlewein
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Fadi Nasser
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Ditta Zobor
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Eberhart Zrenner
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
| | - Eva Weber
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Bernd Wissinger
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Saskia Biskup
- Praxis für Humangenetik, Tübingen, Germany.,Center for Genomics and Transcriptomics, CeGaT GmbH, Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Center for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
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25
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Shah M, Shanks M, Packham E, Williams J, Haysmoore J, MacLaren RE, Németh AH, Clouston P, Downes SM. Next generation sequencing using phenotype-based panels for genetic testing in inherited retinal diseases. Ophthalmic Genet 2020; 41:331-337. [PMID: 32543920 DOI: 10.1080/13816810.2020.1778736] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Diagnostic next generation sequencing (NGS) services for patients with inherited retinal diseases (IRD) traditionally use gene panel based approaches, which have cost and resource implications. Phenotype-based gene panels use a targeted strategy with further testing protocols, if initial results are negative. We present the molecular findings of the Oxford phenotype-based NGS panels for genetic testing in IRD. METHODS Results of 655 consecutive patients referred for phenotype-based panel testing over 54 months were analysed to assess diagnostic yield. RESULTS Variants were identified in 450 patients (68.7%). The overall diagnostic yield from phenotype-based panels was 42.8%. The diagnostic yield was highest from panels representing distinct clinical phenotypes: Usher panel 90.9% and congenital stationary night blindness panel 75.0%. Retinitis pigmentosa/rod-cone dystrophy was the commonest presenting phenotype (n = 243) and Usher syndrome was the commonest presenting syndromic disease (n = 39). Patients presenting with late-onset (≥50 years) macular disease had a lower diagnostic yield (18.0%) compared with patients <50 years (24.2%). Additionally, a diagnostic yield of 1.8% was attributable to copy number variants. CONCLUSIONS Phenotype-based genetic testing panels provide a targeted testing approach and reduce bioinformatics demand. The overall diagnostic yield achieved in this study reflects the wide range of phenotypes that were referred. This pragmatic approach provides a high yield for early-onset and clearly defined genetically determined disorders but clinical utility is not as clear for late-onset macular disorders. This phenotype-based panel approach is clinician-referrer orientated, and can be used as a front-end virtual panel, when whole genome sequencing is introduced into diagnostic services for IRD.
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Affiliation(s)
- Mital Shah
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust , Oxford, UK.,Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford , Oxford, UK
| | - Morag Shanks
- Oxford Medical Genetics Laboratories, Churchill Hospital , Oxford, UK
| | - Emily Packham
- Oxford Medical Genetics Laboratories, Churchill Hospital , Oxford, UK
| | - Jonathan Williams
- Oxford Medical Genetics Laboratories, Churchill Hospital , Oxford, UK
| | - Jesse Haysmoore
- Oxford Medical Genetics Laboratories, Churchill Hospital , Oxford, UK
| | - Robert E MacLaren
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust , Oxford, UK.,Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford , Oxford, UK
| | - Andrea H Németh
- Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.,Nuffield Department of Clinical Neurosciences, University of Oxford , Oxford, UK
| | - Penny Clouston
- Oxford Medical Genetics Laboratories, Churchill Hospital , Oxford, UK
| | - Susan M Downes
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust , Oxford, UK.,Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford , Oxford, UK
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26
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Salmaninejad A, Motaee J, Farjami M, Alimardani M, Esmaeilie A, Pasdar A. Next-generation sequencing and its application in diagnosis of retinitis pigmentosa. Ophthalmic Genet 2020; 40:393-402. [PMID: 31755340 DOI: 10.1080/13816810.2019.1675178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Retinitis Pigmentosa (RP) is a major cause of heritable human blindness with a high genetic heterogeneity. It is characterized by the initial degeneration of rod photoreceptors followed by cone photoreceptors. RP is also a prominent reason of visual impairment, by a global prevalence of 1:4000. RP is usually specified with nyctalopia in puberty, followed by concentric visual field loss, that reflects the main impairment of rod photoreceptors; later in the life, as disease progresses, because of cone dysfunction, central vision loss also occurs. A precise molecular diagnosis is crucial for disease characterization and clinical prognosis. DNA sequencing is a powerful tool for deciphering various causes of different human diseases. The arrival of next-generation sequencing (NGS) technologies has diminished sequencing cost and considerably augmented the throughput, making whole-genome sequencing (WGS) a conceivable way for obtaining comprehensive genomic data and a more precise clinical decision. Nevertheless, the advantages gained from NGS technologies are among a number of challenges that must be sufficiently addressed before this technique can be altered from an investigation tools to a helpful method in routine clinical practices. This article aims to provide an overview about NGS technology and its related platforms. The challenges in the analysis and choosing an appropriate NGS method likewise their potential applications in clinical diagnosis are also discussed. The merit of such technique has been reflected in some recent studies where it is shown that using NGS and molecular information could help with clinical diagnosis, providing potential treatment options or changes, up-to-date family counseling and management.
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Affiliation(s)
- Arash Salmaninejad
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Jamshid Motaee
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahsa Farjami
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Maliheh Alimardani
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Alireza Pasdar
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Bioinformatics Research Group, Mashhad University of Medical Sciences, Mashhad, Iran.,Division of Applied Medicine,Medical School, University of Aberdeen, Foresterhill, Aberdeen, UK
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27
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Holtan JP, Selmer KK, Heimdal KR, Bragadóttir R. Inherited retinal disease in Norway - a characterization of current clinical and genetic knowledge. Acta Ophthalmol 2020; 98:286-295. [PMID: 31429209 DOI: 10.1111/aos.14218] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 07/23/2019] [Indexed: 02/06/2023]
Abstract
PURPOSE The purpose of this study was to characterize current clinical and genetic knowledge of patients with inherited retinal disease in Norway and give an estimate of the prevalence. These data are necessary to identify patients eligible for new personalized medicines, to facilitate genetic counselling for their families and to plan clinical follow-up. METHODS A patient registry including clinical and genetic data was established. Clinical data were retrieved during 2003-2018. Genetic testing was performed in the period 2007-2018. RESULTS The material included 866 patients with 41 clinical diagnoses at the cut-off date. The most prevalent diseases were as follows: retinitis pigmentosa (54%), Stargardt macular dystrophy (6.5%) and Leber congenital amaurosis (5.2%). A genetic diagnosis was identified in 32% of patients. In total, 207 disease-causing variants in 56 genes were reported. The most commonly reported disease-causing genes were ABCA4, USH2A and BEST1. The estimated adjusted minimum prevalence of inherited retinal disease in the south-east region of Norway was 1: 3,856 (2.6/10 000). CONCLUSION This population-based study demonstrated an estimated prevalence for all inherited retinal diseases in south-east Norway and described the distribution of clinical diagnoses, onset of symptoms, inheritance patterns and genetic data and thereby expands our knowledge of inherited retinal disease in Norway. The newly established registry and biobank will support patient feasibility for future clinical trials, treatment selection and counselling of families.
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Affiliation(s)
- Josephine Prener Holtan
- Department of Ophthalmology Oslo University Hospital Oslo Norway
- University of Oslo Oslo Norway
| | - Kaja Kristine Selmer
- Department of Medical Genetics Oslo University Hospital Oslo Norway
- Department of Research and Development Oslo University Hospital Oslo Norway
| | | | - Ragnheiður Bragadóttir
- Department of Ophthalmology Oslo University Hospital Oslo Norway
- University of Oslo Oslo Norway
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Clinical utility of genetic testing in 201 preschool children with inherited eye disorders. Genet Med 2019; 22:745-751. [PMID: 31848469 PMCID: PMC7118019 DOI: 10.1038/s41436-019-0722-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 11/25/2019] [Indexed: 12/13/2022] Open
Abstract
Purpose A key property to consider in all genetic tests is clinical utility, the ability of the test to influence patient management and health outcomes. Here we assess the current clinical utility of genetic testing in diverse pediatric inherited eye disorders (IEDs). Methods Two hundred one unrelated children (0–5 years old) with IEDs were ascertained through the database of the North West Genomic Laboratory Hub, Manchester, UK. The cohort was collected over a 7-year period (2011–2018) and included 74 children with bilateral cataracts, 8 with bilateral ectopia lentis, 28 with bilateral anterior segment dysgenesis, 32 with albinism, and 59 with inherited retinal disorders. All participants underwent panel-based genetic testing. Results The diagnostic yield of genetic testing for the cohort was 64% (ranging from 39% to 91% depending on the condition). The test result led to altered management (including preventing additional investigations or resulting in the introduction of personalized surveillance measures) in 33% of probands (75% for ectopia lentis, 50% for cataracts, 33% for inherited retinal disorders, 7% for anterior segment dysgenesis, 3% for albinism). Conclusion Genetic testing helped identify an etiological diagnosis in the majority of preschool children with IEDs. This prevented additional unnecessary testing and provided the opportunity for anticipatory guidance in significant subsets of patients.
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Yohe S, Sivasankar M, Ghosh A, Ghosh A, Holle J, Murugan S, Gupta R, Schimmenti LA, Vedam R, Thyagarajan B. Prevalence of mutations in inherited retinal diseases: A comparison between the United States and India. Mol Genet Genomic Med 2019; 8:e1081. [PMID: 31816670 PMCID: PMC7005662 DOI: 10.1002/mgg3.1081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 10/14/2019] [Accepted: 10/30/2019] [Indexed: 11/26/2022] Open
Abstract
Background Studies evaluating next‐generation sequencing (NGS) for retinal disorders may not reflect clinical practice. We report results of retrospective analysis of patients referred for clinical testing at two institutions (US and India). Methods This retrospective study of 131 patients who underwent clinically validated targeted NGS or exome sequencing for a wide variety of clinical phenotypes categorized results into a definitive, indeterminate, or negative molecular diagnosis. Results A definitive molecular diagnosis (52%) was more common in the India cohort (62% vs. 39%, p = .009), while an indeterminate molecular diagnosis occurred only in the US cohort (12%). In the US cohort, a lower diagnostic rate in Hispanic, non‐Caucasians (23%) was seen compared to Caucasians (57%). The India cohort had a high rate of homozygous variants (61%) and different frequency of genes involved compared to the US cohort. Conclusion Despite inherent limitations in clinical testing, the diagnostic rate across the two cohorts (52%) was similar to the 50%–65% diagnostic rate in the literature. However, the diagnostic rate was lower in the US cohort and appears partly explained by racial background. The high rate of consanguinity in the Indian population is reflected in the high rate of homozygosity for pathogenic mutations and may have implications for population level screening and genetic counseling. Clinical laboratories may note diagnostic rates that differ from the literature, due to factors such as heterogeneity in racial background or consanguinity rates in the populations being tested. This information may be useful for post‐test counseling.
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Affiliation(s)
- Sophia Yohe
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | | | | | | | - Jennifer Holle
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | | | | | - Lisa A Schimmenti
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
| | | | - Bharat Thyagarajan
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN
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Khurram Butt D, Gurbaxani A, Kozak I. Ultra-wide-Field Fundus Autofluorescence for the Detection of Inherited Retinal Disease in Difficult-to-Examine Children. J Pediatr Ophthalmol Strabismus 2019; 56:383-387. [PMID: 31743407 DOI: 10.3928/01913913-20190925-03] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 08/30/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE To assess the sensitivity of ultra-wide-field fundus autofluorescence (UWF-FAF) in comparison to fundus photography and clinical examination in diagnosing inherited retinal diseases in difficult-to-examine children. METHODS In this single-center, non-invasive observational study, children with suspected inherited retinal disease were examined clinically and then underwent UWF imaging (color fundus imaging and fundus autofluorescence) using the Optos Tx-200 imaging system (Optos, Dunfermline, United Kingdom). Patient ages ranged from 1 to 13 years (mean: 5.6 years). RESULTS The study included 112 eyes of 59 patients. Image acquisition was successful even in small children. UWF-FAF was the most sensitive in detecting the disease (94.9%), followed by UWF-CF (67.7%) and clinical examination (49.1%). CONCLUSIONS UWF-FAF is superior to fundus photography and clinical examination in detecting pathology in children with suspected inherited retinal diseases. It is a feasible, non-invasive, and quick tool that provides important clinical information in treating these patients. [J Pediatr Ophthalmol Strabismus. 2019;56(6):383-387.].
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Identification of CRB1 mutations in two Chinese consanguineous families exhibiting autosomal recessive retinitis pigmentosa. Mol Med Rep 2019; 20:2922-2928. [PMID: 31322236 DOI: 10.3892/mmr.2019.10495] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 06/12/2019] [Indexed: 11/05/2022] Open
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McVeigh E, Jones H, Black G, Hall G. The psychosocial and service delivery impact of genomic testing for inherited retinal dystrophies. J Community Genet 2019; 10:425-434. [PMID: 30680631 PMCID: PMC6591333 DOI: 10.1007/s12687-019-00406-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 01/02/2019] [Indexed: 11/25/2022] Open
Abstract
Next-generation sequencing (NGS) provides diagnostic information for many rare conditions. The evolution of NGS for panel, exome, and genome testing is set to be the platform for transforming genomic diagnosis in the National Health Service (NHS). Inherited retinal dystrophies (IRDs) are a highly genetically heterogeneous disease group causing progressive visual impairment. IRDs are ideal for an NGS panel approach due to phenotypic overlap and were one of the first diagnostic panels to be developed in the NHS. While diagnostic yield for patients with IRD has improved significantly with NGS, a proportion of patients remain without a diagnosis. The clinical value of NGS testing is well understood; however, the patient experience of panel testing is not well documented. Semi-structured qualitative telephone interviews were conducted with 23 participants with IRD who had undergone NGS testing. Interviews were transcribed verbatim and analysed using interpretative phenomenological analysis. Participants' experiences were interpreted to explore the psychosocial and service delivery impact of this testing technology, inclusive of those who received a pathogenic, negative, carrier status or variant of uncertain significance result. Collectively, three core themes were identified: (1) the journey towards a genomic diagnosis, (2) the impact of NGS testing, (3) service delivery of NGS tests. Disclosure of results had no reported adverse implications. Participants appreciated an open discussion about the potential for an uncertain or unexpected result, prior to testing. They valued pre-test counselling discussions, expert opinions and on-going care from genomic services.
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Affiliation(s)
- Eleanor McVeigh
- Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham Women's Hospital, Birmingham, UK.
| | - Harriet Jones
- Clinical Genetics Service, Birmingham Women's and Children's NHS Foundation Trust, Birmingham Women's Hospital, Birmingham, UK.
- Genetics Health Service, Northern Hub, Auckland City Hospital, Aukland, New Zealand.
| | - Graeme Black
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, St Mary's Hospital, Manchester, UK
| | - Georgina Hall
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, St Mary's Hospital, Manchester, UK
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Hu YS, Song H, Li Y, Xiao ZY, Li T. Whole-exome sequencing identifies novel mutations in genes responsible for retinitis pigmentosa in 2 nonconsanguineous Chinese families. Int J Ophthalmol 2019; 12:915-923. [PMID: 31236346 DOI: 10.18240/ijo.2019.06.06] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 09/25/2018] [Indexed: 12/26/2022] Open
Abstract
AIM To detect the pathogenetic mutations responsible for nonsyndromic autosomal recessive retinitis pigmentosa (RP) in 2 nonconsanguineous Chinese families. METHODS The clinical data, including detailed medical history, best corrected visual acuity (BCVA), slit-lamp biomicroscope examination, fundus photography, optical coherence tomography, static perimetry, and full field electroretinogram, were collected from the members of 2 nonconsanguineous Chinese families preliminarily diagnosed with RP. Genomic DNA was extracted from the probands and other available family members; whole-exome sequencing was conducted with the DNA samples provided by the probands, and all mutations detected by whole-exome sequencing were verified using Sanger sequencing in the probands and the other available family members. The verified novel mutations were further sequenced in 192 ethnicity matched healthy controls. RESULTS The patients from the 2 families exhibited the typical symptoms of RP, including night blindness and progressive constriction of the visual field, and the fundus examinations showed attenuated retinal arterioles, peripheral bone spicule pigment deposits, and waxy optic discs. Whole-exome sequencing revealed a novel nonsense mutation in FAM161A (c.943A>T, p.Lys315*) and compound heterozygous mutations in RP1L1 (c.56C>A, p.Pro19His; c.5470C>T, p.Gln1824*). The nonsense c.5470C>T, p.Gln1824* mutation was novel. All mutations were verified by Sanger sequencing. The mutation p.Lys315* in FAM161A co-segregated with the phenotype, and all the nonsense mutations were absent from the ethnicity matched healthy controls and all available databases. CONCLUSION We identify 2 novel mutations in genes responsible for autosomal recessive RP, and the mutation in FAM161A is reported for the first time in a Chinese population. Our result not only enriches the knowledge of the mutation frequency and spectrum in the genes responsible for nonsyndromic RP but also provides a new target for future gene therapy.
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Affiliation(s)
- Yan-Shan Hu
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Hui Song
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Yin Li
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Zi-Yun Xiao
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
| | - Tuo Li
- Department of Ophthalmology, the Central Hospital of Enshi Autonomous Prefecture, Enshi Clinical College of Wuhan University, Enshi 445000, Hubei Province, China
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Assessing the Joint Value of Genomic-Based Diagnostic Tests and Gene Therapies. J Pers Med 2019; 9:jpm9020028. [PMID: 31117188 PMCID: PMC6616850 DOI: 10.3390/jpm9020028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/10/2019] [Accepted: 05/16/2019] [Indexed: 12/12/2022] Open
Abstract
Gene therapy is an emerging type of treatment that may aim to provide a cure to individuals with a genetic mutation known to be causative of a specific disease. A diagnosis of the causative mutation must precede treatment with a in vivo gene therapy. Both achieving a genomic-based diagnosis and treatment with a gene therapy may result in substantial expenditures for health care systems. Uncertainties around the health care costs, risks, and benefits derived from diagnosis and treatment with a subsequent gene therapy suggests a need for developing an evidence base, underpinned by opportunity cost, to inform if, and how, these health technologies should be introduced into health care systems funded by finite budgets. This article discusses why current methods to evaluate health technologies (decision-analytic model-based cost-effectiveness analysis from the perspective of a health care system over a lifetime time horizon) are appropriate to quantify the costs and consequences of using genomic-based diagnostic tests and gene therapies in combination, rather than as separate interventions, within clinical practice. Evaluating the economic impact of test-and-treatment strategies will ensure that the opportunity cost of these health technologies is quantified fully for decision-makers who are responsible for allocating limited resources in health care systems.
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Birtel J, Gliem M, Oishi A, Müller PL, Herrmann P, Holz FG, Mangold E, Knapp M, Bolz HJ, Charbel Issa P. Genetic testing in patients with retinitis pigmentosa: Features of unsolved cases. Clin Exp Ophthalmol 2019; 47:779-786. [PMID: 30977268 DOI: 10.1111/ceo.13516] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 03/18/2019] [Accepted: 04/02/2019] [Indexed: 01/15/2023]
Abstract
IMPORTANCE Uncommon characteristics in genetically unsolved retinitis pigmentosa (RP) patients may indicate an incorrect clinical diagnosis or as yet unknown genetic causes resulting in specific retinal phenotypes. The diagnostic yield of targeted next-generation sequencing may be increased by a reasonable preselection of RP-patients. BACKGROUND To systematically evaluate and compare features of genetically solved and unsolved RP-patients. DESIGN Retrospective, observational study. PARTICIPANTS One-hundred and twelve consecutive RP-patients who underwent extensive molecular genetic analysis. METHODS Characterization of patients based on multimodal imaging and medical history. MAIN OUTCOME MEASURES Differences between genetically solved and unsolved RP-patients. RESULTS Compared to genetically solved patients (n = 77), genetically unsolved patients (n = 35) more frequently had an age of disease-onset above 30 years (60% vs 8%; P < 0.0001), showed atypical fundus features (49% vs 8%; P < 0. 0001) and indicators for phenocopies (eg, autoimmune diseases) (17% vs 0%; P < 0. 001). Evidence for a particular inheritance pattern was less common (20% vs 49%; P < 0. 01). The diagnostic yield was 84% (71/85) in patients with first symptoms below 30 years-of-age, compared to 69% (77/112) in the overall cohort. The other selection criteria alone or in combination resulted in limited further increase of the diagnostic yield (up to 89%) while excluding considerably more patients (up to 56%) from genetic testing. CONCLUSIONS AND RELEVANCE The medical history and retinal phenotype differ between genetically solved and a subgroup of unsolved RP-patients, which may reflect undetected genotypes or retinal conditions mimicking RP. Patient stratification may inform on the individual likelihood of identifying disease-causing mutations and may impact patient counselling.
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Affiliation(s)
- Johannes Birtel
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | - Martin Gliem
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, and Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Akio Oishi
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Philipp L Müller
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | - Philipp Herrmann
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | - Frank G Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | | | - Michael Knapp
- Institute of Medical Biometry, Informatics, and Epidemiology, University of Bonn, Bonn, Germany
| | - Hanno J Bolz
- Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany.,Bioscientia Center for Human Genetics, Ingelheim, Germany
| | - Peter Charbel Issa
- Department of Ophthalmology, University of Bonn, Bonn, Germany.,Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany.,Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, and Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK
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Hanany M, Sharon D. Allele frequency analysis of variants reported to cause autosomal dominant inherited retinal diseases question the involvement of 19% of genes and 10% of reported pathogenic variants. J Med Genet 2019; 56:536-542. [PMID: 30910914 DOI: 10.1136/jmedgenet-2018-105971] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 02/18/2019] [Accepted: 03/03/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Next generation sequencing (NGS) generates a large amount of genetic data that can be used to better characterise disease-causing variants. Our aim was to examine allele frequencies of sequence variants reported to cause autosomal dominant inherited retinal diseases (AD-IRDs). METHODS Genetic information was collected from various databases, including PubMed, the Human Genome Mutation Database, RETNET and gnomAD. RESULTS We generated a database of 1223 variants reported in 58 genes, including their allele frequency in gnomAD that contains NGS data of over 138 000 individuals. While the majority of variants are not represented in gnomAD, 138 had an allele count of >1 and were examined carefully for various aspects including cosegregation and functional analyses. The analysis revealed 122 variants that were reported pathogenic but unlikely to cause AD-IRDs. Interestingly, in some cases, these unlikely pathogenic variants were the only ones reported to cause disease in AD inheritance pattern for a particular gene, therefore raising doubt regarding the involvement of 11 (19%) of the genes in AD-IRDs. CONCLUSION We predict that these data are not limited to a specific disease or inheritance pattern since non-pathogenic variants were mistakenly reported as pathogenic in various diseases. Our results should serve as a warning sign for geneticists, variant database curators and sequencing panels' developers not to automatically accept reported variants as pathogenic but cross-reference the information with large databases.
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Affiliation(s)
- Mor Hanany
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Sharon
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Cehajic-Kapetanovic J, Cottriall CL, Jolly JK, Shanks M, Clouston P, Charbel Issa P, MacLaren RE. Electrophysiological verification of enhanced S-cone syndrome caused by a novel c.755T>C NR2E3 missense variant. Ophthalmic Genet 2019; 40:29-33. [PMID: 30466340 DOI: 10.1080/13816810.2018.1547912] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND Nuclear hormone receptor gene, NR2E3, plays a critical role in retinogenesis and determination of the rod photoreceptor phenotype. Mutations in NR2E3 typically lead to recessive enhanced S-cone syndrome (ESCS), where affected individuals show higher sensitivity to short wavelength light and early onset rod dysfunction. Patients with ESCS present in early childhood with nyctalopia, enhanced sensitivity to blue light and display a very heterogeneic retinal phenotype with varying degrees of clumped pigmentation and occasional retinoschisis. PURPOSE To confirm the pathogenicity of a novel mutation in NR2E3 using electrophysiological studies. MATERIALS AND METHODS Patient underwent detailed clinical evaluation and ophthalmic imaging followed by next generation sequencing analysis and electrophysiological studies. RESULTS We describe a case of a young man of Greek descent with a family history of retinal degeneration. His fundal features at presentation were atypical of ESCS, with striking macular involvement in both eyes, including fibrotic subretinal material overlying the pigment epithelial detachment in one eye and schisis in the other. Genetic testing revealed a novel homozygous variant in NR2E3 gene of uncertain pathogenicity. Instead of performing further genetic analyses, electrophysiological studies showed pathognomonic changes in the S-cone response. CONCLUSIONS With the recent clinical endorsement of a gene therapy for RPE65 related-inherited retinal degeneration it is of paramount importance to correctly identify the pathogenic genetic mutation. In this particular syndrome, we highlight the value of electrophysiology to confirm the pathogenicity of a novel mutation in NR2E3 and aid the diagnosis of ESCS, with potential for gene therapy in the future.
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Affiliation(s)
- Jasmina Cehajic-Kapetanovic
- a Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , Oxford University , Oxford , UK
- b Oxford Eye Hospital , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Charles L Cottriall
- a Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , Oxford University , Oxford , UK
- b Oxford Eye Hospital , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Jasleen K Jolly
- a Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , Oxford University , Oxford , UK
- b Oxford Eye Hospital , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Morag Shanks
- c Oxford Medical Genetics Laboratories , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Penny Clouston
- c Oxford Medical Genetics Laboratories , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Peter Charbel Issa
- a Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , Oxford University , Oxford , UK
- b Oxford Eye Hospital , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
| | - Robert E MacLaren
- a Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , Oxford University , Oxford , UK
- b Oxford Eye Hospital , Oxford University Hospitals NHS Foundation Trust , Oxford , UK
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Birtel J, Gliem M, Mangold E, Müller PL, Holz FG, Neuhaus C, Lenzner S, Zahnleiter D, Betz C, Eisenberger T, Bolz HJ, Charbel Issa P. Next-generation sequencing identifies unexpected genotype-phenotype correlations in patients with retinitis pigmentosa. PLoS One 2018; 13:e0207958. [PMID: 30543658 PMCID: PMC6292620 DOI: 10.1371/journal.pone.0207958] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 11/08/2018] [Indexed: 12/13/2022] Open
Abstract
Retinitis pigmentosa (RP) is an inherited degenerative disease causing severe retinal dystrophy and visual impairment mainly with onset in infancy or adolescence. Targeted next-generation sequencing (NGS) has become an efficient tool to encounter the enormous genetic heterogeneity of diverse retinal dystrophies, including RP. To identify disease-causing mutations in unselected, consecutive RP patients, we conducted Sanger sequencing of genes commonly involved in the suspected genetic RP subtype, followed by targeted large-panel NGS if no mutation was identified, or NGS as primary analysis. A high (70%) detection rate of disease-causing mutations was achieved in a large cohort of 116 unrelated patients. About half (48%) of the solved RP cases were explained by mutations in four genes: RPGR, EYS, PRPF31 and USH2A. Overall, 110 different mutations distributed across 30 different genes were detected, and 46 of these mutations were novel. A molecular diagnosis was achieved in the majority (82–100%) of patients if the family history was suggestive for a particular mode of inheritance, but only in 60% in cases of sporadic RP. The diagnostic potential of extensive molecular analysis in a routine setting is also illustrated by the identification of unexpected genotype-phenotype correlations for RP patients with mutations in CRX, CEP290, RPGRIP1, MFSD8. Furthermore, we identified numerous mutations in autosomal dominant (PRPF31, PRPH2, CRX) and X-linked (RPGR) RP genes in patients with sporadic RP. Variants in RP2 and RPGR were also found in female RP patients with apparently sporadic or dominant disease. In summary, this study demonstrates that massively parallel sequencing of all known retinal dystrophy genes is a valuable diagnostic approach for RP patients.
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Affiliation(s)
- Johannes Birtel
- Department of Ophthalmology, University of Bonn, Bonn, Germany
- Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | - Martin Gliem
- Department of Ophthalmology, University of Bonn, Bonn, Germany
- Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | | | - Philipp L. Müller
- Department of Ophthalmology, University of Bonn, Bonn, Germany
- Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | - Frank G. Holz
- Department of Ophthalmology, University of Bonn, Bonn, Germany
- Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
| | | | | | | | - Christian Betz
- Bioscientia Center for Human Genetics, Ingelheim, Germany
| | | | - Hanno J. Bolz
- Bioscientia Center for Human Genetics, Ingelheim, Germany
- Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany
| | - Peter Charbel Issa
- Department of Ophthalmology, University of Bonn, Bonn, Germany
- Center for Rare Diseases Bonn (ZSEB), University of Bonn, Bonn, Germany
- Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, and Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Birtel J, Gliem M, Holz FG, Herrmann P. Bildgebung und molekulargenetische Diagnostik zur Charakterisierung von Netzhautdystrophien. Ophthalmologe 2018; 115:1021-1027. [DOI: 10.1007/s00347-018-0779-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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Audo I, Mohand-Said S, Boulanger-Scemama E, Zanlonghi X, Condroyer C, Démontant V, Boyard F, Antonio A, Méjécase C, El Shamieh S, Sahel JA, Zeitz C. MERTK
mutation update in inherited retinal diseases. Hum Mutat 2018; 39:887-913. [DOI: 10.1002/humu.23431] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/22/2018] [Accepted: 03/29/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Isabelle Audo
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
- CHNO des Quinze-Vingts; DHU Sight Restore; INSERM-DGOS CIC1423 Paris France
- University College London Institute of Ophthalmology; London UK
| | - Saddek Mohand-Said
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
- CHNO des Quinze-Vingts; DHU Sight Restore; INSERM-DGOS CIC1423 Paris France
| | - Elise Boulanger-Scemama
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
- Fondation Ophtalmologique Adolphe de Rothschild; Paris France
| | | | | | - Vanessa Démontant
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
| | - Fiona Boyard
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
| | - Aline Antonio
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
| | - Cécile Méjécase
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
| | - Said El Shamieh
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
- Department of Medical Laboratory Technology; Faculty of Health Sciences; Beirut Arab University; Beirut Lebanon
| | - José-Alain Sahel
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
- CHNO des Quinze-Vingts; DHU Sight Restore; INSERM-DGOS CIC1423 Paris France
- University College London Institute of Ophthalmology; London UK
- Fondation Ophtalmologique Adolphe de Rothschild; Paris France
- Académie des Sciences-Institut de France; Paris France. Department of Ophthalmology; University of Pittsburgh Medical School; Pittsburgh Pennsylvania
| | - Christina Zeitz
- Sorbonne Université; INSERM; CNRS; Institut de la Vision; Paris France
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Mustafa AE, Faquih T, Baz B, Kattan R, Al-Issa A, Tahir AI, Imtiaz F, Ramzan K, Al-Sayed M, Alowain M, Al-Hassnan Z, Al-Zaidan H, Abouelhoda M, Al-Mubarak BR, Al Tassan NA. Validation of Ion Torrent TM Inherited Disease Panel with the PGM TM Sequencing Platform for Rapid and Comprehensive Mutation Detection. Genes (Basel) 2018; 9:genes9050267. [PMID: 29789446 PMCID: PMC5977207 DOI: 10.3390/genes9050267] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 05/14/2018] [Accepted: 05/18/2018] [Indexed: 01/02/2023] Open
Abstract
Quick and accurate molecular testing is necessary for the better management of many inherited diseases. Recent technological advances in various next generation sequencing (NGS) platforms, such as target panel-based sequencing, has enabled comprehensive, quick, and precise interrogation of many genetic variations. As a result, these technologies have become a valuable tool for gene discovery and for clinical diagnostics. The AmpliSeq Inherited Disease Panel (IDP) consists of 328 genes underlying more than 700 inherited diseases. Here, we aimed to assess the performance of the IDP as a sensitive and rapid comprehensive gene panel testing. A total of 88 patients with inherited diseases and causal mutations that were previously identified by Sanger sequencing were randomly selected for assessing the performance of the IDP. The IDP successfully detected 93.1% of the mutations in our validation cohort, achieving high overall gene coverage (98%). The sensitivity for detecting single nucleotide variants (SNVs) and short Indels was 97.3% and 69.2%, respectively. IDP, when coupled with Ion Torrent Personal Genome Machine (PGM), delivers comprehensive and rapid sequencing for genes that are responsible for various inherited diseases. Our validation results suggest the suitability of this panel for use as a first-line screening test after applying the necessary clinical validation.
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Affiliation(s)
- Abeer E Mustafa
- Behavioral Genetics Unit, Department of Genetics, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Tariq Faquih
- Department of Genetics, King Faisal Specialist Hospital & Research Centre. P.O. Box 3354, Riyadh 11211, Saudi Arabia.
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Batoul Baz
- Behavioral Genetics Unit, Department of Genetics, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Rana Kattan
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Abdulelah Al-Issa
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Asma I Tahir
- Behavioral Genetics Unit, Department of Genetics, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Faiqa Imtiaz
- Department of Genetics, King Faisal Specialist Hospital & Research Centre. P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Khushnooda Ramzan
- Department of Genetics, King Faisal Specialist Hospital & Research Centre. P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Moeenaldeen Al-Sayed
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Mohammed Alowain
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Zuhair Al-Hassnan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Hamad Al-Zaidan
- Department of Medical Genetics, King Faisal Specialist Hospital & Research Centre, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
| | - Mohamed Abouelhoda
- Department of Genetics, King Faisal Specialist Hospital & Research Centre. P.O. Box 3354, Riyadh 11211, Saudi Arabia.
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Bashayer R Al-Mubarak
- Behavioral Genetics Unit, Department of Genetics, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
| | - Nada A Al Tassan
- Behavioral Genetics Unit, Department of Genetics, King Faisal Specialist Hospital & Research Center, P.O. Box 3354, Riyadh 11211, Saudi Arabia.
- Saudi Human Genome Program, King Abdulaziz City for Science & Technology, Riyadh, Saudi Arabia.
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Clinical and genetic characteristics of 251 consecutive patients with macular and cone/cone-rod dystrophy. Sci Rep 2018; 8:4824. [PMID: 29555955 PMCID: PMC5859282 DOI: 10.1038/s41598-018-22096-0] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/16/2018] [Indexed: 12/14/2022] Open
Abstract
Macular and cone/cone-rod dystrophies (MD/CCRD) demonstrate a broad genetic and phenotypic heterogeneity, with retinal alterations solely or predominantly involving the central retina. Targeted next-generation sequencing (NGS) is an efficient diagnostic tool for identifying mutations in patient with retinitis pigmentosa, which shows similar genetic heterogeneity. To detect the genetic causes of disease in patients with MD/CCRD, we implemented a two-tier procedure consisting of Sanger sequencing and targeted NGS including genes associated with clinically overlapping conditions. Disease-causing mutations were identified in 74% of 251 consecutive MD/CCRD patients (33% of the variants were novel). Mutations in ABCA4, PRPH2 and BEST1 accounted for 57% of disease cases. Further mutations were identified in CDHR1, GUCY2D, PROM1, CRX, GUCA1A, CERKL, MT-TL1, KIF11, RP1L1, MERTK, RDH5, CDH3, C1QTNF5, CRB1, JAG1, DRAM2, POC1B, NPHP1 and RPGR. We provide detailed illustrations of rare phenotypes, including autofluorescence and optical coherence tomography imaging. Targeted NGS also identified six potential novel genotype-phenotype correlations for FAM161A, INPP5E, MERTK, FBLN5, SEMA4A and IMPDH1. Clinical reassessment of genetically unsolved patients revealed subgroups with similar retinal phenotype, indicating a common molecular disease cause in each subgroup.
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43
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Avela K, Sankila EM, Seitsonen S, Kuuluvainen L, Barton S, Gillies S, Aittomäki K. A founder mutation in CERKL is a major cause of retinal dystrophy in Finland. Acta Ophthalmol 2018; 96:183-191. [PMID: 29068140 DOI: 10.1111/aos.13551] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 06/28/2017] [Indexed: 11/30/2022]
Abstract
PURPOSE To study the genetic aetiology of retinal dystrophies (RD) in Finnish patients. METHODS A targeted next-generation sequencing (NGS) panel of 105 retinal dystrophy genes was used in a cohort of 55 RD patients. RESULTS The overall diagnostic yield was 60% demonstrating the power of this approach. Interestingly, a missense mutation c.375C>G p.(Cys125Trp) in the CERKL gene was found in 18% of the patients in either a homozygous or compound heterozygous state. Data from Exome Aggregation Consortium (ExAC) Browser show that the CERKL c.375C>G p.(Cys125Trp) allele is enriched in the Finnish population and thus is a founder mutation. Furthermore, we report the clinical picture of 18 patients with mutations in the CERKL gene. CERKL mutations cause a macular-onset disease, in which symptoms first become apparent at the second decade. We also detected other novel founder mutations in the CERKL, EYS, RP1, ABCA4 and GUCY2D genes. CONCLUSION Our report indicates that the first diagnostic test for Finnish patients with sporadic or autosomal recessive RD should be a targeted test for founder mutations in the CERKL, EYS, RP1, ABCA4 and GUCY2D genes. These results confirm the utility of NGS-based gene panels as a powerful method for mutation identification in RD, thus enabling improved genetic counselling for these families.
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Affiliation(s)
- Kristiina Avela
- Department of Clinical Genetics; Helsinki University Hospital; Helsinki Finland
| | - Eeva-Marja Sankila
- Department of Ophthalmology; Helsinki University Hospital; Helsinki Finland
| | - Sanna Seitsonen
- Department of Ophthalmology; Helsinki University Hospital; Helsinki Finland
| | - Liina Kuuluvainen
- Department of Clinical Genetics; Helsinki University Hospital; Helsinki Finland
| | - Stephanie Barton
- St Mary's Hospital; Central Manchester University Hospitals and Manchester Centre for Genomic Medicine; Manchester UK
| | - Stuart Gillies
- St Mary's Hospital; Central Manchester University Hospitals and Manchester Centre for Genomic Medicine; Manchester UK
| | - Kristiina Aittomäki
- Department of Clinical Genetics; Helsinki University Hospital; Helsinki Finland
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44
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Nanda A, Salvetti AP, Martinez-Fernandez de la Camara C, MacLaren RE. Misdiagnosis of X-linked retinitis pigmentosa in a choroideremia patient with heavily pigmented fundi. Ophthalmic Genet 2018; 39:380-383. [PMID: 29377744 DOI: 10.1080/13816810.2018.1430242] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Inherited retinal diseases are thought to be the leading cause of sight loss in the working age population. Mutations found in the RPGR and CHM genes cause retinitis pigmentosa (RP) and choroideremia, respectively. In the first instance, an X-linked family history of visual field loss commonly raises the suspicion of one of these two genes. In choroideremia, the classic description of a white fundal reflex secondary to the widespread chorioretinal degeneration was made over a hundred years ago in Caucasians. But, it is not so obvious in heavily pigmented fundi. Hence, the clinical diagnosis of CHM in non-Caucasian patients may be challenging in the first stages of the disease. Here we report a case of a Southeast Asian gentleman who has a family history of X-linked retinal degeneration and was found to have a confirmed in-frame deletion of 12 DNA nucleotides in exon 15 of the RPGR gene. Later in life, however, his fundal appearance showed unusual areas of circular pigment hypertrophy and clumping. He was therefore tested for carrying a disease-causing mutation in the CHM gene and a null mutation was found. Since gene therapy trials are ongoing for both of these conditions, it has now become critically important to establish the correct genetic diagnosis in order to recruit suitable candidates. Moreover, this case demonstrates the necessity to remain vigilant in the interpretation of genetic results which are inconsistent with clinical features.
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Affiliation(s)
- A Nanda
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom
| | - A P Salvetti
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom.,b Eye 5 Clinic, Sacco Hospital, University of Milan , Milano , Italy
| | | | - R E MacLaren
- a Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, John Radcliffe Hospital , Oxford , United Kingdom.,c Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences , University of Oxford , Oxford , United Kingdom
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45
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Gavan SP, Thompson AJ, Payne K. The economic case for precision medicine. EXPERT REVIEW OF PRECISION MEDICINE AND DRUG DEVELOPMENT 2018; 3:1-9. [PMID: 29682615 PMCID: PMC5890303 DOI: 10.1080/23808993.2018.1421858] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/22/2017] [Indexed: 11/17/2022]
Abstract
Introduction: The advancement of precision medicine into routine clinical practice has been highlighted as an agenda for national and international health care policy. A principle barrier to this advancement is in meeting requirements of the payer or reimbursement agency for health care. This special report aims to explain the economic case for precision medicine, by accounting for the explicit objectives defined by decision-makers responsible for the allocation of limited health care resources. Areas covered: The framework of cost-effectiveness analysis, a method of economic evaluation, is used to describe how precision medicine can, in theory, exploit identifiable patient-level heterogeneity to improve population health outcomes and the relative cost-effectiveness of health care. Four case studies are used to illustrate potential challenges when demonstrating the economic case for a precision medicine in practice. Expert commentary: The economic case for a precision medicine should be considered at an early stage during its research and development phase. Clinical and economic evidence can be generated iteratively and should be in alignment with the objectives and requirements of decision-makers. Programmes of further research, to demonstrate the economic case of a precision medicine, can be prioritized by the extent that they reduce the uncertainty expressed by decision-makers.
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Affiliation(s)
- Sean P. Gavan
- Manchester Centre for Health Economics, Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Alexander J. Thompson
- Manchester Centre for Health Economics, Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Katherine Payne
- Manchester Centre for Health Economics, Division of Population Health, Health Services Research and Primary Care, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
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46
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Imani S, Ijaz I, Shasaltaneh MD, Fu S, Cheng J, Fu J. Molecular genetics characterization and homology modeling of the CHM gene mutation: A study on its association with choroideremia. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2018; 775:39-50. [DOI: 10.1016/j.mrrev.2018.02.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/21/2018] [Accepted: 02/13/2018] [Indexed: 12/19/2022]
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47
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Messchaert M, Haer-Wigman L, Khan MI, Cremers FPM, Collin RWJ. EYS mutation update: In silico assessment of 271 reported and 26 novel variants in patients with retinitis pigmentosa. Hum Mutat 2017; 39:177-186. [PMID: 29159838 DOI: 10.1002/humu.23371] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 11/07/2017] [Accepted: 11/12/2017] [Indexed: 01/22/2023]
Abstract
Mutations in Eyes shut homolog (EYS) are one of the most common causes of autosomal recessive (ar) retinitis pigmentosa (RP), a progressive blinding disorder. The exact function of the EYS protein and the pathogenic mechanisms underlying EYS-associated RP are still poorly understood, which hampers the interpretation of the causality of many EYS variants discovered to date. We collected all reported EYS variants present in 377 arRP index cases published before June 2017, and uploaded them in the Leiden Open Variation Database (www.LOVD.nl/EYS). We also describe 36 additional index cases, carrying 26 novel variants. Of the 297 unique EYS variants identified, almost half (n = 130) are predicted to result in premature truncation of the EYS protein. Classification of all variants using the American College of Medical Genetics and Genomics guidelines revealed that the predicted pathogenicity of these variants cover the complete spectrum ranging from likely benign to pathogenic, although especially missense variants largely fall in the category of uncertain significance. Besides the identification of likely benign alleles previously reported as being probably pathogenic, our comprehensive analysis underscores the need of functional assays to assess the causality of EYS variants, in order to improve molecular diagnostics and counseling of patients with EYS-associated RP.
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Affiliation(s)
- Muriël Messchaert
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Lonneke Haer-Wigman
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Muhammad I Khan
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rob W J Collin
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
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48
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Cheng L, Yu H, Jiang Y, He J, Pu S, Li X, Zhang L. Identification of a novel MYO7A mutation in Usher syndrome type 1. Oncotarget 2017; 9:2295-2303. [PMID: 29416772 PMCID: PMC5788640 DOI: 10.18632/oncotarget.23408] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 12/05/2017] [Indexed: 12/30/2022] Open
Abstract
Usher syndrome (USH) is an autosomal recessive disease characterized by deafness and retinitis pigmentosa. In view of the high phenotypic and genetic heterogeneity in USH, performing genetic screening with traditional methods is impractical. In the present study, we carried out targeted next-generation sequencing (NGS) to uncover the underlying gene in an USH family (2 USH patients and 15 unaffected relatives). One hundred and thirty-five genes associated with inherited retinal degeneration were selected for deep exome sequencing. Subsequently, variant analysis, Sanger validation and segregation tests were utilized to identify the disease-causing mutations in this family. All affected individuals had a classic USH type I (USH1) phenotype which included deafness, vestibular dysfunction and retinitis pigmentosa. Targeted NGS and Sanger sequencing validation suggested that USH1 patients carried an unreported splice site mutation, c.5168+1G>A, as a compound heterozygous mutation with c.6070C>T (p.R2024X) in the MYO7A gene. A functional study revealed decreased expression of the MYO7A gene in the individuals carrying heterozygous mutations. In conclusion, targeted next-generation sequencing provided a comprehensive and efficient diagnosis for USH1. This study revealed the genetic defects in the MYO7A gene and expanded the spectrum of clinical phenotypes associated with USH1 mutations.
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Affiliation(s)
- Ling Cheng
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China.,Department of Ophthalmology, Yongchuan Hospital, Chongqing Medical University, Chongqing, P. R. China
| | - Hongsong Yu
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China.,Department of Immunology, Special Key Laboratory of Gene Detection & Therapy of Guizhou Province, Zunyi Medical University, Guizhou, P. R. China
| | - Yan Jiang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China
| | - Juan He
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China
| | - Sisi Pu
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China
| | - Xin Li
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China
| | - Li Zhang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Ophthalmology and Chongqing Eye Institute, Chongqing, P. R. China
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49
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Farrar GJ, Carrigan M, Dockery A, Millington-Ward S, Palfi A, Chadderton N, Humphries M, Kiang AS, Kenna PF, Humphries P. Toward an elucidation of the molecular genetics of inherited retinal degenerations. Hum Mol Genet 2017; 26:R2-R11. [PMID: 28510639 PMCID: PMC5886474 DOI: 10.1093/hmg/ddx185] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 05/08/2017] [Indexed: 02/06/2023] Open
Abstract
While individually classed as rare diseases, hereditary retinal degenerations (IRDs) are the major cause of registered visual handicap in the developed world. Given their hereditary nature, some degree of intergenic heterogeneity was expected, with genes segregating in autosomal dominant, recessive, X-linked recessive, and more rarely in digenic or mitochondrial modes. Today, it is recognized that IRDs, as a group, represent one of the most genetically diverse of hereditary conditions - at least 260 genes having been implicated, with 70 genes identified in the most common IRD, retinitis pigmentosa (RP). However, targeted sequencing studies of exons from known IRD genes have resulted in the identification of candidate mutations in only approximately 60% of IRD cases. Given recent advances in the development of gene-based medicines, characterization of IRD patient cohorts for known IRD genes and elucidation of the molecular pathologies of disease in those remaining unresolved cases has become an endeavor of the highest priority. Here, we provide an outline of progress in this area.
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Affiliation(s)
- G Jane Farrar
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Matthew Carrigan
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Adrian Dockery
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Sophia Millington-Ward
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Arpad Palfi
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Naomi Chadderton
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Marian Humphries
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Anna Sophia Kiang
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
| | - Paul F Kenna
- Research Foundation, Royal Victoria Eye and Ear Hospital, Dublin 2, Ireland
| | - Pete Humphries
- Institute of Genetics, School of Genetics and Microbiology, University of Dublin, Trinity College, Dublin 2, Ireland
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50
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Abeshi A, Precone V, Beccari T, Dundar M, Falsini B, Bertelli M. Genetic testing in translational ophthalmology. EUROBIOTECH JOURNAL 2017. [DOI: 10.24190/issn2564-615x/2017/s1.01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
Inherited eye diseases are a group of conditions with genetic and phenotypic heterogeneity. Advances in ocular genetic research have provided insights into the genetic basis of many eye diseases. Genetic and technological progress is improving the management and care of patients with inherited eye diseases. Diagnostic laboratories continue to develop strategies with high specificity and sensitivity that reduce the costs and time required for genetic testing. The introduction of next generation sequencing technologies has significantly advanced the identification of new gene candidates and has expanded the scope of genetic testing. Gene therapy offers an important opportunity to target causative genetic mutations. There are clinical trials of treatments involving vector-based eye gene therapies, and a significant number of loci and genes now have a role in the diagnosis and treatment of human eye diseases. Applied genetic technology heralds the development of individualized treatments, ushering ophthalmology into the field of personalized medicine. Many therapeutic strategies have demonstrated efficacy in preclinical studies and have entered the clinical trial phase. In this paper we review the topic of genetic testing in inherited eye diseases. We provide some background information about genetic counseling and genetic testing in ophthalmology and discuss how genetic testing can be helpful to patients and families with inherited eye diseases.
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Affiliation(s)
- Andi Abeshi
- MAGI Balkans, Tirana , Albania
- MAGI’S Lab, Rovereto , Italy
| | | | - Tommaso Beccari
- Department of Pharmaceutical Sciences, University of Perugia, Perugia , Italy
| | - Munis Dundar
- Department of Medical Genetics, Erciyes University Medical School, Kayseri , Turkey
| | - Benedetto Falsini
- Department of Ophthalmology, Catholic University of Rome, Rome , Italy
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