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Vaché C, Faugère V, Baux D, Mansard L, Van Goethem C, Dhaenens CM, Grunewald O, Audo I, Zeitz C, Meunier I, Bocquet B, Cossée M, Bergougnoux A, Kalatzis V, Roux AF. Validation of Nanopore long-read sequencing to resolve RPGR ORF15 genotypes in individuals with X-linked retinitis pigmentosa. Eur J Hum Genet 2024:10.1038/s41431-024-01649-0. [PMID: 38969740 DOI: 10.1038/s41431-024-01649-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 03/15/2024] [Accepted: 06/11/2024] [Indexed: 07/07/2024] Open
Abstract
X-linked retinitis pigmentosa (XLRP) is characterized by progressive vision loss leading to legal blindness in males and a broad severity spectrum in carrier females. Pathogenic alterations of the retinitis pigmentosa GTPase regulator gene (RPGR) are responsible for over 70% of XLRP cases. In the retina, the RPGRORF15 transcript includes a terminal exon, called ORF15, that is altered in the large majority of RPGR-XLRP cases. Unfortunately, due to its highly repetitive sequence, ORF15 represents a considerable challenge in terms of sequencing for molecular diagnostic laboratories. However, in a recent preliminary work Yahya et al. reported a long-read sequencing approach seeming promising. Here, the aim of the study was to validate and integrate this new sequencing strategy in a routine screening workflow. For that purpose, we performed a masked test on 52 genomic DNA samples from male and female individuals carrying 32 different pathogenic ORF15 variations including 20 located in the highly repetitive region of the exon. For the latter, we have obtained a detection rate of 80-85% in males and 60-80% in females after bioinformatic analyses. These numbers raised to 100% for both status after adding a complementary visual inspection of ORF15 long-reads. In accordance with these results, and considering the frequency of ORF15 pathogenic variations in XLRP, we suggest that a long-read screening of ORF15 should be systematically considered before any other sequencing approach in subjects with a diagnosis compatible with XLRP.
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Affiliation(s)
- Christel Vaché
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France.
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France.
| | - Valérie Faugère
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - David Baux
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
- Montpellier BioInformatique pour le Diagnostic Clinique (MOBIDIC), CHU Montpellier, Montpellier, France
| | - Luke Mansard
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
| | - Charles Van Goethem
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- Montpellier BioInformatique pour le Diagnostic Clinique (MOBIDIC), CHU Montpellier, Montpellier, France
| | - Claire-Marie Dhaenens
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience and Cognition, Lille, France
| | - Olivier Grunewald
- Univ. Lille, Inserm, CHU Lille, U1172-LilNCog-Lille Neuroscience and Cognition, Lille, France
| | - Isabelle Audo
- Sorbonne Université, Inserm, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, Centre de Référence Maladies Rares REFERET, Inserm-DGOS CIC1423, Paris, France
| | - Christina Zeitz
- Sorbonne Université, Inserm, CNRS, Institut de la Vision, Paris, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
- National Reference Center for Inherited Sensory Diseases, Univ Montpellier, CHU, Montpellier, France
| | - Béatrice Bocquet
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
- National Reference Center for Inherited Sensory Diseases, Univ Montpellier, CHU, Montpellier, France
| | - Mireille Cossée
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- PhyMedExp, Univ Montpellier, Inserm, CNRS, Montpellier, France
| | - Anne Bergougnoux
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- PhyMedExp, Univ Montpellier, Inserm, CNRS, Montpellier, France
| | - Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
- National Reference Center for Inherited Sensory Diseases, Univ Montpellier, CHU, Montpellier, France
| | - Anne-Françoise Roux
- Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier (INM), Univ Montpellier, Inserm, Montpellier, France
- GCS AURAGEN, Lyon, France
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Chan J, Holdstock J, Shovelton J, Reid J, Speight G, Molha D, Pullabhatla V, Carpenter S, Uddin E, Washio T, Sato H, Izumi Y, Watanabe R, Niiro H, Fukushima Y, Ashida N, Hirose T, Maeda A. Clinical and analytical validation of an 82-gene comprehensive genome-profiling panel for identifying and interpreting variants responsible for inherited retinal dystrophies. PLoS One 2024; 19:e0305422. [PMID: 38870140 PMCID: PMC11175448 DOI: 10.1371/journal.pone.0305422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 05/30/2024] [Indexed: 06/15/2024] Open
Abstract
Inherited retinal dystrophies comprise a clinically complex and heterogenous group of diseases characterized by visual impairment due to pathogenic variants of over 300 different genes. Accurately identifying the causative gene and associated variant is crucial for the definitive diagnosis and subsequent selection of precise treatments. Consequently, well-validated genetic tests are required in the clinical practice. Here, we report the analytical and clinical validation of a next-generation sequencing targeted gene panel, the PrismGuide IRD Panel System. This system enables comprehensive genome profiling of 82 genes related to inherited retinal dystrophies. The PrismGuide IRD Panel System demonstrated 100% (n = 43) concordance with Sanger sequencing in detecting single-nucleotide variants, small insertions, and small deletions in the target genes and also in assessing their zygosity. It also identified copy-number loss in four out of five cases. When assessing precision, we evaluated the reproducibility of variant detection with 2,160 variants in 144 replicates and found 100% agreement in terms of single-nucleotide variants (n = 1,584) and small insertions and deletions (n = 576). Furthermore, the PrismGuide IRD Panel System generated sufficient read depth for variant calls across the purine-rich and highly repetitive open-reading frame 15 region of RPGR and detected all five variants tested. These results show that the PrismGuide IRD Panel System can accurately and consistently detect single-nucleotide variants and small insertions and deletions. Thus, the PrismGuide IRD Panel System could serve as useful tool that is applicable in clinical practice for identifying the causative genes based on the detection and interpretation of variants in patients with inherited retinal dystrophies and can contribute to a precise molecular diagnosis and targeted treatments.
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Affiliation(s)
- Jacqueline Chan
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Jolyon Holdstock
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - John Shovelton
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - James Reid
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Graham Speight
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Duarte Molha
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Venu Pullabhatla
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Stephanie Carpenter
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Ezam Uddin
- Oxford Gene Technology Operations Limited, Kidlington, Oxfordshire, United Kingdom
| | - Takanori Washio
- Life Innovation Center, Riken Genesis Co. LTD, Kawasaki, Kanagawa, Japan
- Division of Clinical Cancer Genomics, Hokkaido University Hospital, Sapporo, Hokkaido, Japan
| | - Hiroko Sato
- Life Innovation Center, Riken Genesis Co. LTD, Kawasaki, Kanagawa, Japan
| | - Yuuki Izumi
- Technology Innovation, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Reiko Watanabe
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Hayato Niiro
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | | | - Naoko Ashida
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Takashi Hirose
- Medical & Scientific Affairs, Sysmex Corporation, Kobe, Hyogo, Japan
| | - Akiko Maeda
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Hyogo, Japan
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Kolawole OU, Huang A, Gregory-Evans CY, Shunmugam M, Weaver T, Gregory-Evans K. Molecular genetic diagnostics for inherited retinal dystrophies in the clinical setting. CANADIAN JOURNAL OF OPHTHALMOLOGY 2023:S0008-4182(23)00256-9. [PMID: 37678418 DOI: 10.1016/j.jcjo.2023.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 08/13/2023] [Accepted: 08/17/2023] [Indexed: 09/09/2023]
Abstract
OBJECTIVE To evaluate the success of diagnostic genetic testing in inherited retinal dystrophy (IRD) patients in the clinical setting. DESIGN Retrospective cohort analysis. PARTICIPANTS A total of 446 consecutive participants from diverse ethnic backgrounds living in western Canada. METHODS Clinical information was collected from participants, including family history, and they underwent a full ophthalmic examination with chart review. Those with a suspected IRD were offered panel-based genetic testing of 351 genes between March 1, 2019, and February 28, 2022. The main outcome measure was effect of the genetic testing results on clinical diagnosis. RESULTS Genetic testing established a conclusive molecular diagnosis in 249 of 446 cases (55.8%), a clearly negative result in 90 of 446 cases (20.1%), and an inconclusive diagnosis in 108 of 446 cases (24.2%). Conclusive disease-causing variants were identified in 69 genes, and the most commonly affected genes were ABCA4 (31 variants), USH2A (25 variants), and RPGR (19 variants). The inconclusive group included likely novel autosomal dominant variants or a pathogenic variant with a variant of uncertain significance in the same gene for a recessive phenotype. Notably, an inconclusive molecular genetic diagnosis was seen in as many as 47.3% of East Asian participants with an outer retinal dystrophy. CONCLUSIONS This study represents the largest review of molecular genetic testing in IRDs in Canada. That negative or inconclusive results obtained in approximately 45% of cases demonstrates that there is an important need for new research into molecular genetic causes of IRDs. This is particularly true in addressing the problem of interpreting a variant of uncertain significance in ethnic minorities.
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Affiliation(s)
- Olubayo U Kolawole
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC
| | - Albert Huang
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC
| | - Cheryl Y Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC
| | - Maheshver Shunmugam
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC
| | - Travers Weaver
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC
| | - Kevin Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC..
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Yahya S, Watson CM, Carr I, McKibbin M, Crinnion LA, Taylor M, Bonin H, Fletcher T, El-Asrag ME, Ali M, Toomes C, Inglehearn CF. Long-Read Nanopore Sequencing of RPGR ORF15 is Enhanced Following DNase I Treatment of MinION Flow Cells. Mol Diagn Ther 2023; 27:525-535. [PMID: 37284979 PMCID: PMC10299921 DOI: 10.1007/s40291-023-00656-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2023] [Indexed: 06/08/2023]
Abstract
INTRODUCTION RPGR ORF15 is an exon present almost exclusively in the retinal transcript of RPGR. It is purine-rich, repetitive and notoriously hard to sequence, but is a hotspot for mutations causing X-linked retinitis pigmentosa. METHODS Long-read nanopore sequencing on MinION and Flongle flow cells was used to sequence RPGR ORF15 in genomic DNA from patients with inherited retinal dystrophy. A flow cell wash kit was used on a MinION flow cell to increase yield. Findings were confirmed by PacBio SMRT long-read sequencing. RESULTS We showed that long-read nanopore sequencing successfully reads through a 2 kb PCR-amplified fragment containing ORF15. We generated reads of sufficient quality and cumulative read-depth to detect pathogenic RP-causing variants. However, we observed that this G-rich, repetitive DNA segment rapidly blocks the available pores, resulting in sequence yields less than 5% of the expected output. This limited the extent to which samples could be pooled, increasing cost. We tested the utility of a MinION wash kit containing DNase I to digest DNA fragments remaining on the flow cell, regenerating the pores. Use of the DNase I treatment allowed repeated re-loading, increasing the sequence reads obtained. Our customised workflow was used to screen pooled amplification products from previously unsolved inherited retinal disease (IRD) in patients, identifying two new cases with pathogenic ORF15 variants. DISCUSSION We report the novel finding that long-read nanopore sequencing can read through RPGR-ORF15, a DNA sequence not captured by short-read next-generation sequencing (NGS), but with a more reduced yield. Use of a flow cell wash kit containing DNase I unblocks the pores, allowing reloading of further library aliquots over a 72-h period, increasing yield. The workflow we describe provides a novel solution to the need for a rapid, robust, scalable, cost-effective ORF15 screening protocol.
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Affiliation(s)
- Samar Yahya
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Medical Genetics, School of Medicine, King Abdulaziz University, Rabigh, Kingdom of Saudi Arabia
| | - Christopher M Watson
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- North East and Yorkshire Genomic Laboratory Hub, Central Lab, St. James's University Hospital, Leeds, UK
| | - Ian Carr
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Martin McKibbin
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Ophthalmology, St. James's University Hospital, Leeds, UK
| | - Laura A Crinnion
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Morag Taylor
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Hope Bonin
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester, UK
| | - Tracy Fletcher
- North West Genomic Laboratory Hub, Manchester Centre for Genomic Medicine, St Mary's Hospital, Manchester, UK
| | - Mohammed E El-Asrag
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
- Department of Zoology, Faculty of Science, Benha University, Banha, Egypt
- Institute of Cancer and Genomic Science, University of Birmingham, Birmingham, UK
| | - Manir Ali
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Carmel Toomes
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK
| | - Chris F Inglehearn
- Leeds Institute of Medical Research, School of Medicine, University of Leeds, St James's University Hospital, Wellcome Trust Brenner Building, Beckett Street, Leeds, LS9 7TF, UK.
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Tuupanen S, Gall K, Sistonen J, Saarinen I, Kämpjärvi K, Wells K, Merkkiniemi K, von Nandelstadh P, Sarantaus L, Känsäkoski J, Mårtenson E, Västinsalo H, Schleit J, Sankila EM, Kere A, Junnila H, Siivonen P, Andreevskaya M, Kytölä V, Muona M, Salmenperä P, Myllykangas S, Koskenvuo J, Alastalo TP. Prevalence of RPGR-Mediated Retinal Dystrophy in an Unselected Cohort of Over 5000 Patients. Transl Vis Sci Technol 2022; 11:6. [PMID: 34985506 PMCID: PMC8742508 DOI: 10.1167/tvst.11.1.6] [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 Comprehensive genetic testing for inherited retinal dystrophy (IRD) is challenged by difficult-to-sequence genomic regions, which are often mutational hotspots, such as RPGR ORF15. The purpose of this study was to evaluate the diagnostic contribution of RPGR variants in an unselected IRD patient cohort referred for testing in a clinical diagnostic laboratory. Methods A total of 5201 consecutive patients were analyzed with a clinically validated next-generation sequencing (NGS)–based assay, including the difficult-to-sequence RPGR ORF15 region. Copy number variant (CNV) detection from NGS data was included. Variant interpretation was performed per the American College of Medical Genetics and Genomics guidelines. Results A confirmed molecular diagnosis in RPGR was found in 4.5% of patients, 24.0% of whom were females. Variants in ORF15 accounted for 74% of the diagnoses; 29% of the diagnostic variants were in the most difficult-to-sequence central region of ORF15 (c.2470-3230). Truncating variants made up the majority (91%) of the diagnostic variants. CNVs explained 2% of the diagnostic cases, of which 80% were one- or two-exon deletions outside of ORF15. Conclusions Our findings indicate that high-throughput, clinically validated NGS-based testing covering the difficult-to-sequence region of ORF15, in combination with high-resolution CNV detection, can help to maximize the diagnostic yield for patients with IRD. Translational Relevance These results demonstrate an accurate and scalable method for the detection of RPGR-related variants, including the difficult-to-sequence ORF15 hotspot, which is relevant given current and emerging therapeutic opportunities.
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Affiliation(s)
| | | | | | | | | | - Kirsty Wells
- Blueprint Genetics OY, Keilaranta, Espoo, Finland
| | | | | | | | | | | | | | | | - Eeva-Marja Sankila
- Helsinki University Eye Hospital, Outpatient Clinic for Hereditary Eye Diseases, Helsinki, Finland
| | | | | | | | | | - Ville Kytölä
- Blueprint Genetics OY, Keilaranta, Espoo, Finland
| | - Mikko Muona
- Blueprint Genetics OY, Keilaranta, Espoo, Finland
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Pulido JS, Procopio R, Davila HJ, Bello N, Ku C, Pennesi ME, Yang P, Nagiel A, Mahroo OA, Aleman TS, Salido EM, Reynolds M. Inherited Retinal Disease Panels-Caveat Emptor-Truly Know Your Inherited Retinal Disease Panel. Retina 2022; 42:1-3. [PMID: 34690342 PMCID: PMC8702468 DOI: 10.1097/iae.0000000000003319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Jose S Pulido
- Department of Ophthalmology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota
| | - Rebecca Procopio
- Department of Ophthalmology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Hiram J Davila
- Department of Ophthalmology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Nicholas Bello
- Department of Ophthalmology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Cristy Ku
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon
| | - Mark E Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon
| | - Aaron Nagiel
- The Vision Center, Children's Hospital Los Angeles, USC Roski Eye Institute, Keck School of Medicine University of Southern California, Los Angeles, California
| | - Omar A Mahroo
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
- Department of Ophthalmology, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
- Section of Ophthalmology, King's College London, London, United Kingdom
- Physiology, Development, and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Tomas S Aleman
- Department of Ophthalmology, Scheie Eye Institute at the Perelman Center for Advance Medicine and the Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
- The Children's Hospital of Philadelphia (CHOP), Philadelphia, Pennsylvania
| | - Ezequiel M Salido
- Department of Biochemistry, Ophthalmology, and Visual Sciences, West Virginia University, Morgantown, West Virginia; and
| | - Margaret Reynolds
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis, St. Louis, Missouri
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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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Tang J, Tan M, Deng Y, Tang H, Shi H, Li M, Ma W, Li J, Dai H, Li J, Zhou S, Li X, Wei F, Ma X, Luo L. Two Novel Pathogenic Variants of TJP2 Gene and the Underlying Molecular Mechanisms in Progressive Familial Intrahepatic Cholestasis Type 4 Patients. Front Cell Dev Biol 2021; 9:661599. [PMID: 34504838 PMCID: PMC8421653 DOI: 10.3389/fcell.2021.661599] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 07/09/2021] [Indexed: 12/13/2022] Open
Abstract
Progressive familial intrahepatic cholestasis (PFIC) is an autosomal recessive inherited disease that accounts for 10%-15% childhood cholestasis and could lead to infant disability or death. There are three well-established types of PFIC (1-3), caused by mutations in the ATP8B1, ABCB11, and ABCB4 genes. Biallelic pathogenic variants in the tight junction protein 2 gene (TJP2) were newly reported as a cause for PFIC type 4; however, only a limited number of patients and undisputable variants have been reported for TJP2, and the underlying mechanism for PFIC 4 remains poorly understood. To explore the diagnostic yield of TJP2 analysis in suspected PFIC patients negative for the PFIC1-3 mutation, we designed a multiplex polymerase chain reaction-based next-generation sequencing method to analyze TJP2 gene variants in 267 PFIC patients and identified biallelic rare variants in three patients, including three known pathogenic variants and two novel variants in three patients. By using CRISPR-cas9 technology, we demonstrated that TJP2 c.1202A > G was pathogenic at least partially by increasing the expression and nuclear localization of TJP2 protein. With the minigene assay, we showed that TJP2 c.2668-11A > G was a new pathogenic variant by inducing abnormal splicing of TJP2 gene and translation of prematurely truncated TJP2 protein. Furthermore, knockdown of TJP2 protein by siRNA technology led to inhibition of cell proliferation, induction of apoptosis, dispersed F-actin, and disordered microfilaments in LO2 and HepG2celles. Global gene expression profiling of TJP2 knockdown LO2 cells and HepG2 cells identified the dysregulated genes involved in the regulation of actin cytoskeleton. Microtubule cytoskeleton genes were significantly downregulated in TJP2 knockdown cells. The results of this study demonstrate that TJP2 c.1202A > G and TJP2 c.2668-11A > G are two novel pathogenic variants and the cytoskeleton-related functions and pathways might be potential molecular pathogenesis for PFIC.
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Affiliation(s)
- Jia Tang
- NHC Key Laboratory of Male Reproduction and Genetics, Guangdong Provincial Reproductive Science Institute (Guangdong Provincial Fertility Hospital), Guangzhou, China
- Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, China
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Meihua Tan
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- BGI Genomics Co., Ltd., Shenzhen, China
| | - Yihui Deng
- Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Hui Tang
- Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Haihong Shi
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, China
| | - Mingzhen Li
- NHC Key Laboratory of Male Reproduction and Genetics, Guangdong Provincial Reproductive Science Institute (Guangdong Provincial Fertility Hospital), Guangzhou, China
| | - Wei Ma
- Department of Biology, School of Basic Medicine, Jiamusi University, Jiamusi, China
| | - Jia Li
- BGI Genomics Co., Ltd., Shenzhen, China
| | - Hongzheng Dai
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Jianli Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Shengmei Zhou
- Department of Pathology and Laboratory Medicine, Children’s Hospital Los Angeles, Los Angeles, CA, United States
| | - Xu Li
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou, China
| | - Fengxiang Wei
- Longgang District Maternity & Child Healthcare Hospital of Shenzhen City, Shenzhen, China
| | - Xiaofen Ma
- Department of Medical Imaging of Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Liangping Luo
- Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
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9
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Di Iorio V, Karali M, Melillo P, Testa F, Brunetti-Pierri R, Musacchia F, Condroyer C, Neidhardt J, Audo I, Zeitz C, Banfi S, Simonelli F. Spectrum of Disease Severity in Patients With X-Linked Retinitis Pigmentosa Due to RPGR Mutations. Invest Ophthalmol Vis Sci 2021; 61:36. [PMID: 33372982 PMCID: PMC7774109 DOI: 10.1167/iovs.61.14.36] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Purpose The purpose of this study was to perform a detailed longitudinal phenotyping of X-linked retinitis pigmentosa (RP) caused by mutations in the RPGR gene during a long follow-up period. Methods An Italian cohort of 48 male patients (from 31 unrelated families) with RPGR-associated RP was clinically assessed at a single center (mean follow-up = 6.5 years), including measurements of best-corrected visual acuity (BCVA), Goldmann visual field (GVF), optical coherence tomography (OCT), fundus autofluorescence (FAF), microperimetry, and full-field electroretinography (ERG). Results Patients (29.6 ± 15.2 years) showed a mean BCVA of 0.6 ± 0.7 logMAR, mostly with myopic refraction (79.2%). Thirty patients (62.5%) presented a typical RP fundus, while the remaining sine pigmento RP. Over the follow-up, BCVA significantly declined at a mean rate of 0.025 logMAR/year. Typical RP and high myopia were associated with a significantly faster decline of BCVA. Blindness was driven primarily by GVF loss. ERG responses with a rod-cone pattern of dysfunction were detectable in patients (50%) that were significantly younger and more frequently presented sine pigmento RP. Thirteen patients (27.1%) had macular abnormalities without cystoid macular edema. Patients (50%) with a perimacular hyper-FAF ring were significantly younger, had a higher BCVA and a better-preserved ellipsoid zone band than those with markedly decreased FAF. Patients harboring pathogenic variants in exons 1 to 14 showed a milder phenotype compared to those with ORF15 mutations. Conclusions Our monocentric, longitudinal retrospective study revealed a spectrum disease progression in male patients with RPGR-associated RP. Slow disease progression correlated with sine pigmento RP, absence of high myopia, and mutations in RPGR exons 1 to 14.
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Affiliation(s)
- Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Marianthi Karali
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy.,Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | - Paolo Melillo
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | | | | | - John Neidhardt
- Human Genetics, Faculty of Medicine and Health Sciences, University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University Oldenburg, Oldenburg, Germany
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC, France.,Institute of Ophthalmology, University College of London, London, United Kingdom
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Medical Genetics, Department of Precision Medicine, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy
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10
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Maggi J, Koller S, Bähr L, Feil S, Kivrak Pfiffner F, Hanson JVM, Maspoli A, Gerth-Kahlert C, Berger W. Long-Range PCR-Based NGS Applications to Diagnose Mendelian Retinal Diseases. Int J Mol Sci 2021; 22:ijms22041508. [PMID: 33546218 PMCID: PMC7913364 DOI: 10.3390/ijms22041508] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/27/2022] Open
Abstract
The purpose of this study was to develop a flexible, cost-efficient, next-generation sequencing (NGS) protocol for genetic testing. Long-range polymerase chain reaction (PCR) amplicons of up to 20 kb in size were designed to amplify entire genomic regions for a panel (n = 35) of inherited retinal disease (IRD)-associated loci. Amplicons were pooled and sequenced by NGS. The analysis was applied to 227 probands diagnosed with IRD: (A) 108 previously molecularly diagnosed, (B) 94 without previous genetic testing, and (C) 25 undiagnosed after whole-exome sequencing (WES). The method was validated with 100% sensitivity on cohort A. Long-range PCR-based sequencing revealed likely causative variant(s) in 51% and 24% of proband from cohorts B and C, respectively. Breakpoints of 3 copy number variants (CNVs) could be characterized. Long-range PCR libraries spike-in extended coverage of WES. Read phasing confirmed compound heterozygosity in 5 probands. The proposed sequencing protocol provided deep coverage of the entire gene, including intronic and promoter regions. Our method can be used (i) as a first-tier assay to reduce genetic testing costs, (ii) to elucidate missing heritability cases, (iii) to characterize breakpoints of CNVs at nucleotide resolution, (iv) to extend WES data to non-coding regions by spiking-in long-range PCR libraries, and (v) to help with phasing of candidate variants.
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Affiliation(s)
- Jordi Maggi
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - Samuel Koller
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - Luzy Bähr
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - Silke Feil
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - Fatma Kivrak Pfiffner
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - James V. M. Hanson
- Department of Ophthalmology, University Hospital Zurich and University of Zurich, 8091 Zurich, Switzerland; (J.V.M.H.); (C.G.-K.)
| | - Alessandro Maspoli
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
| | - Christina Gerth-Kahlert
- Department of Ophthalmology, University Hospital Zurich and University of Zurich, 8091 Zurich, Switzerland; (J.V.M.H.); (C.G.-K.)
| | - Wolfgang Berger
- Institute of Medical Molecular Genetics, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.); (L.B.); (S.F.); (F.K.P.); (A.M.)
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8057 Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), University and ETH Zurich, 8057 Zurich, Switzerland
- Correspondence: ; Tel.: +41-44-556-33-50
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11
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Zou X, Fang S, Wu S, Li H, Sun Z, Zhu T, Wei X, Sui R. Detailed comparison of phenotype between male patients carrying variants in exons 1-14 and ORF15 of RPGR. Exp Eye Res 2020; 198:108147. [PMID: 32702353 DOI: 10.1016/j.exer.2020.108147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 07/05/2020] [Accepted: 07/08/2020] [Indexed: 12/19/2022]
Abstract
PURPOSE To compare disease severity in detail between patients carrying variants in exons 1-14 and ORF15 of retinitis pigmentosa GTPase regulator (RPGR). METHODS Systematic next-generation sequencing data analysis, Sanger sequencing validation and segregation analysis were utilised to identify the pathogenic variants. Detailed ophthalmic examinations, including electroretinograms, fundus photography, fundus autofluorescence and optical coherence tomography were performed. Statistical analysis, including age adjustment and comparison, were performed based on cross-sectional level to compare disease severity between variants in the two RPGR variant groups. RESULTS Sixty-two variants were identified in RPGR in 86 patients from 77 unrelated families. Twenty-nine (37.7%) had variants in RPGR-exons 1-14 (group 1) and 48 (62.3%) in RPGR-ORF15 (group 2). Eighty-four patients were diagnosed with X-linked retinitis pigmentosa and only two patients with cone-rod dystrophy. LogMAR visual acuity increased 0.035 and 0.022 each year on average in group 1 and group 2, respectively. Group 2 patients had better visual acuity with a mean logMAR difference of 0.4378, which is significant after age adjustment (P < 0.01). Neither the value of log (ellipsoid zone width) nor central retinal thickness was significantly correlated with variant grouping after considering the effect of the age variable (P = 0.56 and 0.40, respectively). Spherical refractive error did not differ significantly between the two variant groups (P = 0.17). Patterns of autofluorescence included a hyperfluorescent ring at the posterior pole, diffuse hyperfluorescence in the macular area, and dark macular autofluorescence with or without fovea hyperfluorescence. The age and proportion of fundus autofluorescence patterns between the two variant groups were significantly different (P < 0.01). CONCLUSIONS Patients with variants in exons 1-14 retained less visual acuity than patients with ORF15 variants and deteriorated faster. However, the ellipsoid zone widths, central retinal thickness and refractions were comparable between the two groups. Autofluorescence pattern relates to the age and the variant grouping.
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Affiliation(s)
- Xuan Zou
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Sha Fang
- School of Statistics, Capital University of Economics and Business, Beijing, 100070, China
| | - Shijing Wu
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Hui Li
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Zixi Sun
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Tian Zhu
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Xing Wei
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100730, China.
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12
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Maggi J, Roberts L, Koller S, Rebello G, Berger W, Ramesar R. De Novo Assembly-Based Analysis of RPGR Exon ORF15 in an Indigenous African Cohort Overcomes Limitations of a Standard Next-Generation Sequencing (NGS) Data Analysis Pipeline. Genes (Basel) 2020; 11:genes11070800. [PMID: 32679846 PMCID: PMC7396994 DOI: 10.3390/genes11070800] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 06/24/2020] [Accepted: 07/13/2020] [Indexed: 01/10/2023] Open
Abstract
RPGR exon ORF15 variants are one of the most frequent causes for inherited retinal disorders (IRDs), in particular retinitis pigmentosa. The low sequence complexity of this mutation hotspot makes it prone to indels and challenging for sequence data analysis. Whole-exome sequencing generally fails to provide adequate coverage in this region. Therefore, complementary methods are needed to avoid false positives as well as negative results. In this study, next-generation sequencing (NGS) was used to sequence long-range PCR amplicons for an IRD cohort of African ancestry. By developing a novel secondary analysis pipeline based on de novo assembly, we were able to avoid the miscalling of variants generated by standard NGS analysis tools. We identified pathogenic variants in 11 patients (13% of the cohort), two of which have not been reported previously. We provide a novel and alternative end-to-end secondary analysis pipeline for targeted NGS of ORF15 that is less prone to false positive and negative variant calls.
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Affiliation(s)
- Jordi Maggi
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8006 Zurich, Switzerland
| | - Lisa Roberts
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
| | - Samuel Koller
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
| | - George Rebello
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
| | - Wolfgang Berger
- Institute of Medical Molecular Genetic, University of Zurich, 8952 Schlieren, Switzerland; (J.M.); (S.K.)
- Zurich Center for Integrative Human Physiology (ZIHP), University of Zurich, 8006 Zurich, Switzerland
- Neuroscience Center Zurich (ZNZ), University and ETH Zurich, 8006 Zurich, Switzerland
- Correspondence:
| | - Rajkumar Ramesar
- University of Cape Town/MRC Genomic and Precision Medicine Research Unit, Division of Human Genetics, Department of Pathology, Institute of Infectious Disease and Molecular Medicine (IDM), Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (L.R.); (G.R.); (R.R.)
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13
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Tang J, Zhou C, Shi H, Mo Y, Tan W, Sun T, Zhu J, Li Q, Li H, Li Y, Wang S, Hong Y, Li N, Zeng Q, Tan J, Ma W, Luo L. Prenatal diagnosis of skeletal dysplasias using whole exome sequencing in China. Clin Chim Acta 2020; 507:187-193. [PMID: 32360156 DOI: 10.1016/j.cca.2020.04.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/04/2020] [Accepted: 04/27/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND Skeletal dysplasias account for nearly 10% of fetal structural malformations detected by ultrasonography. This clinically heterogeneous group of genetic anomaly includes at least 461 genetic skeletal disorders with extreme clinical, phenotypic, and genetic heterogeneities, thus, significantly complicates accurate diagnosis. Researches have used whole exome sequencing (WES) for prenatal molecular diagnoses of skeletal dysplasias, however, data are still limited. METHODS DNA extracted from umbilical cord blood or amniocytes from fetuses suspected of skeletal dysplasias based on ultrasound evaluations were analyzed by WES. Blood samples were taken from the parents of the positive fetuses for co-segregation analysis using Sanger sequencing. RESULT Definitive molecular diagnosis was made in 6/8 (75%) cases, comprised of 5 de novo disease-causing changes in 3 genes (FGFR3, COL2A1, and COL1A2) and one proband with a biallelic deficiency for Lamin B Receptor(LBR),and including 3 novel variants. All fetuses had no detectable copy number variation (CNV) from sequencing results. CONCLUSIONS Our study suggests that WES is an efficient approach for prenatal diagnosis of fetuses suspected of skeletal abnormalities and contributes to parental genetics counseling and pregnancy management.
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Affiliation(s)
- Jia Tang
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China; Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, Guangdong 510080, China.
| | - Chenglong Zhou
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China; Halo Genetics, Guangzhou, Guangdong 510000, China
| | - Haihong Shi
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China; Halo Genetics, Guangzhou, Guangdong 510000, China
| | - Yuying Mo
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Weilan Tan
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Tielan Sun
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Jinling Zhu
- Department of Biology, School of Basic Medicine, Jiamusi University, Jiamusi, Heilongjiang 154007, China
| | - Qing Li
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Hui Li
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Yuping Li
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Songbai Wang
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Yan Hong
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Ning Li
- Halo Genetics, Guangzhou, Guangdong 510000, China
| | - Qinlong Zeng
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Jieliang Tan
- Medical Genetics Center, Jiangmen Maternity and Child Health Care Hospital, Jiangmen, Guangdong 529000, China
| | - Wei Ma
- Department of Biology, School of Basic Medicine, Jiamusi University, Jiamusi, Heilongjiang 154007, China
| | - Liangping Luo
- Department of Medical Imaging Center, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, Guangdong 510080, China.
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14
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Whelan L, Dockery A, Wynne N, Zhu J, Stephenson K, Silvestri G, Turner J, O’Byrne JJ, Carrigan M, Humphries P, Keegan D, Kenna PF, Farrar GJ. Findings from a Genotyping Study of Over 1000 People with Inherited Retinal Disorders in Ireland. Genes (Basel) 2020; 11:E105. [PMID: 31963381 PMCID: PMC7016747 DOI: 10.3390/genes11010105] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 12/13/2019] [Accepted: 01/13/2020] [Indexed: 12/15/2022] Open
Abstract
The Irish national registry for inherited retinal degenerations (Target 5000) is a clinical and scientific program to identify individuals in Ireland with inherited retinal disorders and to attempt to ascertain the genetic cause underlying the disease pathology. Potential participants first undergo a clinical assessment, which includes clinical history and analysis with multimodal retinal imaging, electrophysiology, and visual field testing. If suitable for recruitment, a sample is taken and used for genetic analysis. Genetic analysis is conducted by use of a retinal gene panel target capture sequencing approach. With over 1000 participants from 710 pedigrees now screened, there is a positive candidate variant detection rate of approximately 70% (495/710). Where an autosomal recessive inheritance pattern is observed, an additional 9% (64/710) of probands have tested positive for a single candidate variant. Many novel variants have also been detected as part of this endeavor. The target capture approach is an economic and effective means of screening patients with inherited retinal disorders. Despite the advances in sequencing technology and the ever-decreasing associated processing costs, target capture remains an attractive option as the data produced is easily processed, analyzed, and stored compared to more comprehensive methods. However, with decreasing costs of whole genome and whole exome sequencing, the focus will likely move towards these methods for more comprehensive data generation.
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Affiliation(s)
- Laura Whelan
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
| | - Adrian Dockery
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
| | - Niamh Wynne
- The Research Foundation, Royal Victoria Eye and Ear Hospital, D02 XK51 Dublin, Ireland;
| | - Julia Zhu
- Clinical Genetics Centre for Ophthalmology, The Mater Misericordiae University Hospital, D07 R2WY Dublin, Ireland; (J.Z.); (K.S.); (J.T.); (J.J.O.); (D.K.)
| | - Kirk Stephenson
- Clinical Genetics Centre for Ophthalmology, The Mater Misericordiae University Hospital, D07 R2WY Dublin, Ireland; (J.Z.); (K.S.); (J.T.); (J.J.O.); (D.K.)
| | - Giuliana Silvestri
- Department of Ophthalmology, The Royal Victoria Hospital, Belfast BT12 6BA, Northern Ireland, UK;
- Centre for Experimental Medicine, Queen’s University Belfast, Belfast BT7 1NN, Northern Ireland, UK
| | - Jacqueline Turner
- Clinical Genetics Centre for Ophthalmology, The Mater Misericordiae University Hospital, D07 R2WY Dublin, Ireland; (J.Z.); (K.S.); (J.T.); (J.J.O.); (D.K.)
| | - James J. O’Byrne
- Clinical Genetics Centre for Ophthalmology, The Mater Misericordiae University Hospital, D07 R2WY Dublin, Ireland; (J.Z.); (K.S.); (J.T.); (J.J.O.); (D.K.)
| | - Matthew Carrigan
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
| | - Peter Humphries
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
| | - David Keegan
- Clinical Genetics Centre for Ophthalmology, The Mater Misericordiae University Hospital, D07 R2WY Dublin, Ireland; (J.Z.); (K.S.); (J.T.); (J.J.O.); (D.K.)
| | - Paul F. Kenna
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
- The Research Foundation, Royal Victoria Eye and Ear Hospital, D02 XK51 Dublin, Ireland;
| | - G. Jane Farrar
- The School of Genetics & Microbiology, Trinity College Dublin, D02 VF25 Dublin, Ireland; (A.D.); (M.C.); (P.H.); (P.F.K.); (G.J.F.)
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15
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Zenteno JC, García-Montaño LA, Cruz-Aguilar M, Ronquillo J, Rodas-Serrano A, Aguilar-Castul L, Matsui R, Vencedor-Meraz CI, Arce-González R, Graue-Wiechers F, Gutiérrez-Paz M, Urrea-Victoria T, de Dios Cuadras U, Chacón-Camacho OF. Extensive genic and allelic heterogeneity underlying inherited retinal dystrophies in Mexican patients molecularly analyzed by next-generation sequencing. Mol Genet Genomic Med 2019; 8. [PMID: 31736247 PMCID: PMC6978239 DOI: 10.1002/mgg3.1044] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 10/23/2019] [Indexed: 12/27/2022] Open
Abstract
Background Retinal dystrophies (RDs) are one of the most genetically heterogeneous monogenic disorders with ~270 associated loci identified by early 2019. The recent application of next‐generation sequencing (NGS) has greatly improved the molecular diagnosis of RD patients. Genetic characterization of RD cohorts from different ethnic groups is justified, as it would improve the knowledge of molecular basis of the disease. Here, we present the results of genetic analysis in a large cohort of 143 unrelated Mexican subjects with a variety of RDs. Methods A targeted NGS approach covering 199 RD genes was employed for molecular screening of 143 unrelated patients. In addition to probands, 258 relatives were genotyped by Sanger sequencing for familial segregation of pathogenic variants. Results A solving rate of 66% (95/143) was achieved, with evidence of extensive loci (44 genes) and allelic (110 pathogenic variants) heterogeneity. Forty‐eight percent of the identified pathogenic variants were novel while ABCA4, CRB1, USH2A, and RPE65 carried the greatest number of alterations. Novel deleterious variants in IDH3B and ARL6 were identified, supporting their involvement in RD. Familial segregation of causal variants allowed the recognition of 124 autosomal or X‐linked carriers. Conclusion Our results illustrate the utility of NGS for genetic diagnosis of RDs of different populations for a better knowledge of the mutational landscape associated with the disease.
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Affiliation(s)
- Juan C Zenteno
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico.,Department of Biochemistry, Faculty of Medicine, UNAM, Mexico City, Mexico
| | | | - Marisa Cruz-Aguilar
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Josué Ronquillo
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Agustín Rodas-Serrano
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | | | - Rodrigo Matsui
- Department of Retina, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | | | - Rocío Arce-González
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | | | - Mario Gutiérrez-Paz
- Department of Retina, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Tatiana Urrea-Victoria
- Department of Retina, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Ulises de Dios Cuadras
- Department of Retina, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
| | - Oscar F Chacón-Camacho
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico
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Chiang JPW, Lamey TM, Wang NK, Duan J, Zhou W, McLaren TL, Thompson JA, Ruddle J, De Roach JN. Development of High-Throughput Clinical Testing of RPGR ORF15 Using a Large Inherited Retinal Dystrophy Cohort. Invest Ophthalmol Vis Sci 2019; 59:4434-4440. [PMID: 30193314 DOI: 10.1167/iovs.18-24555] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Mutations in the ORF15 region of RPGR account for approximately half of all X-linked retinitis pigmentosa cases. However, a robust high-throughput method for the detection of ORF15 mutations has yet to be validated. We set out to develop the first clinically validated next-generation sequencing (NGS) method for the detection of mutations in this difficult-to-sequence region, including test accuracy and coverage data. Methods As part of a blind-test, 145 research samples, previously tested by Sanger sequencing, and 81 clinical samples were evaluated using NGS of long-range PCR products fragmented with Illumina's Nextera library preparation kit (method 1), or with Centrillion's OneTube technology, supplemented with duplication analysis using an ORF15-specific in-silico array (method 2). DNA fragments were analyzed using Agilent's DNA 1000 assay, and sequencing was done on Illumina's MiSeq 2×150 or HiSeq2500 2×100. NextGENe by SoftGenetics was used for data analysis and variant calling. Results The Nextera library preparation method produced 24 cases of discordance due to (in order of decreasing occurrence) false-negatives, incorrectly called variants, and a false-positive. Subsequent use of a new, OneTube NGS library preparation method, supplemented with duplication analyses, resolved discordance between Sanger and NGS data in all cases. This improvement in variant detection accuracy was largely attributed to improvement in random fragmentation offered by the enzymatic OneTube method, resulting in more complete coverage of the highly repetitive ORF15 region. Minimum coverage was roughly 320 reads for Nextera and 6800 reads for OneTube (normalized for total read counts). Conclusions This paper documents the first clinically validated NGS method for reliable, high-throughput sequencing of RPGR ORF15. Sensitivity and specificity of the new method were 100%, with the caveat of unclear zygosity calling for one large duplication case. These findings demonstrate a reliable and practical implementation for NGS-based diagnosis of RPGR ORF15 mutations. They also provide the foundation for targeted, high-coverage sequencing of any other repetitive regions within the genome.
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Affiliation(s)
- John P W Chiang
- Molecular Vision Laboratory, Hillsboro, Oregon, United States
| | - Tina M Lamey
- Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Western Australia, Australia
| | - Nicholas K Wang
- Molecular Vision Laboratory, Hillsboro, Oregon, United States
| | - Jie Duan
- Molecular Vision Laboratory, Hillsboro, Oregon, United States
| | - Wei Zhou
- Centrillion Technologies, Palo Alto, California, United States
| | - Terri L McLaren
- Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Jennifer A Thompson
- Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | | | - John N De Roach
- Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Western Australia, Australia
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A new approach based on targeted pooled DNA sequencing identifies novel mutations in patients with Inherited Retinal Dystrophies. Sci Rep 2018; 8:15457. [PMID: 30337596 PMCID: PMC6194132 DOI: 10.1038/s41598-018-33810-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 10/04/2018] [Indexed: 01/28/2023] Open
Abstract
Inherited retinal diseases (IRD) are a heterogeneous group of diseases that mainly affect the retina; more than 250 genes have been linked to the disease and more than 20 different clinical phenotypes have been described. This heterogeneity both at the clinical and genetic levels complicates the identification of causative mutations. Therefore, a detailed genetic characterization is important for genetic counselling and decisions regarding treatment. In this study, we developed a method consisting on pooled targeted next generation sequencing (NGS) that we applied to 316 eye disease related genes, followed by High Resolution Melting and copy number variation analysis. DNA from 115 unrelated test samples was pooled and samples with known mutations were used as positive controls to assess the sensitivity of our approach. Causal mutations for IRDs were found in 36 patients achieving a detection rate of 31.3%. Overall, 49 likely causative mutations were identified in characterized patients, 14 of which were first described in this study (28.6%). Our study shows that this new approach is a cost-effective tool for detection of causative mutations in patients with inherited retinopathies.
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Target 5000: Target Capture Sequencing for Inherited Retinal Degenerations. Genes (Basel) 2017; 8:genes8110304. [PMID: 29099798 PMCID: PMC5704217 DOI: 10.3390/genes8110304] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 10/23/2017] [Accepted: 10/27/2017] [Indexed: 01/02/2023] Open
Abstract
There are an estimated 5000 people in Ireland who currently have an inherited retinal degeneration (IRD). It is the goal of this study, through genetic diagnosis, to better enable these 5000 individuals to obtain a clearer understanding of their condition and improved access to potentially applicable therapies. Here we show the current findings of a target capture next-generation sequencing study of over 750 patients from over 520 pedigrees currently situated in Ireland. We also demonstrate how processes can be implemented to retrospectively analyse patient datasets for the detection of structural variants in previously obtained sequencing reads. Pathogenic or likely pathogenic mutations were detected in 68% of pedigrees tested. We report nearly 30 novel mutations including three large structural variants. The population statistics related to our findings are presented by condition and credited to their respective candidate gene mutations. Rediagnosis rates of clinical phenotypes after genotyping are discussed. Possible causes of failure to detect a candidate mutation are evaluated. Future elements of this project, with a specific emphasis on structural variants and non-coding pathogenic variants, are expected to increase detection rates further and thereby produce an even more comprehensive representation of the genetic landscape of IRDs in Ireland.
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Charng J, Cideciyan AV, Jacobson SG, Sumaroka A, Schwartz SB, Swider M, Roman AJ, Sheplock R, Anand M, Peden MC, Khanna H, Heon E, Wright AF, Swaroop A. Variegated yet non-random rod and cone photoreceptor disease patterns in RPGR-ORF15-associated retinal degeneration. Hum Mol Genet 2016; 25:5444-5459. [PMID: 27798110 PMCID: PMC6078602 DOI: 10.1093/hmg/ddw361] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/16/2016] [Accepted: 10/18/2016] [Indexed: 12/13/2022] Open
Abstract
Mutations in the ORF15 exon of the RPGR gene cause a common form of X-linked retinitis pigmentosa, which often results in severe loss of vision. In dogs and mice, gene augmentation therapy has been shown to arrest the progressive degeneration of rod and cone photoreceptors. However, the distribution of potentially treatable photoreceptors across the human retinas and the rate of degeneration are not known. Here, we have defined structural and functional features of the disease in 70 individuals with ORF15 mutations. We also correlated the features observed in patients with those of three Rpgr-mutant (Rpgr-ko, Rd9, and Rpgr-cko) mice. In patients, there was pronounced macular disease. Across the retina, rod and cone dysfunction showed a range of patterns and a spectrum of severity between individuals, but a high symmetry was observed between eyes of each individual. Genotype was not related to disease expression. In the Rpgr-ko mice, there were intra-retinal differences in rhodopsin and cone opsin trafficking. In Rd9 and Rpgr-cko mice, retinal degeneration showed inter-ocular symmetry. Longitudinal results in patients revealed localized rod and cone dysfunction with progression rates of 0.8 to 1.3 log per decade in sensitivity loss. Relatively retained rod and cone photoreceptors in mid- and far-peripheral temporal-inferior and nasal-inferior visual field regions should be good targets for future localized gene therapies in patients.
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Affiliation(s)
- Jason Charng
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Artur V. Cideciyan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Samuel G. Jacobson
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Alexander Sumaroka
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Sharon B. Schwartz
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Malgorzata Swider
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Alejandro J. Roman
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Rebecca Sheplock
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, PA, USA
| | - Manisha Anand
- Department of Ophthalmology, University of Massachusetts Medical School, Worcester, Massachusetts, MA, USA
| | - Marc C. Peden
- Retina Associates of Florida, Tampa, Florida, FL, USA
| | - Hemant Khanna
- Department of Ophthalmology, University of Massachusetts Medical School, Worcester, Massachusetts, MA, USA
| | - Elise Heon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Alan F. Wright
- MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, Edinburgh, Scotland, UK
| | - Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland, MD, USA
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