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Hiraoka M, Urakawa Y, Kawai K, Yoshida A, Hosakawa J, Takazawa M, Inaba A, Yokota S, Hirami Y, Takahashi M, Ohara O, Kurimoto Y, Maeda A. Copy number variant detection using next-generation sequencing in EYS-associated retinitis pigmentosa. PLoS One 2024; 19:e0305812. [PMID: 38913662 PMCID: PMC11195993 DOI: 10.1371/journal.pone.0305812] [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: 03/12/2024] [Accepted: 06/05/2024] [Indexed: 06/26/2024] Open
Abstract
Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy and a major cause of blindness. RP is caused by several variants of multiple genes, and genetic diagnosis by identifying these variants is important for optimizing treatment and estimating patient prognosis. Next-generation sequencing (NGS), which is currently widely used for diagnosis, is considered useful but is known to have limitations in detecting copy number variations (CNVs). In this study, we re-evaluated CNVs in EYS, the main causative gene of RP, identified via NGS using multiplex ligation-dependent probe amplification (MLPA). CNVs were identified in NGS samples of eight patients. To identify potential CNVs, MLPA was also performed on samples from 42 patients who were undiagnosed by NGS but carried one of the five major pathogenic variants reported in Japanese EYS-RP cases. All suspected CNVs based on NGS data in the eight patients were confirmed via MLPA. CNVs were found in 2 of the 42 NGS-undiagnosed RP cases. Furthermore, results showed that 121 of the 661 patients with RP had EYS as the causative gene, and 8.3% (10/121 patients with EYS-RP) had CNVs. Although NGS using the CNV calling criteria utilized in this study failed to identify CNVs in two cases, no false-positive results were detected. Collectively, these findings suggest that NGS is useful for CNV detection during clinical diagnosis of RP.
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Affiliation(s)
- Masakazu Hiraoka
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Yusaku Urakawa
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Kanako Kawai
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Akiko Yoshida
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Junichi Hosakawa
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Masaki Takazawa
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Akira Inaba
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
| | - Satoshi Yokota
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Yasuhiko Hirami
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Masayo Takahashi
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Vision Care Inc., Kobe, Japan
- Research Organization of Science and Technology SR Center, Ritsumeikan University, Shiga, Japan
| | - Osamu Ohara
- Department of Frontier Research and Development, Laboratory of Medical Omics Research, Kazusa DNA Research Institute, Chiba, Japan
| | - Yasuo Kurimoto
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
| | - Akiko Maeda
- Department of Ophthalmology, Kobe City Eye Hospital, Kobe, Japan
- Department of Ophthalmology, Kobe City Medical Center General Hospital, Kobe, Japan
- Research Organization of Science and Technology SR Center, Ritsumeikan University, Shiga, Japan
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2
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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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Feizabadi MH, Alerasool M, Eslahi A, Esmaeilzadeh E, Mehrjardi MYV, Saket M, Farokhi S, Fattahi Z, Khorshid HRK, Mojarrad M. Characterizing Homozygous Variants in Bardet-Biedl Syndrome-Associated Genes Within Iranian Families: Unveiling a Founder Variant in BBS2, c.471G>A. Biochem Genet 2024:10.1007/s10528-023-10637-w. [PMID: 38407766 DOI: 10.1007/s10528-023-10637-w] [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: 10/14/2023] [Accepted: 12/12/2023] [Indexed: 02/27/2024]
Abstract
Bardet-Biedl syndrome (BBS) is a rare inherited ciliopathy disorder characterized by a broad spectrum of clinical symptoms such as retinal dystrophy, obesity, polydactyly, genitourinary and kidney anomalies, learning disability, and hypogonadism. The understanding of the variants involved in BBS-causing genes remains incomplete, highlighting the need for further research to develop a molecular diagnostic strategy for this syndrome. Singleton whole-exome sequencing (WES) was performed on sixteen patients. Our study revealed (1) nine patients carried eight homozygous pathogenic variants with four of them being novel (2) Specifically, a synonymous splicing variant (c.471G > A) in BBS2 gene in six patients with Baloch ethnicity. The identification of runs of homozygosity (ROH) calling was performed using the BCFtools/RoH software on WES data of patients harboring c.471G > A variant. The presence of shared homozygous regions containing the identified variant was confirmed in these patients. In-silico analysis predicted the effect of the c.471G > A variants on BBS2 mRNA splicing. This variant results in disrupted wild-type donor site and intron retention in the mature mRNA. (3) And a deletion of exons 14 to 17 in the BBS1 gene was identified in one patient by Copy-Number Variation (CNV) analysis using the ExomeDepth pipeline. Our results identified the founder variant c.471G > A in the BBS2 gene in the Baloch ethnicity of the Iranian population. This finding can guide the diagnostic approach of this syndrome in future studies.
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Affiliation(s)
| | - Masoome Alerasool
- Genetic Foundation of Khorasan Razavi, Mashhad, Iran
- Faculty of Medicine, Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Atieh Eslahi
- Faculty of Medicine, Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | | | - Mitra Saket
- RP Eye Patients Supporting Institute, Tehran, Iran
| | - Shima Farokhi
- Faculty of Medicine, Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zohreh Fattahi
- Genetics Research Centre, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | | | - Majid Mojarrad
- Faculty of Medicine, Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, Iran.
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Liu X, Hu F, Zhang D, Li Z, He J, Zhang S, Wang Z, Zhao Y, Wu J, Liu C, Li C, Li X, Wu J. Whole genome sequencing enables new genetic diagnosis for inherited retinal diseases by identifying pathogenic variants. NPJ Genom Med 2024; 9:6. [PMID: 38245557 PMCID: PMC10799956 DOI: 10.1038/s41525-024-00391-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 12/19/2023] [Indexed: 01/22/2024] Open
Abstract
Inherited retinal diseases (IRDs) are a group of common primary retinal degenerative disorders. Conventional genetic testing strategies, such as panel-based sequencing and whole exome sequencing (WES), can only elucidate the genetic etiology in approximately 60% of IRD patients. Studies have suggested that unsolved IRD cases could be attributed to previously undetected structural variants (SVs) and intronic variants in IRD-related genes. The aim of our study was to obtain a definitive genetic diagnosis by employing whole genome sequencing (WGS) in IRD cases where the causative genes were inconclusive following an initial screening by panel sequencing. A total of 271 unresolved IRD patients and their available family members (n = 646) were screened using WGS to identify pathogenic SVs and intronic variants in 792 known ocular disease genes. Overall, 13% (34/271) of IRD patients received a confirmed genetic diagnosis, among which 7% were exclusively attributed to SVs, 4% to a combination of single nucleotide variants (SNVs) and SVs while another 2% were linked to intronic variants. 22 SVs, 3 deep-intronic variants, and 2 non-canonical splice-site variants across 14 IRD genes were identified in the entire cohort. Notably, all of these detected SVs and intronic variants were novel pathogenic variants. Among those, 74% (20/27) of variants were found in genes causally linked to Retinitis Pigmentosa (RP), with the gene EYS being the most frequently affected by SVs. The identification of SVs and intronic variants through WGS enhances the genetic diagnostic yield of IRDs and broadens the mutational spectrum of known IRD-associated genes.
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Affiliation(s)
- Xubing Liu
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Fangyuan Hu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Daowei Zhang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Zhe Li
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Jianquan He
- Computer Center, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Shenghai Zhang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Zhenguo Wang
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yingke Zhao
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Jiawen Wu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Chen Liu
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Chenchen Li
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Xin Li
- CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.
| | - Jihong Wu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China.
- NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China.
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China.
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5
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Wen S, Wang M, Qian X, Li Y, Wang K, Choi J, Pennesi ME, Yang P, Marra M, Koenekoop RK, Lopez I, Matynia A, Gorin M, Sui R, Yao F, Goetz K, Porto FBO, Chen R. Systematic assessment of the contribution of structural variants to inherited retinal diseases. Hum Mol Genet 2023; 32:2005-2015. [PMID: 36811936 PMCID: PMC10244226 DOI: 10.1093/hmg/ddad032] [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: 10/24/2022] [Revised: 01/03/2023] [Accepted: 02/11/2023] [Indexed: 02/24/2023] Open
Abstract
Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined were subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads and discordant read pairs. Polymerase Chain Reaction (PCR) followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. A total of 16 candidate pathogenic SVs were identified in 16 families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS and PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.
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Affiliation(s)
- Shu Wen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meng Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xinye Qian
- 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
| | - 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
| | - Keqing 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
| | - Jongsu Choi
- Department of Molecular and Human Genetics, 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
| | - 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
| | - Robert K Koenekoop
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, Montreal, Quebec, H4A 3S5, Canada
| | - Irma Lopez
- McGill Ocular Genetics Laboratory and Centre, Department of Paediatric Surgery, Human Genetics, and Ophthalmology, McGill University Health Centre, Montreal, Quebec, H4A 3S5, Canada
| | - Anna Matynia
- Jules Stein Eye Institute, Los Angeles, CA 90095, USA
- Ophthalmology, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Michael Gorin
- Jules Stein Eye Institute, Los Angeles, CA 90095, USA
- Ophthalmology, University of California Los Angeles David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Ruifang Sui
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100005, China
| | - Fengxia Yao
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, 100005, China
| | - Kerry Goetz
- Office of the Director, National Eye Institute/National Institutes of Health, Bethesda, MD 20892, USA
| | - Fernanda Belga Ottoni Porto
- INRET Clínica e Centro de Pesquisa, Belo Horizonte, Minas Gerais, 30150270, Brazil
- Department of Ophthalmology, Santa Casa de Misericórdia de Belo Horizonte, Belo Horizonte, Minas Gerais, 30150221, Brazil
- Centro Oftalmológico de Minas Gerais, Belo Horizonte, Minas Gerais, 30180070, Brazil
| | - 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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Han J, Joo K, Kim US, Woo SJ, Lee EK, Lee JY, Park TK, Kim SJ, Byeon SH. Voretigene Neparvovec for the Treatment of RPE65-associated Retinal Dystrophy: Consensus and Recommendations from the Korea RPE65-IRD Consensus Paper Committee. KOREAN JOURNAL OF OPHTHALMOLOGY 2023; 37:166-186. [PMID: 36950921 PMCID: PMC10151174 DOI: 10.3341/kjo.2023.0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/12/2023] [Accepted: 03/15/2023] [Indexed: 03/24/2023] Open
Abstract
Mutations in the RPE65 gene, associated with Leber congenital amaurosis, early-onset severe retinal dystrophy, and retinitis pigmentosa, gained growing attention since gene therapy for patients with RPE65-associated retinal dystrophy is available in clinical practice. RPE65 gene accounts for a very small proportion of patients with inherited retinal degeneration, especially Asian patients. Because RPE65-associated retinal dystrophy shares common clinical characteristics, such as early-onset severe nyctalopia, nystagmus, low vision, and progressive visual field constriction, with retinitis pigmentosa by other genetic mutations, appropriate genetic testing is essential to make a correct diagnosis. Also, fundus abnormalities can be minimal in early childhood, and the phenotype is highly variable depending on the type of mutations in RPE65-associated retinal dystrophy, which makes a diagnostic difficulty. The aim of this paper is to review the epidemiology of RPE65-associated retinal dystrophy, mutation spectrum, genetic diagnosis, clinical characteristics, and voretigene neparvovec, a gene therapy product for the treatment of RPE65-related retinal dystrophy.
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Affiliation(s)
- Jinu Han
- Institute of Vision Research, Department of Ophthalmology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul,
Korea
| | - Kwangsic Joo
- Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam,
Korea
| | - Ungsoo Samuel Kim
- Department of Ophthalmology, Chung-Ang University Gwangmyeong Hospital, Gwangmyeong,
Korea
| | - Se Joon Woo
- Department of Ophthalmology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam,
Korea
| | - Eun Kyoung Lee
- Department of Ophthalmology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul,
Korea
| | - Joo Yong Lee
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul,
Korea
| | - Tae Kwann Park
- Department of Ophthalmology, Soonchunhyang University Bucheon Hospital, Bucheon,
Korea
| | - Sang Jin Kim
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul,
Korea
| | - Suk Ho Byeon
- Institute of Vision Research, Department of Ophthalmology, Severance Hospital, Yonsei University College of Medicine, Seoul,
Korea
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7
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Genetic and Clinical Characterization of Danish Achromatopsia Patients. Genes (Basel) 2023; 14:genes14030690. [PMID: 36980963 PMCID: PMC10048638 DOI: 10.3390/genes14030690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/07/2023] [Accepted: 03/08/2023] [Indexed: 03/16/2023] Open
Abstract
Achromatopsia is a rare congenital condition with cone photoreceptor dysfunction causing color blindness, reduced vision, nystagmus and photophobia. New treatments are being developed, but the current evidence is still conflicting regarding possible progression over time, and there is no clear genotype-phenotype correlation. This natural history study aimed to further explore the course of disease and potential clinical differences between various genotypes. The retrospective design allowed for the study of a large cohort with a long follow-up. Patients were identified from the Danish national registries. If not already available, genetic analysis was offered to the patient. Clinical data from 1945–2022 were retrieved from medical records and included best-corrected visual acuity (BCVA), color vision, refractive error, nystagmus, visual fields and fundoscopic findings. We identified variants believed to be disease causing in five of the known achromatopsia genes: CNGA3; CNGB3; GNAT2; PDE6C and PDE6H; and novel variants were identified in CNGB3 and PDE6C. Progressive deterioration of BCVA only attributable to achromatopsia was found in three of 58 patients. Progressive phenotype was seen with variants in CNGB3 and PDE6C. The results indicate that myopia could be more frequently occurring with variants in GNAT2, PDE6C and PDE6H and support the evidence that achromatopsia is a predominantly stationary condition with respect to BCVA. Although a clear genotype-phenotype correlation can still not be concluded, there may be differences in phenotypical characteristics with variants in different genes.
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8
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Wen S, Wang M, Qian X, Li Y, Wang K, Choi J, Pennesi ME, Yang P, Marra M, Koenekoop RK, Lopez I, Matynia A, Gorin M, Sui R, Yao F, Goetz K, Porto FBO, Chen R. Systematic assessment of the contribution of structural variants to inherited retinal diseases. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.02.522522. [PMID: 36789417 PMCID: PMC9928032 DOI: 10.1101/2023.01.02.522522] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined was subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY, and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these four algorithms were included for further analysis. AnnotSV was used to annotate these SVs. SVs that overlap with known IRD-associated genes were examined with sequencing coverage, junction reads, and discordant read pairs. PCR followed by Sanger sequencing was used to further confirm the SVs and identify the breakpoints. Segregation of the candidate pathogenic alleles with the disease was performed when possible. In total, sixteen candidate pathogenic SVs were identified in sixteen families, including deletions and inversions, representing 2.1% of patients with previously unsolved IRDs. Autosomal dominant, autosomal recessive, and X-linked inheritance of disease-causing SVs were observed in 12 different genes. Among these, SVs in CLN3, EYS, PRPF31 were found in multiple families. Our study suggests that the contribution of SVs detected by short-read WGS is about 0.25% of our IRD patient cohort and is significantly lower than that of single nucleotide changes and small insertions and deletions.
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9
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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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10
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Mustafi D, Bharathan SP, Calderon R, Nagiel A. HUMAN CELLULAR MODELS FOR RETINAL DISEASE: From Induced Pluripotent Stem Cells to Organoids. Retina 2022; 42:1829-1835. [PMID: 35858274 PMCID: PMC10119785 DOI: 10.1097/iae.0000000000003571] [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: 03/14/2022] [Accepted: 07/10/2022] [Indexed: 11/25/2022]
Abstract
PURPOSE To provide a concise review of induced pluripotent stem cells (iPSCs) and retinal organoids as models for human retinal diseases and their role in gene discovery and treatment of inherited retinal diseases (IRDs). METHODS A PubMed literature review was performed for models of human retinal disease, including animal models and human pluripotent stem cell-derived models. RESULTS There is a growing body of research on retinal disease using human pluripotent stem cells. This is a significant change from just a decade ago when most research was performed on animal models. The advent of induced pluripotent stem cells has permitted not only the generation of two-dimensional human cell cultures such as RPE but also more recently the generation of three-dimensional retinal organoids that better reflect the multicellular laminar architecture of the human retina. CONCLUSION Modern stem cell techniques are improving our ability to model human retinal disease in vitro, especially with the use of patient-derived induced pluripotent stem cells. In the future, a personalized approach may be used in which the individual's unique genotype can be modeled in two-dimensional culture or three-dimensional organoids and then rescued with an optimized therapy before treating the patient.
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Affiliation(s)
- Debarshi Mustafi
- Department of Ophthalmology, Karalis Johnson Retina Center, University of Washington, Seattle, Washington
- Department of Ophthalmology, Seattle Children's Hospital, Seattle, Washington
- Brotman Baty Institute for Precision Medicine, Seattle, Washington
| | - Sumitha P Bharathan
- The Vision Center, Department of Surgery, Children's Hospital Los Angeles, Los Angeles, California
- The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Rosanna Calderon
- The Vision Center, Department of Surgery, Children's Hospital Los Angeles, Los Angeles, California
- The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
- Department of Development, Stem Cells and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California; and
| | - Aaron Nagiel
- The Vision Center, Department of Surgery, Children's Hospital Los Angeles, Los Angeles, California
- The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
- Department of Ophthalmology, Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, California
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11
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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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12
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Nasser F, Kohl S, Kurtenbach A, Kempf M, Biskup S, Zuleger T, Haack TB, Weisschuh N, Stingl K, Zrenner E. Ophthalmic and Genetic Features of Bardet Biedl Syndrome in a German Cohort. Genes (Basel) 2022; 13:genes13071218. [PMID: 35886001 PMCID: PMC9322102 DOI: 10.3390/genes13071218] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 06/29/2022] [Accepted: 07/02/2022] [Indexed: 12/04/2022] Open
Abstract
The aim of this study was to characterize the ophthalmic and genetic features of Bardet Biedl (BBS) syndrome in a cohort of patients from a German specialized ophthalmic care center. Sixty-one patients, aged 5−56 years, underwent a detailed ophthalmic examination including visual acuity and color vision testing, electroretinography (ERG), visually evoked potential recording (VEP), fundus examination, and spectral domain optical coherence tomography (SD-OCT). Adaptive optics flood illumination ophthalmoscopy was performed in five patients. All patients had received diagnostic genetic testing and were selected upon the presence of apparent biallelic variants in known BBS-associated genes. All patients had retinal dystrophy with morphologic changes of the retina. Visual acuity decreased from ~0.2 (decimal) at age 5 to blindness 0 at 50 years. Visual field examination could be performed in only half of the patients and showed a concentric constriction with remaining islands of function in the periphery. ERG recordings were mostly extinguished whereas VEP recordings were reduced in about half of the patients. The cohort of patients showed 51 different likely biallelic mutations—of which 11 are novel—in 12 different BBS-associated genes. The most common associated genes were BBS10 (32.8%) and BBS1 (24.6%), and by far the most commonly observed variants were BBS10 c.271dup;p.C91Lfs*5 (21 alleles) and BBS1 c.1169T>G;p.M390R (18 alleles). The phenotype associated with the different BBS-associated genes and genotypes in our cohort is heterogeneous, with diverse features without genotype−phenotype correlation. The results confirm and expand our knowledge of this rare disease.
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Affiliation(s)
- Fadi Nasser
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
- Department of Ophthalmology, University of Leipzig, 04103 Leipzig, Germany
- Correspondence:
| | - Susanne Kohl
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
| | - Anne Kurtenbach
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
| | - Melanie Kempf
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tuebingen, Germany
| | | | - Theresia Zuleger
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tuebingen, Germany; (T.Z.); (T.B.H.)
| | - Tobias B. Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tuebingen, Germany; (T.Z.); (T.B.H.)
| | - Nicole Weisschuh
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
| | - Katarina Stingl
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
- Center for Rare Eye Diseases, University of Tübingen, 72076 Tuebingen, Germany
| | - Eberhart Zrenner
- Centre for Ophthalmology, University of Tübingen, 72076 Tuebingen, Germany; (S.K.); (A.K.); (M.K.); (N.W.); (K.S.); (E.Z.)
- Werner Reichardt Centre for Integrative Neuroscience (CIN), University of Tübingen, 72076 Tuebingen, Germany
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13
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Mustafi D, Hisama FM, Huey J, Chao JR. The current state of genetic testing platforms for inherited retinal diseases. Ophthalmol Retina 2022; 6:702-710. [PMID: 35307606 PMCID: PMC9356993 DOI: 10.1016/j.oret.2022.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/08/2022] [Accepted: 03/14/2022] [Indexed: 11/30/2022]
Abstract
PURPOSE To evaluate genetic testing platforms used to aid in the diagnosis of inherited retinal degenerations (IRDs). DESIGN Evaluation of diagnostic test or technology SUBJECTS: Targeted genetic panel testing for IRDs METHODS, INTERVENTION, OR TESTING: Data collected regarding targeted genetic panel testing for IRDs offered by different labs were investigated for inclusion of coding and non-coding variants in disease genes. Both large IRD panels and smaller, more focused disease specific panels were included in the analysis. MAIN OUTCOME MEASURES Number of disease genes tested as well as the commonality and uniqueness across testing platforms in both coding and non-coding variants of disease. RESULTS Across the three IRD panel tests investigated, 409 unique genes are represented, of which 269 genes are tested by all three panels. The top 20 genes known to cause over 70% of all IRDs are represented in the 269 common genes tested by all three panels. In addition, 138 non-coding variants are assayed across the three platforms in 50 unique genes. Focused disease specific panels exhibited significant variability across 5 testing platforms that were studied. CONCLUSIONS Ordering genetic testing for IRDs is not straightforward, as evidenced by the multitude of panels available to providers. It is important that there is coverage of both coding and non-coding regions in IRD genes to offer a diagnosis in these patients. This paper details the diversity of testing platforms currently available to clinicians and provides a thorough explanation of genes tested in the different IRD panels. In a time of increased importance for clinical genetic testing of IRD patients, knowledge of the proper test to order is paramount.
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Affiliation(s)
- Debarshi Mustafi
- Department of Ophthalmology, University of Washington, Seattle, Washington; Department of Ophthalmology, Seattle Children's Hospital, Seattle, Washington.
| | - Fuki M Hisama
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, Washington
| | - Jennifer Huey
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington
| | - Jennifer R Chao
- Department of Ophthalmology, University of Washington, Seattle, Washington
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14
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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: 45] [Impact Index Per Article: 15.0] [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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15
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Aoun M, Passerini I, Chiurazzi P, Karali M, De Rienzo I, Sartor G, Murro V, Filimonova N, Seri M, Banfi S. Inherited Retinal Diseases Due to RPE65 Variants: From Genetic Diagnostic Management to Therapy. Int J Mol Sci 2021; 22:7207. [PMID: 34281261 PMCID: PMC8268668 DOI: 10.3390/ijms22137207] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/25/2021] [Accepted: 06/29/2021] [Indexed: 12/18/2022] Open
Abstract
Inherited retinal diseases (IRDs) are a heterogeneous group of conditions that include retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA) and early-onset severe retinal dystrophy (EO[S]RD), which differ in severity and age of onset. IRDs are caused by mutations in >250 genes. Variants in the RPE65 gene account for 0.6-6% of RP and 3-16% of LCA/EORD cases. Voretigene neparvovec is a gene therapy approved for the treatment of patients with an autosomal recessive retinal dystrophy due to confirmed biallelic RPE65 variants (RPE65-IRDs). Therefore, the accurate molecular diagnosis of RPE65-IRDs is crucial to identify 'actionable' genotypes-i.e., genotypes that may benefit from the treatment-and is an integral part of patient management. To date, hundreds of RPE65 variants have been identified, some of which are classified as pathogenic or likely pathogenic, while the significance of others is yet to be established. In this review, we provide an overview of the genetic diagnostic workup needed to select patients that could be eligible for voretigene neparvovec treatment. Careful clinical characterization of patients by multidisciplinary teams of experts, combined with the availability of next-generation sequencing approaches, can accelerate patients' access to available therapeutic options.
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Affiliation(s)
- Manar Aoun
- Novartis Farma, Largo Boccioni 1, 21040 Origgio, Italy;
| | - Ilaria Passerini
- Department of Genetic Diagnosis, Careggi Teaching Hospital, 50134 Florence, Italy;
| | - Pietro Chiurazzi
- Istituto di Medicina Genomica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy;
- Fondazione Policlinico Universitario “A. Gemelli” IRCCS, UOC Genetica Medica, 00168 Roma, Italy
| | - Marianthi Karali
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, 80131 Naples, Italy;
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Irene De Rienzo
- Department of Ophthalmology, AOU-Careggi, 50234 Florence, Italy;
| | - Giovanna Sartor
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
| | - Vittoria Murro
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Eye Clinic Careggi Teaching Hospital, 50234 Florence, Italy;
| | | | - Marco Seri
- Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy;
- Department of Surgical and Medical Sciences, University of Bologna, 40138 Bologna, Italy
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
- Medical Genetics, Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
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PHENOTYPE-GUIDED GENETIC TESTING OF PEDIATRIC INHERITED RETINAL DISEASE IN THE UNITED ARAB EMIRATES. Retina 2021; 40:1829-1837. [PMID: 31725702 DOI: 10.1097/iae.0000000000002675] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Inherited retinal disease is relatively common in the Arabian Gulf, but details regarding pediatric inherited retinal disease in the region are lacking. The purpose of this study is to report the experience of a regional Ocular Genetics Service with childhood-onset inherited retinal disease in the United Arab Emirates. METHODS Retrospective series of consecutive Emirati patients referred to the Ocular Genetics Service of Cleveland Clinic Abu Dhabi over a 3-year period (2016-2018) who were diagnosed with childhood-onset inherited retinal disease (onset before 16 years old) and underwent diagnostic genetic testing guided by clinical phenotype (single gene, next-generation panel, or exome sequencing). RESULTS Seventy-one probands were identified (38 male and 33 females), the majority of whom were symptomatic with visual problems within the first 5 years of life. All patients had disease causing mutations in 1 of 26 retinal disease genes. Recessive disease was frequently due to homozygous mutations. The most frequently mutated genes (and number of probands) were ABCA4 (14), KCNV2 (8), CRB1 (6), and CNGA3 (5). Recurrent specific gene mutations included ABCA4 p.Gly1961Glu/p.Leu857Pro, KCNV2 p.Glu143*, MERTK p.Cys738Trpfs*32, and RS1 c.52+3A>G. Some probands had mutations in syndromic genes and were confirmed to have extraocular findings. CONCLUSION Phenotype-guided genetic testing had a remarkable yield for this patient population. Recessive disease is often from homozygous mutations. Cone-dominated phenotypes are common. There are apparent founder mutations for several genes that could be used in a targeted genetic testing strategy. Molecular diagnosis is particularly important in affected children when inherited retinal dystrophy could be a sign of syndromic disease as proper earlier diagnosis minimizes potential extraocular morbidity.
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Nassisi M, Smirnov VM, Solis Hernandez C, Mohand‐Saïd S, Condroyer C, Antonio A, Kühlewein L, Kempf M, Kohl S, Wissinger B, Nasser F, Ragi SD, Wang N, Sparrow JR, Greenstein VC, Michalakis S, Mahroo OA, Ba‐Abbad R, Michaelides M, Webster AR, Degli Esposti S, Saffren B, Capasso J, Levin A, Hauswirth WW, Dhaenens C, Defoort‐Dhellemmes S, Tsang SH, Zrenner E, Sahel J, Petersen‐Jones SM, Zeitz C, Audo I. CNGB1-related rod-cone dystrophy: A mutation review and update. Hum Mutat 2021; 42:641-666. [PMID: 33847019 PMCID: PMC8218941 DOI: 10.1002/humu.24205] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/26/2021] [Accepted: 04/08/2021] [Indexed: 12/29/2022]
Abstract
Cyclic nucleotide-gated channel β1 (CNGB1) encodes the 240-kDa β subunit of the rod photoreceptor cyclic nucleotide-gated ion channel. Disease-causing sequence variants in CNGB1 lead to autosomal recessive rod-cone dystrophy/retinitis pigmentosa (RP). We herein present a comprehensive review and analysis of all previously reported CNGB1 sequence variants, and add 22 novel variants, thereby enlarging the spectrum to 84 variants in total, including 24 missense variants (two of which may also affect splicing), 21 nonsense, 19 splicing defects (7 at noncanonical positions), 10 small deletions, 1 small insertion, 1 small insertion-deletion, 7 small duplications, and 1 gross deletion. According to the American College of Medical Genetics and Genomics classification criteria, 59 variants were considered pathogenic or likely pathogenic and 25 were variants of uncertain significance. In addition, we provide further phenotypic data from 34 CNGB1-related RP cases, which, overall, are in line with previous findings suggesting that this form of RP has long-term retention of useful central vision despite the early onset of night blindness, which is valuable for patient counseling, but also has implications for it being considered a priority target for gene therapy trials.
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Affiliation(s)
- Marco Nassisi
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
- Centre Hospitalier National d'Ophtalmologie des Quinze‐Vingts, INSERM‐DGOS CIC1423ParisFrance
- Department of Clinical Sciences and Community HealthUniversity of MilanMilanItaly
- Ophthalmological Unit, Fondazione IRCCS Ca' GrandaOspedale Maggiore PoliclinicoMilanItaly
| | - Vasily M. Smirnov
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
- Exploration de la vision et Neuro‐Ophthalmologie, CHU de LilleLilleFrance
- Faculté de MédecineUniversité de LilleLilleFrance
| | - Cyntia Solis Hernandez
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
| | - Saddek Mohand‐Saïd
- Centre Hospitalier National d'Ophtalmologie des Quinze‐Vingts, INSERM‐DGOS CIC1423ParisFrance
| | - Christel Condroyer
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
| | - Aline Antonio
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
| | - Laura Kühlewein
- University Eye Hospital, Centre for OphthalmologyUniversity of TübingenTübingenGermany
- Institute for Ophthalmic Research, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Melanie Kempf
- University Eye Hospital, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Fadi Nasser
- University Eye Hospital, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Sara D. Ragi
- Department of OphthalmologyColumbia University, New YorkNew YorkUSA
| | - Nan‐Kai Wang
- Department of OphthalmologyColumbia University, New YorkNew YorkUSA
- College of MedicineChang Gung UniversityTaoyuanTaiwan
- Department of Ophthalmology, Chang Gung Memorial HospitalLinkou Medical CenterTaoyuanTaiwan
| | - Janet R. Sparrow
- Department of OphthalmologyColumbia University, New YorkNew YorkUSA
| | | | | | - Omar A. Mahroo
- Moorfields Eye HospitalLondonUK
- UCL Institute of Ophthalmology, University College LondonLondonUK
| | - Rola Ba‐Abbad
- Moorfields Eye HospitalLondonUK
- UCL Institute of Ophthalmology, University College LondonLondonUK
| | - Michel Michaelides
- Moorfields Eye HospitalLondonUK
- UCL Institute of Ophthalmology, University College LondonLondonUK
| | - Andrew R. Webster
- Moorfields Eye HospitalLondonUK
- UCL Institute of Ophthalmology, University College LondonLondonUK
| | - Simona Degli Esposti
- Moorfields Eye HospitalLondonUK
- UCL Institute of Ophthalmology, University College LondonLondonUK
| | - Brooke Saffren
- Philadelphia College of Osteopathic MedicinePhiladelphiaPennsylvaniaUSA
| | | | - Alex Levin
- Pediatric Ophthalmology and Ocular Genetics, Flaum Eye Institute, Pediatric Genetics, Golisano Children's HospitalUniversity of RochesterRochesterNew YorkUSA
| | | | - Claire‐Marie Dhaenens
- Univ. Lille, Inserm, CHU Lille, U1172‐LilNCog‐Lille Neuroscience & CognitionLilleFrance
| | | | - Stephen H. Tsang
- Department of OphthalmologyColumbia University, New YorkNew YorkUSA
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma LaboratoryNew YorkNew YorkUSA
- Department of Pathology and Cell BiologyColumbia UniversityNew YorkNew YorkUSA
- Stem Cell Initiative (CSCI), Institute of Human Nutrition, Vagelos College of Physicians and SurgeonsNew YorkNew YorkUSA
| | - Eberhart Zrenner
- University Eye Hospital, Centre for OphthalmologyUniversity of TübingenTübingenGermany
| | - Jose‐Alain Sahel
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
- Department of OphthalmologyThe University of Pittsburgh School of MedicinePittsburghPennsylvaniaUSA
- Fondation Ophtalmologique Adolphe de RothschildParisFrance
| | - Simon M. Petersen‐Jones
- Department of Small Animal Clinical SciencesMichigan State UniversityEast LansingMichiganUSA
| | - Christina Zeitz
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
| | - Isabelle Audo
- Sorbonne Université, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche ScientifiqueInstitut de la VisionParisFrance
- Centre Hospitalier National d'Ophtalmologie des Quinze‐Vingts, INSERM‐DGOS CIC1423ParisFrance
- University College London Institute of OphthalmologyLondonUK
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18
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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: 26] [Impact Index Per Article: 8.7] [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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19
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Daich Varela M, Ullah E, Yousaf S, Brooks BP, Hufnagel RB, Huryn LA. PDE6C: Novel Mutations, Atypical Phenotype, and Differences Among Children and Adults. Invest Ophthalmol Vis Sci 2021; 61:1. [PMID: 33001157 PMCID: PMC7545085 DOI: 10.1167/iovs.61.12.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Purpose Genetic variation in PDE6C is associated with achromatopsia and cone dystrophy, with only a few reports of cone-rod dystrophy in the literature. We describe two pediatric and two adult patients with PDE6C related cone and cone-rod dystrophy and the first longitudinal data of a pediatric patient with PDE6C-related cone dystrophy. Methods This cohort of four patients underwent comprehensive ophthalmologic evaluation at the National Eye Institute's Ophthalmic Genetics clinic, including visual field testing, retinal imaging and electroretinogram (ERG). Next-generation sequencing-based genetic testing was performed and subsequent analysis of the variants was done through three-dimensional protein models generated by Phyre2 and Chimera. Results All cases shared decreased best-corrected visual acuity and poor color discrimination. Three of the four patients had a cone-rod dystrophy, presenting with an ERG showing decreased amplitude on both photopic and scotopic waveforms and a mild to moderately constricted visual field. One of the children was diagnosed with cone dystrophy, having a preserved peripheral field. The children had none to minor structural retinal changes, whereas the adults had clear macular dystrophy. Conclusions PDE6C-related cone-rod dystrophy consists of a severe phenotype characterized by early-onset nystagmus, decreased best-corrected visual acuity, poor color discrimination, progressive constriction of the visual field, and night blindness. Our work contributes with valuable information toward understanding the visual prognosis and allelic heterogeneity of PDE6C-related cone and cone-rod dystrophy.
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Affiliation(s)
- Malena Daich Varela
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Ehsan Ullah
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Sairah Yousaf
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Brian P Brooks
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Robert B Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Laryssa A Huryn
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
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20
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Bettini S, Bombonato G, Dassie F, Favaretto F, Piffer L, Bizzotto P, Busetto L, Chemello L, Senzolo M, Merkel C, Angeli P, Vettor R, Milan G, Maffei P. Liver Fibrosis and Steatosis in Alström Syndrome: A Genetic Model for Metabolic Syndrome. Diagnostics (Basel) 2021; 11:diagnostics11050797. [PMID: 33924909 PMCID: PMC8170882 DOI: 10.3390/diagnostics11050797] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/18/2021] [Accepted: 04/24/2021] [Indexed: 12/27/2022] Open
Abstract
Alström syndrome (ALMS) is an ultra-rare monogenic disease characterized by insulin resistance, multi-organ fibrosis, obesity, type 2 diabetes mellitus (T2DM), and hypertriglyceridemia with high and early incidence of non-alcoholic fatty liver disease (NAFLD). We evaluated liver fibrosis quantifying liver stiffness (LS) by shear wave elastography (SWE) and steatosis using ultrasound sonographic (US) liver/kidney ratios (L/K) in 18 patients with ALMS and 25 controls, and analyzed the contribution of metabolic and genetic alterations in NAFLD progression. We also genetically characterized patients. LS and L/K values were significantly higher in patients compared with in controls (p < 0.001 versus p = 0.013). In patients, LS correlated with the Fibrosis-4 Index and age, while L/K was associated with triglyceride levels. LS showed an increasing trend in patients with metabolic comorbidities and displayed a significant correlation with waist circumference, the homeostasis model assessment, and glycated hemoglobin A1c. SWE and US represent promising tools to accurately evaluate early liver fibrosis and steatosis in adults and children with ALMS during follow-up. We described a new pathogenic variant of exon 8 in ALMS1. Patients with ALMS displayed enhanced steatosis, an early increased age-dependent LS that is associated with obesity and T2DM but also linked to genetic alterations, suggesting that ALMS1 could be involved in liver fibrogenesis.
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Affiliation(s)
- Silvia Bettini
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
- Correspondence: (S.B.); (F.D.); Tel.: +39-333-204-6896 (S.B.); Tel.: +39-049-821-7021 (F.D.)
| | - Giancarlo Bombonato
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Francesca Dassie
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
- Correspondence: (S.B.); (F.D.); Tel.: +39-333-204-6896 (S.B.); Tel.: +39-049-821-7021 (F.D.)
| | - Francesca Favaretto
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
| | - Luca Piffer
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Paola Bizzotto
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Luca Busetto
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
| | - Liliana Chemello
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Marco Senzolo
- Gastroenterology Department of Oncological and Gastroenterological Surgical Sciences, DiSCOG, University of Padua, 35128 Padua, Italy;
| | - Carlo Merkel
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Paolo Angeli
- Internal Medicine 5, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (G.B.); (L.P.); (P.B.); (L.C.); (C.M.); (P.A.)
| | - Roberto Vettor
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
| | - Gabriella Milan
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
| | - Pietro Maffei
- Internal Medicine 3, Department of Medicine, DIMED, University of Padua, 35128 Padua, Italy; (F.F.); (L.B.); (R.V.); (G.M.); (P.M.)
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21
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Kohl S, Llavona P, Sauer A, Reuter P, Weisschuh N, Kempf M, Dehmelt FA, Arrenberg AB, Sliesoraityte I, Zrenner E, van Schooneveld MJ, Rudolph G, Kühlewein L, Wissinger B. A duplication on chromosome 16q12 affecting the IRXB gene cluster is associated with autosomal dominant cone dystrophy with early tritanopic color vision defect. Hum Mol Genet 2021; 30:1218-1229. [PMID: 33891002 PMCID: PMC8212766 DOI: 10.1093/hmg/ddab117] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/15/2021] [Accepted: 04/15/2021] [Indexed: 02/06/2023] Open
Abstract
Cone dystrophies are a rare subgroup of inherited retinal dystrophies and hallmarked by color vision defects, low or decreasing visual acuity and central vision loss, nystagmus and photophobia. Applying genome-wide linkage analysis and array comparative genome hybridization, we identified a locus for autosomal dominant cone dystrophy on chromosome 16q12 in four independent multigeneration families. The locus is defined by duplications of variable size with a smallest region of overlap of 608 kb affecting the IRXB gene cluster and encompasses the genes IRX5 and IRX6. IRX5 and IRX6 belong to the Iroquois (Iro) protein family of homeodomain-containing transcription factors involved in patterning and regionalization of embryonic tissue in vertebrates, including the eye and the retina. All patients presented with a unique progressive cone dystrophy phenotype hallmarked by early tritanopic color vision defects. We propose that the disease underlies a misregulation of the IRXB gene cluster on chromosome 16q12 and demonstrate that overexpression of Irx5a and Irx6a, the two orthologous genes in zebrafish, results in visual impairment in 5-day-old zebrafish larvae.
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Affiliation(s)
- Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Pablo Llavona
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Alexandra Sauer
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Peggy Reuter
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Nicole Weisschuh
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Melanie Kempf
- University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Universitätsklinikum Tübingen, Tübingen 72076, Germany.,Center for Rare Eye Diseases, University of Tübingen, Tübingen 72076, Germany
| | - Florian Alexander Dehmelt
- Werner Reichardt Centre for Integrative Neuroscience and Institute of Neurobiology, University of Tübingen, Tübingen 72076, Germany
| | - Aristides B Arrenberg
- Werner Reichardt Centre for Integrative Neuroscience and Institute of Neurobiology, University of Tübingen, Tübingen 72076, Germany
| | - Ieva Sliesoraityte
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
| | - Eberhart Zrenner
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany.,Werner Reichardt Centre for Integrative Neuroscience and Institute of Neurobiology, University of Tübingen, Tübingen 72076, Germany
| | - Mary J van Schooneveld
- Department of Ophthalmology, Amsterdam University Medical Centre, Amsterdam 1100 DD, The Netherlands.,Bartiméus Diagnostic Department, Zeist, The Netherlands
| | - Günther Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, München 80336, Germany
| | - Laura Kühlewein
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany.,University Eye Hospital, Centre for Ophthalmology, University of Tübingen, Universitätsklinikum Tübingen, Tübingen 72076, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen 72076, Germany
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22
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Genetic characteristics and epidemiology of inherited retinal degeneration in Taiwan. NPJ Genom Med 2021; 6:16. [PMID: 33608557 PMCID: PMC7896090 DOI: 10.1038/s41525-021-00180-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/12/2021] [Indexed: 01/08/2023] Open
Abstract
Inherited retinal degenerations (IRDs) are a group of phenotypically and genotypically heterogeneous disorders with substantial socioeconomic impact. In this cohort study, we tried to address the genetic characteristics and epidemiology of IRDs in Taiwan. Totally, 312 families with IRDs were identified and recruited and genetic testing was performed via probe capture-based NGS targeting 212 IRD-related genes. Statistical analysis was based on the proband of each affected family. Disease-causing genotypes were identified in 178 families (57.1%). ABCA4 variants were the most common cause of disease in this cohort (27 families, 15.2%), whereas CYP4V2 variants were the most common cause for the single phenotype—Bietti’s crystalline dystrophy (12 families, 3.8%). Some variants such as ABCA4:c.1804C>T, CYP4V2:c.802-8_810delinsGC, and EYS:c6416G>A were population-specific disease-causing hotspots. Probands affected by ABCA4, RPGR, RP1L1, and CEP290 sought medical help earlier while patients affected by EYS and CYP4V2 visited our clinic at an older age. To evaluate the representativeness of our cohort in the genetic epidemiology of IRDs in Taiwan, our demographic data were compared with that of the total IRD population in Taiwan, obtained from the National Health Insurance Research Database. This is currently the largest-scale, comprehensive study investigating the genetic characteristics and epidemiology of IRD in Taiwan. These data could help patients and caregivers to adopt precision genomic medicine and novel gene therapies in near future.
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23
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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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24
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Dassie F, Lorusso R, Benavides-Varela S, Milan G, Favaretto F, Callus E, Cagnin S, Reggiani F, Minervini G, Tosatto S, Vettor R, Semenza C, Maffei P. Neurocognitive assessment and DNA sequencing expand the phenotype and genotype spectrum of Alström syndrome. Am J Med Genet A 2021; 185:732-742. [PMID: 33410256 DOI: 10.1002/ajmg.a.62029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 11/04/2020] [Accepted: 11/11/2020] [Indexed: 12/25/2022]
Abstract
Alström syndrome (OMIM#203800) is an ultra-rare autosomal recessive monogenic disease presenting pathogenic variants in ALMS1 (chromosome 2p13). It is characterized by early onset of blindness, hearing loss and systemic comorbidities, with delayed development without cognitive impairment. We aimed to investigate the cognitive functions and describe new pathogenic variants in Alström syndrome patients. Nineteen patients (13 adults, 6 children) underwent a thorough clinical, genetic, laboratory, instrumental, and neurocognitive assessment. Six new pathogenic variants in ALMS1 including the first described in exon 6 were identified. Four patients displayed a "mild phenotype" characterized by slow disease onset or absence of complications, including childhood obesity and association with at least one pathogenic variant in exon 5 or 6. At neurocognitive testing, a significant proportion of patients had deficits in three neurocognitive domains: similarities, phonological memory, and apraxia. In particular, 53% of patients showed difficulties in the auditory working memory test. We found ideomotor and buccofacial apraxia in 74% of patients. "Mild phenotype" patients performed better on auditory working memory and ideomotor apraxia test than "typical phenotype" ones (91.9 + 16.3% vs. 41.7 + 34.5% of correct answers, Z = 64.5, p < .01 and 92.5 + 9.6 vs. 61.7 + 26.3, Z = 61, p < .05, respectively). Deficits in auditory working memory, ideomotor, and buccofacial apraxia were found in these patients and fewer neuropsychological deficits were found in the "mild" phenotype group. Furthermore, in the "mild" phenotype group, it was found that all pathogenic variants are localized before exon 8.
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Affiliation(s)
| | | | | | | | | | - Edward Callus
- Clinical Psychology Service, IRCCS Policlinico San Donato, Milan, Italy.,Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | - Stefano Cagnin
- DiBio, Università di Padova, Padova, Italy.,CRIBI Biotechnology Center, Università di Padova, Padova, Italy
| | | | | | - Silvio Tosatto
- DSB, Università di Padova, Padova, Italy.,CNR Institute of Neuroscience, Padova, Italy
| | | | - Carlo Semenza
- DNS (PNC), Università di Padova, Padova, Italy.,IRCCS Ospedale S Camillo, Venezia, Italy
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25
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Genetic and Clinical Findings in an Ethnically Diverse Cohort with Retinitis Pigmentosa Associated with Pathogenic Variants in CERKL. Genes (Basel) 2020; 11:genes11121497. [PMID: 33322828 PMCID: PMC7763961 DOI: 10.3390/genes11121497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 01/06/2023] Open
Abstract
Autosomal recessive retinitis pigmentosa is caused by mutations in over 40 genes, one of which is the ceramide kinase-like gene (CERKL). We present a case series of six patients from six unrelated families diagnosed with inherited retinal dystrophies (IRD) and with two variants in CERKL recruited from a multi-ethnic British population. A retrospective review of clinical data in these patients was performed and included colour fundus photography, fundus autofluorescence (AF) imaging, spectral domain–optical coherence tomography (SD–OCT), visual fields and electroretinogram (ERG) assessment where available. Three female and three male patients were included. Age at onset ranged from 7 years old to 45 years, with three presenting in their 20s and two presenting in their 40s. All but one had central visual loss as one of their main presenting symptoms. Four patients had features of retinitis pigmentosa with significant variation in severity and extent of disease, and two patients had no pigment deposition with only macular involvement clinically. Seven variants in CERKL were identified, of which three are novel. The inherited retinopathies associated with the CERKL gene vary in age at presentation and in degree of severity, but generally are characterised by a central visual impairment early on.
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26
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Sun W, Li S, Xiao X, Wang P, Zhang Q. Genotypes and phenotypes of genes associated with achromatopsia: A reference for clinical genetic testing. Mol Vis 2020; 26:588-602. [PMID: 32913385 PMCID: PMC7479066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 08/20/2020] [Indexed: 11/23/2022] Open
Abstract
PURPOSE Achromatopsia is a congenital autosomal recessive cone disorder, and it has been found to be associated with six genes. However, pathogenic variants in these six genes have been identified in patients with various retinal dystrophies with the exception of achromatopsia. Thus, this study aims to investigate the contribution of these genes in hereditary retinal diseases and the potential genotype-phenotype correlations. METHODS Biallelic variants in six achromatopsia-related genes, namely, CNGA3, CNGB3, GNAT2, ATF6, PDE6C, and PDE6H, were analyzed based on data obtained from 7,195 probands with different eye conditions. A systematic genotype-phenotype analysis of these genes was performed based on these data, along with the data reported in the literature. RESULTS Biallelic potential pathogenic variants (PPVs) in five of the six genes were identified in 119 probands with genetic eye diseases. The variants in CNGA3 were the most common and accounted for 81.5% (97/119). Of the 119 probands, 62.2% (74/119) have cone-rod dystrophy, whereas only 25.2% (30/119) have achromatopsia. No biallelic pathogenic variants in these genes were identified in patients with rod-dominant degeneration. A systematic review of genotypes and phenotypes revealed certain characteristics of each of the six genes, providing clues for the pathogenicity evaluation of the variants of the genes. CONCLUSIONS PPVs in the six genes were identified in various inherited retinal degeneration diseases, most of which are cone-dominant diseases but no rod-dominant diseases based on the data from a cohort of 7,195 probands with different eye conditions. The systematic genotype-phenotype analysis of these genes will be useful in drafting guidelines for the clinical genetic diagnostic application for the investigated genes.
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Yuan S, Qi R, Fang X, Wang X, Zhou L, Sheng X. Two novel PDE6C gene mutations in Chinese family with achromatopsia. Ophthalmic Genet 2020; 41:591-598. [PMID: 32787476 DOI: 10.1080/13816810.2020.1802762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Background: Achromatopsia (ACHM) is an inherited retinal disease affecting the cone cell function. To date, six pathogenic genes of ACHM have been identified. However, the diagnostic and therapeutic methods of this disorder remain limited. Herein, to characterize the clinical features and genetic causes of three affected siblings in a Chinese family with ACHM, we used target next-generation sequencing (NGS) and found new pathogenic factors associated with ACHM in this family. Materials and methods: Three patients with ACHM and three healthy family members were included in this study. All participants received comprehensive ophthalmic tests. NGS approach was performed on the patients to determine the causative mutation for this family. The silico analysis was also applied to predict the pathogenesis of identified mutations. Results: Genetic assessments revealed compound heterozygous mutations of the PDE6C gene (c.1413 + 1 G > C, c.305 G > A), carried by all three patients. Both mutations were novel and predicted to be deleterious by six types of online predictive software. The heterozygous PDE6C missense mutation (c.305 G > A) was found from the mother and the heterozygous PDE6C splice site mutation (c.1413 + 1 G > C) was found in the father and all the children. All patients in the family showed typical signs and symptoms of ACHM. Conclusions: We report novel compound heterozygous PDE6C mutations in causing ACHM and further confirm the clinical diagnosis. Our study extends the genotypic spectrums for PDE6C-ACHM and better illustrates its genotype-phenotype correlations, which would help the ACHM patients with better genetic diagnosis, prognosis, and gene treatment.
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Affiliation(s)
- Shiqin Yuan
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China
| | - Rui Qi
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China.,Aier Eye Hospital Group, Hubin Aier Eye Hospital , Binzhou, Shangdong, China
| | - Xinhe Fang
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China
| | - Xiaoguang Wang
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China
| | - Liang Zhou
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China
| | - Xunlun Sheng
- Ningxia Clinical Research Center of Blinding Eye Disease, Ningxia Eye Hospital, People Hospital of Ningxia Hui Autonomous Region (First Affiliated Hospital of Northwest University for Nationalities) , Yinchuan, China
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Di Scipio M, Tavares E, Deshmukh S, Audo I, Green-Sanderson K, Zubak Y, Zine-Eddine F, Pearson A, Vig A, Tang CY, Mollica A, Karas J, Tumber A, Yu CW, Billingsley G, Wilson MD, Zeitz C, Héon E, Vincent A. Phenotype Driven Analysis of Whole Genome Sequencing Identifies Deep Intronic Variants that Cause Retinal Dystrophies by Aberrant Exonization. Invest Ophthalmol Vis Sci 2020; 61:36. [PMID: 32881472 PMCID: PMC7443117 DOI: 10.1167/iovs.61.10.36] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/16/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To demonstrate the effectiveness of combining retinal phenotyping and focused variant filtering from genome sequencing (GS) in identifying deep intronic disease causing variants in inherited retinal dystrophies. Methods Affected members from three pedigrees with classical enhanced S-cone syndrome (ESCS; Pedigree 1), congenital stationary night blindness (CSNB; Pedigree 2), and achromatopsia (ACHM; Pedigree 3), respectively, underwent detailed ophthalmologic evaluation, optical coherence tomography, and electroretinography. The probands underwent panel-based genetic testing followed by GS analysis. Minigene constructs (NR2E3, GPR179 and CNGB3) and patient-derived cDNA experiments (NR2E3 and GPR179) were performed to assess the functional effect of the deep intronic variants. Results The electrophysiological findings confirmed the clinical diagnosis of ESCS, CSNB, and ACHM in the respective pedigrees. Panel-based testing revealed heterozygous pathogenic variants in NR2E3 (NM_014249.3; c.119-2A>C; Pedigree 1) and CNGB3 (NM_019098.4; c.1148delC/p.Thr383Ilefs*13; Pedigree 3). The GS revealed heterozygous deep intronic variants in Pedigrees 1 (NR2E3; c.1100+1124G>A) and 3 (CNGB3; c.852+4751A>T), and a homozygous GPR179 variant in Pedigree 2 (NM_001004334.3; c.903+343G>A). The identified variants segregated with the phenotype in all pedigrees. All deep intronic variants were predicted to generate a splice acceptor gain causing aberrant exonization in NR2E3 [89 base pairs (bp)], GPR179 (197 bp), and CNGB3 (73 bp); splicing defects were validated through patient-derived cDNA experiments and/or minigene constructs and rescued by antisense oligonucleotide treatment. Conclusions Deep intronic mutations contribute to missing heritability in retinal dystrophies. Combining results from phenotype-directed gene panel testing, GS, and in silico splice prediction tools can help identify these difficult-to-detect pathogenic deep intronic variants.
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Affiliation(s)
- Matteo Di Scipio
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Erika Tavares
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Shriya Deshmukh
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC1423, Paris, France
- University College London Institute of Ophthalmology, London, United Kingdom
| | - Kit Green-Sanderson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Yuliya Zubak
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Fayçal Zine-Eddine
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Alexander Pearson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anjali Vig
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Chen Yu Tang
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Antonio Mollica
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Jonathan Karas
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anupreet Tumber
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | - Caberry W. Yu
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Gail Billingsley
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Michael D. Wilson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Elise Héon
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
| | - Ajoy Vincent
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
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Wilgucki J, Williams PJ, Westfall E, Jain N, Yan J. Feasibility and Efficacy of Same-Day, In-Office Genetic Testing for Inherited Retinal Diseases. JOURNAL OF VITREORETINAL DISEASES 2020; 4:181-185. [PMID: 37007438 PMCID: PMC9982248 DOI: 10.1177/2474126419878145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
PURPOSE This article analyzes 2 practice patterns our institution uses for genetic testing of patients with inherited retinal diseases (IRDs) and compares testing completion and diagnostic yield rates. METHODS A retrospective, consecutive chart review series was conducted of patients with a clinically diagnosed rod-mediated IRD. All IRDs were diagnosed between 2 intervals: November 1, 2015, through November 30, 2016 (referral to a medical genetics clinic for testing) or December 1, 2016, through December 30, 2017 (same-day, in-office genetic testing). RESULTS A total of 189 patients were included in the study. Of patients who received an out-of-office referral for genetic testing, 10 of 84 (12%) patients proceeded with testing, whereas 74 of 84 (88%) patients did not complete testing. For patients who received in-office genetic testing, 104 of 105 (99%) completed testing. The difference in test completion was statistically significant (P < .001). In addition, genetic testing for out-of-office referrals identified a causative mutation in 5 of 10 (50%) patients, whereas in-office genetic testing identified a causative mutation in 42 of 104 (40.4%) patients. The difference in causative mutation discovery was not statistically significant (P = .18) between the 2 groups. CONCLUSIONS In-office genetic testing is a novel practice pattern that provides a more consistent and accessible method for IRD genetic diagnosis. Compared with an out-of-office referral for genetic testing, in-office genetic testing offers a similar rate of causative gene mutation identification but a greatly higher rate of test completion, therefore potentially offering a much higher yield for genetic diagnosis of IRDs.
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Jiman OA, Taylor RL, Lenassi E, Smith JC, Douzgou S, Ellingford JM, Barton S, Hardcastle C, Fletcher T, Campbell C, Ashworth J, Biswas S, Ramsden SC, Manson FD, Black GC. Diagnostic yield of panel-based genetic testing in syndromic inherited retinal disease. Eur J Hum Genet 2020; 28:576-586. [PMID: 31836858 PMCID: PMC7171123 DOI: 10.1038/s41431-019-0548-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/22/2019] [Accepted: 10/29/2019] [Indexed: 01/22/2023] Open
Abstract
Thirty percent of all inherited retinal disease (IRD) is accounted for by conditions with extra-ocular features. This study aimed to establish the genetic diagnostic pick-up rate for IRD patients with one or more extra-ocular features undergoing panel-based screening in a clinical setting. One hundred and six participants, tested on a gene panel which contained both isolated and syndromic IRD genes, were retrospectively ascertained from the Manchester Genomic Diagnostics Laboratory database spanning 6 years (2012-2017). Phenotypic features were extracted from the clinical notes and classified according to Human Phenotype Ontology; all identified genetic variants were interpreted in accordance to the American College of Medical Genetics and Genomics guidelines. Overall, 49% (n = 52) of patients received a probable genetic diagnosis. A further 6% (n = 6) had a single disease-associated variant in an autosomal recessive disease-relevant gene. Fifty-two percent (n = 55) of patients had a clinical diagnosis at the time of testing. Of these, 71% (n = 39) received a probable genetic diagnosis. By contrast, for those without a provisional clinical diagnosis (n = 51), only 25% (n = 13) received a probable genetic diagnosis. The clinical diagnosis of Usher (n = 33) and Bardet-Biedl syndrome (n = 10) was confirmed in 67% (n = 22) and 80% (n = 8), respectively. The testing diagnostic rate in patients with clinically diagnosed multisystemic IRD conditions was significantly higher than those without one (71% versus 25%; p value < 0.001). The lower pick-up rate in patients without a clinical diagnosis suggests that panel-based approaches are unlikely to be the most effective means of achieving a molecular diagnosis for this group. Here, we suggest that genome-wide approaches (whole exome or genome) are more appropriate.
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Affiliation(s)
- Omamah A Jiman
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Rachel L Taylor
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Eva Lenassi
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jill Clayton Smith
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Sofia Douzgou
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jamie M Ellingford
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Stephanie Barton
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Claire Hardcastle
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Tracy Fletcher
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Christopher Campbell
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jane Ashworth
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Susmito Biswas
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Simon C Ramsden
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Forbes D Manson
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
| | - Graeme C Black
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK.
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK.
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Nasser F, Kurtenbach A, Biskup S, Weidensee S, Kohl S, Zrenner E. Ophthalmic features of retinitis pigmentosa in Cohen syndrome caused by pathogenic variants in the VPS13B gene. Acta Ophthalmol 2020; 98:e316-e321. [PMID: 31580008 DOI: 10.1111/aos.14255] [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] [Received: 01/10/2019] [Accepted: 09/06/2019] [Indexed: 11/27/2022]
Abstract
PURPOSE The aim of this study is to report on the phenotype and genotype of five patients diagnosed with Cohen syndrome, an extremely rare autosomal recessive disorder manifesting with mental and physiological defects. METHODS Five patients from three German families and one Syrian family underwent a comprehensive ophthalmological examination. The scheduled visual acuity measurements, fundus ophthalmoscopy, spectral domain optical coherence tomography (OCT), full-field electrophysiological recordings of scotopic and photopic electroretinograms (ERGs) and colour vision testing could not be carried out in all subjects, because of the mental and physical retardation. The genetic diagnosis was achieved by next-generation sequencing. RESULTS The ophthalmic and systemic phenotype of the patients is typical for Cohen syndrome including myopia, night blindness, photophobia, fundus pigmentary changes and bull's eye maculopathy. Electroretinograms (ERGs) were extinguished in the four patients, whose recording was possible. Genetic testing revealed homozygous or two heterozygous bi-allelic mutations in the VPS13B (COH1) gene in all five patients, with five different allelic variants observed. The homozygous mutation c.6055_6056delGA; p.Asp2019Glnfs*15 in two sibling patients as well as the homozygous nonsense mutation c.8112C>G;p.Tyr2704* have not previously been reported. CONCLUSIONS The phenotype of the five patients reported here is typical for Cohen syndrome; however, their genotype is heterogeneous. Two new allelic variants were found to be the causative mutation.
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Affiliation(s)
- Fadi Nasser
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | - Anne Kurtenbach
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | | | | | - Susanne Kohl
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
| | - Eberhart Zrenner
- Centre for Ophthalmology University of Tuebingen Tuebingen Germany
- Werner Reichardt Centre for Integrative Neuroscience (CIN) University of Tuebingen Tuebingen Germany
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Feldhaus B, Weisschuh N, Nasser F, den Hollander AI, Cremers FP, Zrenner E, Kohl S, Zobor D. CEP290 Mutation Spectrum and Delineation of the Associated Phenotype in a Large German Cohort: A Monocentric Study. Am J Ophthalmol 2020; 211:142-150. [PMID: 31734136 DOI: 10.1016/j.ajo.2019.11.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 11/08/2019] [Accepted: 11/08/2019] [Indexed: 12/26/2022]
Abstract
PURPOSE Gene therapy for Leber congenital amaurosis (LCA) is becoming available, and therefore it is crucial to identify eligible candidates. We report the spectrum and associated phenotype of CEP290 mutations in the largest German cohort observed by a single clinical site. DESIGN Prospective cohort study. METHODS Twenty-three patients with mutations in CEP290 were included. Genomic DNA was analyzed by Sanger sequencing or high-throughput sequencing for all retinitis pigmentosa-associated genes in patients, and segregation analysis was done in family members. Patients underwent functional and morphologic examinations, including fundus autofluorescence and spectral-domain optical coherence tomography. RESULTS The most frequent mutation was c.2991+1655A>G, found in 87% of patients (20/23). Thirty percent of patients (7/23) carried the mutation in an apparent homozygous state and 57% (13/23) in a likely compound heterozygous state. The most common clinical diagnosis was LCA and/or early onset severe retinal dystrophy in 82% (19/23), followed by retinitis pigmentosa in 14% (3/23) and cone-rod dystrophy (4%, 1/23). Best-corrected visual acuity was severely reduced to residual light perception and hand motion vision, with the exception of 3 patients with best-corrected visual acuity of 0.8 (Snellen). The visual field was severely decreased and electroretinogram was undetectable in most cases; however, retinal layers at the fovea appeared to be relatively well preserved. Systemic disorders were not noticed. CONCLUSIONS c.2991+1655A>G is by far the most important CEP290 mutation, contributing to 87% of patients with the CEP290 mutation in Germany. In our cohort, a homozygous c.2991+1655A>G genotype presented with a more severe phenotype. National studies and further detailed phenotype analysis seem to be important to assess the need for and promise of specific gene therapies.
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Copy-number variation contributes 9% of pathogenicity in the inherited retinal degenerations. Genet Med 2020; 22:1079-1087. [PMID: 32037395 PMCID: PMC7272325 DOI: 10.1038/s41436-020-0759-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 01/27/2020] [Indexed: 11/08/2022] Open
Abstract
PURPOSE Current sequencing strategies can genetically solve 55-60% of inherited retinal degeneration (IRD) cases, despite recent progress in sequencing. This can partially be attributed to elusive pathogenic variants (PVs) in known IRD genes, including copy-number variations (CNVs), which have been shown as major contributors to unsolved IRD cases. METHODS Five hundred IRD patients were analyzed with targeted next-generation sequencing (NGS). The NGS data were used to detect CNVs with ExomeDepth and gCNV and the results were compared with CNV detection with a single-nucleotide polymorphism (SNP) array. Likely causal CNV predictions were validated by quantitative polymerase chain reaction (qPCR). RESULTS Likely disease-causing single-nucleotide variants (SNVs) and small indels were found in 55.6% of subjects. PVs in USH2A (11.6%), RPGR (4%), and EYS (4%) were the most common. Likely causal CNVs were found in an additional 8.8% of patients. Of the three CNV detection methods, gCNV showed the highest accuracy. Approximately 30% of unsolved subjects had a single likely PV in a recessive IRD gene. CONCLUSION CNV detection using NGS-based algorithms is a reliable method that greatly increases the genetic diagnostic rate of IRDs. Experimentally validating CNVs helps estimate the rate at which IRDs might be solved by a CNV plus a more elusive variant.
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Mutation spectrum of PRPF31, genotype-phenotype correlation in retinitis pigmentosa, and opportunities for therapy. Exp Eye Res 2020; 192:107950. [PMID: 32014492 PMCID: PMC7065041 DOI: 10.1016/j.exer.2020.107950] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 01/13/2020] [Accepted: 01/27/2020] [Indexed: 12/11/2022]
Abstract
Pathogenic variants in pre-messenger RNA (pre-mRNA) splicing factor 31, PRPF31, are the second most common genetic cause of autosomal dominant retinitis pigmentosa (adRP) in most populations. This remains a completely untreatable and incurable form of blindness, and it can be difficult to predict the clinical course of disease. In order to design appropriate targeted therapies, a thorough understanding of the genetics and molecular mechanism of this disease is required. Here, we present the structure of the PRPF31 gene and PRPF31 protein, current understanding of PRPF31 protein function and the full spectrum of all reported clinically relevant variants in PRPF31. We delineate the correlation between specific PRPF31 genotype and RP phenotype, suggesting that, except in cases of complete gene deletion or large-scale deletions, dominant negative effects contribute to phenotype as well as haploinsufficiency. This has important impacts on design of targeted therapies, particularly the feasibility of gene augmentation as a broad approach for treatment of PRPF31-associated RP. We discuss other opportunities for therapy, including antisense oligonucleotide therapy and gene-independent approaches and offer future perspectives on treatment of this form of RP. PRPF31 is the second most common cause of autosomal dominant retinitis pigmentosa and a potential target for gene therapy. We present all reported pathogenic variants in PRPF31 as a resource for clinicians, diagnostic genetics labs, and researchers. Genotype-phenotype correlations suggest that, dominant negative effects contribute to disease in addition to haploinsufficiency. This finding has important impacts on the suitability of gene augmentation approaches across all mutation types. This finding may aid prognosis of disease in PRPF31-associated RP patients.
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Nasser F, Kempf M, Kurtenbach A, Stöhr H, Weber BHF, Neuhaus C, Rating P, Zrenner E. Correlating Adaptive Optics Images to Clinical Findings in Juvenile Macular Dystrophy with Hypotrichosis in Siblings with Homozygous CDH3 Pathogenic Variation. Ophthalmic Res 2020; 63:141-151. [PMID: 31927556 DOI: 10.1159/000504757] [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: 08/19/2019] [Accepted: 11/10/2019] [Indexed: 11/19/2022]
Abstract
OBJECTIVE We report on two German siblings diagnosed with congenital hypotrichosis and juvenile macular dystrophy, an extremely rare syndrome affecting both hair growth and visual functions. METHODS A detailed ophthalmological examination was carried out including fundus examination, visual acuity assessment, visual field determination, color vision testing, and electrophysiology (electroretinography [ERG]). Additionally, fundus photography and autofluorescence imaging (FAF) was performed, along with optical coherence tomography (OCT) and adaptive optics (AO) fundus imaging. Targeted Sanger sequencing and next-generation gene panel sequencing were carried out. RESULTS Macular dystrophy was evident in the fundus of both patients, as was a central scotoma in the static visual field. The kinetic visual field was normal. The ERG recordings were also normal, but the amplitudes of the multifocal ERG were reduced in the central 4-5° of the retina. The FAF images revealed a large central hypofluorescent area surrounded by a hyperfluorescent ring. The OCT images showed atrophy in the outer layers and tubulations. The AO images depicted a loss of central photoreceptors, as well as severe central atrophy in patient 1. A cone mosaic was observable in the peripheral AO fundus images of both patients. The disrupted cone mosaic on the AO images correlated with the hypofluorescent areas on autofluorescence. DNA testing identified the homozygous, likely pathogenic variant c.1508G>A/p.(Arg503His) (chr16:68719191) in the CDH3 gene. CONCLUSIONS The two siblings revealed hypotrichosis and macular dystrophy in both eyes. The identification of a homozygous CDH3 mutation in each patient confirms the syndromic entity of hypotrichosis with juvenile macular degeneration.
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Affiliation(s)
- Fadi Nasser
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany,
| | - Melanie Kempf
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Anne Kurtenbach
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Heidi Stöhr
- Institute of Human Genetics, Universität Regensburg, Regensburg, Germany
| | - Bernhard H F Weber
- Institute of Human Genetics, Universität Regensburg, Regensburg, Germany
| | - Christine Neuhaus
- Bioscientia Institute for Medical Diagnostic GmbH, Ingelheim am Rhein, Germany
| | - Philipp Rating
- Department of Ophthalmology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Eberhart Zrenner
- Institute for Ophthalmic Research, Center for Ophthalmology, University of Tübingen, Tübingen, Germany.,Werner Reichardt Center for Integrative Neuroscience (CIN), University of Tübingen, Tübingen, Germany
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Mayer AK, Balousha G, Sharkia R, Mahajnah M, Ayesh S, Schulze M, Buchert R, Zobor D, Azem A, Schöls L, Bauer P, Wissinger B. Unraveling the genetic cause of hereditary ophthalmic disorders in Arab societies from Israel and the Palestinian Authority. Eur J Hum Genet 2020; 28:742-753. [PMID: 31896775 DOI: 10.1038/s41431-019-0566-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 11/12/2019] [Accepted: 12/10/2019] [Indexed: 11/09/2022] Open
Abstract
Visual impairment due to inherited ophthalmic disorders is amongst the most common disabilities observed in populations practicing consanguineous marriages. Here we investigated the molecular genetic basis of an unselected broad range of ophthalmic disorders in 20 consanguineous families from Arab villages of Israel and the Palestinian Authority. Most patients had little or very poor prior clinical workup and were recruited in a field study. Homozygosity mapping followed by candidate gene sequencing applying conventional Sanger sequencing or targeted next generation sequencing was performed in six families. In the remaining 14 families, one affected subject per family was chosen for whole exome sequencing. We discovered likely disease-causing variants, all homozygous, in 19 of 20 independent families (95%) including a previously reported novel disease gene for congenital nystagmus associated with foveal hypoplasia. Moreover, we found a family in which disease-causing variants for two collagenopathies - Stickler and Knobloch syndrome - segregate within a large sibship. Nine of the 19 distinct variants observed in this study were novel. Our study demonstrated a very high molecular diagnostic yield for a highly diverse spectrum of rare ophthalmic disorders in Arab patients from Israel and the Palestinian Authority, even with very limited prior clinical investigation. We conclude that 'genetic testing first' may be an economic way to direct clinical care and to support proper genetic counseling and risk assessment in these families.
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Affiliation(s)
- Anja K Mayer
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany.,Praxis fuer Humangenetik Tuebingen, Tuebingen, Germany
| | - Ghassan Balousha
- Department of Pathology and Histology, Al-Quds University, Eastern Jerusalem, Palestinian Authority, Jerusalem, Israel
| | - Rajech Sharkia
- The Triangle Regional Research and Development Center, Kfar Qari', Israel.,Beit-Berl Academic College, Beit-Berl, Israel
| | - Muhammad Mahajnah
- Child Neurology and Development Center, Hillel-Yaffe Medical Center, Hadera, Israel.,The Ruth and Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Suhail Ayesh
- Molecular Genetic Laboratory, Al-Makassed Islamic Charitable Society Hospital, Jerusalem, Israel
| | - Martin Schulze
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany.,Praxis fuer Humangenetik Tuebingen, Tuebingen, Germany
| | - Rebecca Buchert
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Ditta Zobor
- University Eye Hospital, University of Tuebingen, Tuebingen, Germany
| | - Abdussalam Azem
- The School of Neurobiology, Biochemistry and Biophysics, George S. Wise faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Ludger Schöls
- Hertie Institute for Brain Research, University of Tuebingen, Tuebingen, Germany.,German Center of Neurodegenerative Diseases (DZNE), Tuebingen, Germany
| | - Peter Bauer
- Institute of Medical Genetics and Applied Genomics, University of Tuebingen, Tuebingen, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany.
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Stingl KT, Kuehlewein L, Weisschuh N, Biskup S, Cremers FPM, Khan MI, Kelbsch C, Peters T, Ueffing M, Wilhelm B, Zrenner E, Stingl K. Chromatic Full-Field Stimulus Threshold and Pupillography as Functional Markers for Late-Stage, Early-Onset Retinitis Pigmentosa Caused by CRB1 Mutations. Transl Vis Sci Technol 2019; 8:45. [PMID: 31879567 PMCID: PMC6927735 DOI: 10.1167/tvst.8.6.45] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 09/30/2019] [Indexed: 01/08/2023] Open
Abstract
Purpose Mutations in the CRB1 gene cause early-onset retinal degeneration (EORD). Clinical disease progression markers, such as visual fields or electrophysiology, are not reliably measurable in most patients to follow the retinal function in patients with CRB1-mutations. Methods Ten patients (five females, five males; age 22–56 years) with EORD caused by CRB1 mutations were examined in a cross-sectional manner using best corrected visual acuity (BCVA), perimetry, full-field and multifocal electroretinography, full-field stimulus threshold (FST), and pupillography to red and blue light. Disease duration was defined as the difference between the age at the first symptoms to the age at examination in years. Results BCVA was quantifiable in six patients and ranged from light perception to 20/50. The visual field was measurable only in three patients who had the shortest disease duration. Full-field and multifocal electroretinography were not measurable in any patient. FST to blue and red light were measurable in all patients except the one with the longest disease duration; the thresholds ranged from −16.7 to 1.5 dB for red light and from −40.2 to 2.5 dB for blue light (0 dB = 0.01 cd.s/m2) and showed correlations with disease duration (r = 0.87 for blue, r = 0.65 for red, r = 0.8 for blue–red difference). The maximal relative pupil constriction amplitude (MRA) showed low or no correlations with disease duration (r = −0.55 for blue, r = −0.3 for red light); the blue–red difference in the post-illumination pupil responses (PIPR) showed no correlation with disease duration (r = −0.05). Compared to healthy eyes, the MRA to red and blue light was significantly decreased (P < 0.001) and the blue–red PIPR difference was significantly increased (P = 0.003). Conclusions FST features a valid clinical marker in late-stage early-onset retinitis pigmentosa caused by CRB1 mutations correlating with disease duration. This indicates the potential as a progression marker of disease. The pupil responses to full-field chromatic stimuli show significant differences from the normal population: the remaining responses, although reduced, indicate a partially preserved inner retinal function despite severe photoreceptor dysfunction. Translational Relevance The functional measurements presented in this study present a valid clinical progression marker in late-stage early onset retinitis pigmentosa caused by biallelic CRB1 mutations. Additionally, they can be used as outcome measures for safety and efficacy in clinical therapy trials.
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Affiliation(s)
| | - Laura Kuehlewein
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Nicole Weisschuh
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | | | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center and Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
| | - M Imran Khan
- Department of Human Genetics, Radboud University Medical Center and Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
| | - Carina Kelbsch
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Tobias Peters
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Marius Ueffing
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Barbara Wilhelm
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Eberhart Zrenner
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany.,Werner Reichardt Center for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
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38
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Mizobuchi K, Hayashi T, Katagiri S, Yoshitake K, Fujinami K, Yang L, Kuniyoshi K, Shinoda K, Machida S, Kondo M, Ueno S, Terasaki H, Matsuura T, Tsunoda K, Iwata T, Nakano T. Characterization of GUCA1A-associated dominant cone/cone-rod dystrophy: low prevalence among Japanese patients with inherited retinal dystrophies. Sci Rep 2019; 9:16851. [PMID: 31728034 PMCID: PMC6856191 DOI: 10.1038/s41598-019-52660-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/21/2019] [Indexed: 12/14/2022] Open
Abstract
GUCA1A gene variants are associated with autosomal dominant (AD) cone dystrophy (COD) and cone-rod dystrophy (CORD). GUCA1A-associated AD-COD/CORD has never been reported in the Japanese population. The purpose of this study was to investigate clinical and genetic features of GUCA1A-associated AD-COD/CORD from a large Japanese cohort. We identified 8 variants [c.C50_80del (p.E17VfsX22), c.T124A (p.F42I), c.C204G (p.D68E), c.C238A (p.L80I), c.T295A (p.Y99N), c.A296C (p.Y99S), c.C451T (p.L151F), and c.A551G (p.Q184R)] in 14 families from our whole exome sequencing database composed of 1385 patients with inherited retinal diseases (IRDs) from 1192 families. Three variants (p.Y99N, p.Y99S, and p.L151F), which are located on/around EF-hand domains 3 and 4, were confirmed as "pathogenic", whereas the other five variants, which did not co-segregate with IRDs, were considered "non-pathogenic". Ophthalmic findings of 9 patients from 3 families with the pathogenic variants showed central visual impairment from early to middle-age onset and progressive macular atrophy. Electroretinography revealed severely decreased or non-recordable cone responses, whereas rod responses were highly variable, ranging from nearly normal to non-recordable. Our results indicate that the three pathogenic variants, two of which were novel, underlie AD-COD/CORD with progressive retinal atrophy, and the prevalence (0.25%, 3/1192 families) of GUCA1A-associated IRDs may be low among Japanese patients.
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Affiliation(s)
- Kei Mizobuchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan. .,Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, Tokyo, Japan.
| | - Satoshi Katagiri
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Kazutoshi Yoshitake
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Kaoru Fujinami
- Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.,UCL Institute of Ophthalmology associated with Moorfields Eye Hospital, London, UK
| | - Lizhu Yang
- Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuki Kuniyoshi
- Department of Ophthalmology, Kindai University Faculty of Medicine, Osaka, Japan
| | - Kei Shinoda
- Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan
| | - Shigeki Machida
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, Saitama, Japan.,Department of Ophthalmology, Iwate Medical University School of Medicine, Iwate, Japan
| | - Mineo Kondo
- Department of Ophthalmology, Mie University Graduate School of Medicine, Mie, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Aichi, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Aichi, Japan
| | - Tomokazu Matsuura
- Department of Laboratory Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Kazushige Tsunoda
- Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Takeshi Iwata
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
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Mirza M, Vainshtein A, DiRonza A, Chandrachud U, Haslett LJ, Palmieri M, Storch S, Groh J, Dobzinski N, Napolitano G, Schmidtke C, Kerkovich DM. The CLN3 gene and protein: What we know. Mol Genet Genomic Med 2019; 7:e859. [PMID: 31568712 PMCID: PMC6900386 DOI: 10.1002/mgg3.859] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 12/11/2022] Open
Abstract
Background One of the most important steps taken by Beyond Batten Disease Foundation in our quest to cure juvenile Batten (CLN3) disease is to understand the State of the Science. We believe that a strong understanding of where we are in our experimental understanding of the CLN3 gene, its regulation, gene product, protein structure, tissue distribution, biomarker use, and pathological responses to its deficiency, lays the groundwork for determining therapeutic action plans. Objectives To present an unbiased comprehensive reference tool of the experimental understanding of the CLN3 gene and gene product of the same name. Methods BBDF compiled all of the available CLN3 gene and protein data from biological databases, repositories of federally and privately funded projects, patent and trademark offices, science and technology journals, industrial drug and pipeline reports as well as clinical trial reports and with painstaking precision, validated the information together with experts in Batten disease, lysosomal storage disease, lysosome/endosome biology. Results The finished product is an indexed review of the CLN3 gene and protein which is not limited in page size or number of references, references all available primary experiments, and does not draw conclusions for the reader. Conclusions Revisiting the experimental history of a target gene and its product ensures that inaccuracies and contradictions come to light, long‐held beliefs and assumptions continue to be challenged, and information that was previously deemed inconsequential gets a second look. Compiling the information into one manuscript with all appropriate primary references provides quick clues to which studies have been completed under which conditions and what information has been reported. This compendium does not seek to replace original articles or subtopic reviews but provides an historical roadmap to completed works.
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Affiliation(s)
| | | | - Alberto DiRonza
- Baylor College of Medicine, Houston, Texas.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas
| | - Uma Chandrachud
- Center for Genomic Medicine, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts
| | | | - Michela Palmieri
- Baylor College of Medicine, Houston, Texas.,Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas
| | - Stephan Storch
- Biochemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Janos Groh
- Neurology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Niv Dobzinski
- Biochemistry and Biophysics, UCSF School of Medicine, San Francisco, California
| | | | - Carolin Schmidtke
- Biochemistry, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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40
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The Oculome Panel Test: Next-Generation Sequencing to Diagnose a Diverse Range of Genetic Developmental Eye Disorders. Ophthalmology 2019; 126:888-907. [PMID: 30653986 DOI: 10.1016/j.ophtha.2018.12.050] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 12/18/2018] [Accepted: 12/21/2018] [Indexed: 01/09/2023] Open
Abstract
PURPOSE To develop a comprehensive next-generation sequencing panel assay that screens genes known to cause developmental eye disorders and inherited eye disease and to evaluate its diagnostic yield in a pediatric cohort with malformations of the globe, anterior segment anomalies, childhood glaucoma, or a combination thereof. DESIGN Evaluation of diagnostic test. PARTICIPANTS Two hundred seventy-seven children, 0 to 16 years of age, diagnosed with nonsyndromic or syndromic developmental eye defects without a genetic diagnosis. METHODS We developed a new oculome panel using a custom-designed Agilent SureSelect QXT target capture method (Agilent Technologies, Santa Clara, CA) to capture and perform parallel high-throughput sequencing analysis of 429 genes associated with eye disorders. Bidirectional Sanger sequencing confirmed suspected pathogenic variants. MAIN OUTCOME MEASURES Collated clinical details and oculome molecular genetic results. RESULTS The oculome design covers 429 known eye disease genes; these are subdivided into 5 overlapping virtual subpanels for anterior segment developmental anomalies including glaucoma (ASDA; 59 genes), microphthalmia-anophthalmia-coloboma (MAC; 86 genes), congenital cataracts and lens-associated conditions (70 genes), retinal dystrophies (RET; 235 genes), and albinism (15 genes), as well as additional genes implicated in optic atrophy and complex strabismus (10 genes). Panel development and testing included analyzing 277 clinical samples and 3 positive control samples using Illumina sequencing platforms; more than 30× read depth was achieved for 99.5% of the targeted 1.77-Mb region. Bioinformatics analysis performed using a pipeline based on Freebayes and ExomeDepth to identify coding sequence and copy number variants, respectively, resulted in a definitive diagnosis in 68 of 277 samples, with variability in diagnostic yield between phenotypic subgroups: MAC, 8.2% (8 of 98 cases solved); ASDA, 24.8% (28 of 113 cases solved); other or syndromic, 37.5% (3 of 8 cases solved); RET, 42.8% (21 of 49 cases solved); and congenital cataracts and lens-associated conditions, 88.9% (8 of 9 cases solved). CONCLUSIONS The oculome test diagnoses a comprehensive range of genetic conditions affecting the development of the eye, potentially replacing protracted and costly multidisciplinary assessments and allowing for faster targeted management. The oculome enabled molecular diagnosis of a significant number of cases in our sample cohort of varied ocular birth defects.
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41
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A case of X-linked retinoschisis with atypical fundus appearance. Doc Ophthalmol 2019; 139:75-81. [PMID: 31006083 DOI: 10.1007/s10633-019-09698-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 04/10/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE Mutations in the RS1 gene are known to cause retinoschisis, an X-linked hereditary retinal degeneration. Here, we present a case of atypical retinoschisis with clinical findings of retinoschisis and retinitis pigmentosa. METHODS This report is an observational case report. The detailed ophthalmological examinations included visual field determination, multimodal imaging and electrophysiological recordings. Targeted next-generation sequencing of a retinal disease gene panel was performed. RESULTS The 55-year-old male, highly hyperopic patient, presented with a best-corrected Snellen visual acuity of 20/100 in the right eye and 20/400 in the left eye. In the kinetic visual field, there was a superior scotoma, as well as a ring scotoma in the inferior hemisphere in the right eye and a concentric visual field constriction to 10° in the left eye. Funduscopy revealed marked pigmentary changes (i.e. bone spicules) in the mid-periphery bilaterally and symmetrically, as well as two small intra-retinal haemorrhages in the left eye. Full-field electroretinography recordings showed extinguished rod and cone responses. Diagnostic-genetic testing revealed a hemizygous missense mutation in the RS1 gene (c.305G > A; p.Arg102Gln) was identified. CONCLUSION We present a case of atypical retinoschisis with clinical findings of retinitis pigmentosa.
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Liu S, Bi JG, Hu Y, Tang D, Li B, Zhu P, Peng W, Du D, He H, Zeng J, Dai Y. Targeted next generation sequencing identified novel loss-of-function mutations in MERTK gene in Chinese patients with retinitis pigmentosa. Mol Genet Genomic Med 2019; 7:e00577. [PMID: 30790467 PMCID: PMC6465654 DOI: 10.1002/mgg3.577] [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: 08/06/2018] [Accepted: 01/03/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Retinitis pigmentosa (RP) is one of the major types of hereditary retinal dystrophies with extreme genotypic heterogeneity. To date, more than 80 genes have been identified to be associated with RP in human. METHOD Here, we presented a clinical genetic study of three Chinese man manifested with night vision blindness and complete loss of midperipheral visual field. All of these three probands have been identified with loss of both central vision and far peripheral visual field. Gradual loss of rod cells followed by subsequent loss of cone cells have been identified in these probands. Targeted next generation sequencing and Sanger sequencing have been performed to understand the pathogenic variants underlying the disease phenotype in these three unrelated Chinese probands. RESULTS Targeted next generation sequencing and Sanger sequencing identified three homozygous novel mutations (c.1880C>A; c.1459_1460delGA, and c.392G>A) in the MERTK gene in these three unrelated Chinese proband. In the first proband, the identified mutation (c.1880C>A) leads to the formation of a premature stop codon followed by the formation of a truncated mer-tyrosine kinase (MERTK) protein (p.Ser627*) product which predicted to be disease causing. In the second proband, the identified deletion (c.1459_1460delGA) leads to the formation of a frameshift which also finally results in the formation of a truncated MERTK protein (p.Asp487Leufs*57) product which also predicted to be disease causing. In the third proband, the identified mutation (c.392G>A) leads to the formation of a premature stop codon followed by the formation of a truncated MERTK protein (p.Trp131*) product which also predicted to be disease causing. Hence, these three mutations are loss-of-function mutations. These three mutations were absent in unaffected family members and in 100 normal healthy controls. CONCLUSION Our present study also demonstrates the significance of targeted next generation sequencing in determining the genetic basis of RP.
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Affiliation(s)
- Song Liu
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Jian Gang Bi
- Department of Hepatobiliary Surgery, The Second Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, China
| | - Yunlong Hu
- Department of Pathogen Biology, Shenzhen University School of Medicine, Shenzhen, R.P. China
| | - Donge Tang
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Bo Li
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Peng Zhu
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Wujian Peng
- The Third People's Hospital of Shenzhen, Clinical Medical Research Center, Shenzhen, Guangdong, R.P. China
| | - Dong Du
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Huiyan He
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Jun Zeng
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
| | - Yong Dai
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University (Shenzhen People's Hospital), Shenzhen, Guangdong, R.P. China
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Tayebi N, Akinrinade O, Khan MI, Hejazifar A, Dehghani A, Cremers FP, Akhlaghi M. Targeted next generation sequencing reveals genetic defects underlying inherited retinal disease in Iranian families. Mol Vis 2019; 25:106-117. [PMID: 30820146 PMCID: PMC6377375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/06/2019] [Indexed: 11/15/2022] Open
Abstract
Purpose Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous showing progressive retinal cell death which results in vision loss. IRDs include a wide spectrum of disorders, such as retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), cone-rod dystrophy (CRD), and Stargardt disease (STGD1). Methods In this study, we performed targeted next-generation sequencing based on molecular inversion probes (MIPs) that allowed the sequence analysis of 108 IRD-associated genes in 50 Iranian IRD probands. Results The sequencing and variant filtering led to the identification of putative pathogenic variants in 36 out of 50 (72%) probands. Among 36 unique variants, we identified 20 novel variants in 15 genes. Four out of 36 probands carry compound heterozygous variants, and 32 probands carry homozygous variants. Conclusions Employing a cost-effective targeted next-generation sequencing procedure, we identified the genetic causes of different retinal disorders in the majority of Iranian families in this study.
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Affiliation(s)
- Naeimeh Tayebi
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Oyediran Akinrinade
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Muhammad Imran 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
| | - Arash Hejazifar
- Department of Biology, School of Sciences, The University of Isfahan, Isfahan, Iran
| | - Alireza Dehghani
- Department of Ophthalmology, Isfahan Eye Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - 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
| | - Mohammadreza Akhlaghi
- Department of Ophthalmology, Isfahan Eye Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
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Azab B, Barham R, Ali D, Dardas Z, Rashdan L, Bijawi M, Maswadi R, Awidi A, Jafar H, Abu-Ameerh M, Al-Bdour M, Amr S, Awidi A. Novel CERKL variant in consanguineous Jordanian pedigrees with inherited retinal dystrophies. Can J Ophthalmol 2019; 54:51-59. [DOI: 10.1016/j.jcjo.2018.02.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 02/24/2018] [Accepted: 02/27/2018] [Indexed: 01/02/2023]
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Nasser F, Mulahasanovic L, Alkhateeb M, Biskup S, Stingl K, Zrenner E. Hypotrichosis with cone-rod dystrophy in a patient with cadherin 3 (CDH3) mutation. Doc Ophthalmol 2019; 138:153-160. [PMID: 30710256 DOI: 10.1007/s10633-019-09675-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/26/2019] [Indexed: 12/11/2022]
Abstract
PURPOSE To investigate a very rare case of hypotrichosis with cone-rod dystrophy caused by a P-cadherin CDH3 mutation. METHODS A 16-year-old Syrian girl was examined at age 9 and 14 years with an ophthalmological examination, fundus imaging, OCT and electrophysiological recordings (ERG and PERG). A disease-targeted gene panel sequencing was performed. RESULTS Fundus images showed pigmentations at the posterior eye pole to the mid periphery, as well as vessel tortuosity. OCT images revealed a loss of the outer retinal segments and IS/OS in the central macula. The scotopic and photopic ERGs showed moderately reduced amplitudes at age 9 years that became severely reduced at age of 14 years. The PERG was undetectable at age 9 years. In color vision testing, protan-deutan confusion errors occurred. Gene panel analysis revealed one homozygous mutation in CDH3 (c.1508G>A; p.Arg503His). CONCLUSION This case shows that a CDH3 mutation besides macula dystrophy can cause widespread cone-rod dystrophy with hypotrichosis without any other pathology besides hypoplastic nails. This points to a common pathway of hair growth and photoreceptor development that can be disturbed by a CDH3 mutation (c.1508G>A; p.Arg503His) located in the EC4 repeat region of the gene.
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Affiliation(s)
- F Nasser
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Elfriede-Aulhorn Strasse 7, 72076, Tübingen, Germany.
| | - L Mulahasanovic
- Praxis for Human Genetics, Tübingen, Germany.,CeGaT GmbH, Tübingen, Germany
| | - M Alkhateeb
- Eye and Ear Specialty Hospital, Damascus, Syria
| | - S Biskup
- Praxis for Human Genetics, Tübingen, Germany.,CeGaT GmbH, Tübingen, Germany
| | - K Stingl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Elfriede-Aulhorn Strasse 7, 72076, Tübingen, Germany
| | - E Zrenner
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tuebingen, Elfriede-Aulhorn Strasse 7, 72076, Tübingen, Germany.,Werner Reichardt Center for Integrative Neuroscience (CIN), University of Tuebingen, Tübingen, Germany
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Phenotypic spectrum of autosomal recessive retinitis pigmentosa without posterior column ataxia caused by mutations in the FLVCR1 gene. Graefes Arch Clin Exp Ophthalmol 2019; 257:629-638. [DOI: 10.1007/s00417-018-04233-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 12/20/2018] [Accepted: 12/23/2018] [Indexed: 10/27/2022] Open
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Burkard M, Kohl S, Krätzig T, Tanimoto N, Brennenstuhl C, Bausch AE, Junger K, Reuter P, Sothilingam V, Beck SC, Huber G, Ding XQ, Mayer AK, Baumann B, Weisschuh N, Zobor D, Hahn GA, Kellner U, Venturelli S, Becirovic E, Charbel Issa P, Koenekoop RK, Rudolph G, Heckenlively J, Sieving P, Weleber RG, Hamel C, Zong X, Biel M, Lukowski R, Seeliger MW, Michalakis S, Wissinger B, Ruth P. Accessory heterozygous mutations in cone photoreceptor CNGA3 exacerbate CNG channel-associated retinopathy. J Clin Invest 2018; 128:5663-5675. [PMID: 30418171 PMCID: PMC6264655 DOI: 10.1172/jci96098] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 10/02/2018] [Indexed: 01/01/2023] Open
Abstract
Mutations in CNGA3 and CNGB3, the genes encoding the subunits of the tetrameric cone photoreceptor cyclic nucleotide-gated ion channel, cause achromatopsia, a congenital retinal disorder characterized by loss of cone function. However, a small number of patients carrying the CNGB3/c.1208G>A;p.R403Q mutation present with a variable retinal phenotype ranging from complete and incomplete achromatopsia to moderate cone dysfunction or progressive cone dystrophy. By exploring a large patient cohort and published cases, we identified 16 unrelated individuals who were homozygous or (compound-)heterozygous for the CNGB3/c.1208G>A;p.R403Q mutation. In-depth genetic and clinical analysis revealed a co-occurrence of a mutant CNGA3 allele in a high proportion of these patients (10 of 16), likely contributing to the disease phenotype. To verify these findings, we generated a Cngb3R403Q/R403Q mouse model, which was crossbred with Cnga3-deficient (Cnga3-/-) mice to obtain triallelic Cnga3+/- Cngb3R403Q/R403Q mutants. As in human subjects, there was a striking genotype-phenotype correlation, since the presence of 1 Cnga3-null allele exacerbated the cone dystrophy phenotype in Cngb3R403Q/R403Q mice. These findings strongly suggest a digenic and triallelic inheritance pattern in a subset of patients with achromatopsia/severe cone dystrophy linked to the CNGB3/p.R403Q mutation, with important implications for diagnosis, prognosis, and genetic counseling.
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Affiliation(s)
- Markus Burkard
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
- Department of Vegetative and Clinical Physiology
| | - Susanne Kohl
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Timm Krätzig
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
| | - Naoyuki Tanimoto
- Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | | | - Anne E. Bausch
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
| | - Katrin Junger
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
| | - Peggy Reuter
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Vithiyanjali Sothilingam
- Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Susanne C. Beck
- Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Gesine Huber
- Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Xi-Qin Ding
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Anja K. Mayer
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Britta Baumann
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Nicole Weisschuh
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Ditta Zobor
- Institute of Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Gesa-Astrid Hahn
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Ulrich Kellner
- Rare Retinal Disease Center, Augenzentrum Siegburg, MVZ ADTC Siegburg GmbH, Siegburg, Germany
| | | | - Elvir Becirovic
- Center for Integrated Protein Science Munich CiPSM and Department of Pharmacy–Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Peter Charbel Issa
- Oxford Eye Hospital, OUH NHS Foundation Trust and the Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Robert K. Koenekoop
- McGill Ocular Genetics Centre, McGill University Health Centre, Montreal, Quebec, Canada
| | | | | | - Paul Sieving
- The National Eye Institute, Bethesda, Maryland, USA
| | - Richard G. Weleber
- Casey Eye Institute, Department of Ophthalmogenetics, Portland, Oregon, USA
| | - Christian Hamel
- INSERM U583, Institut des Neurosciences, Montpellier, France
| | - Xiangang Zong
- Center for Integrated Protein Science Munich CiPSM and Department of Pharmacy–Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Martin Biel
- Center for Integrated Protein Science Munich CiPSM and Department of Pharmacy–Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Robert Lukowski
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
| | - Matthias W. Seeliger
- Division of Ocular Neurodegeneration, Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Stylianos Michalakis
- Center for Integrated Protein Science Munich CiPSM and Department of Pharmacy–Center for Drug Research, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Bernd Wissinger
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, and
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy
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Ravesh Z, Dianatpour M, Fardaei M, Taghdiri M, Hashemi-Gorji F, Yassaee VR, Miryounesi M. Advanced molecular approaches pave the road to a clear-cut diagnosis of hereditary retinal dystrophies. Mol Vis 2018; 24:679-689. [PMID: 30416334 PMCID: PMC6197863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 10/17/2018] [Indexed: 11/18/2022] Open
Abstract
Purpose The aim of this study was to identify the molecular genetic basis of hereditary retinal dystrophies (HRDs) in five unrelated Iranian families. Methods Whole exome sequencing and Sanger sequencing were performed in all families. Variants were analyzed using various bioinformatics databases and software. Results Based on the selected strategies, we identified potentially causative variants in five families with HRDs: the novel homozygous deletion mutation c.586_589delTTTG (p.F196Sfs*56) in the TTC8 gene of family A, the novel homozygous missense mutation c.2389T>C (p.S797P) in the CRB1 gene in family B, the novel homozygous frameshift mutation c.2707dupA (p.S903Kfs*66) in the LRP5 gene in family C, the novel homozygous splice mutation c.584-1G>T in the MERTK gene in family D, and the novel homozygous missense mutation c.1819G>C (p.G607R) rs61749412 in the ABCA4 gene of family E. Conclusions This study highlights the presence of five novel variants associated with retinal dystrophies in selected Iranian families with hereditary blindness.
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Affiliation(s)
- Zeinab Ravesh
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahdi Dianatpour
- Department of Medical Genetics, School of Medical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Majid Fardaei
- Department of Medical Genetics, School of Medical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Maryam Taghdiri
- Comprehensive Medical Genetic Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Vahid Reza Yassaee
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Miryounesi
- Genomic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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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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González-Del Pozo M, Martín-Sánchez M, Bravo-Gil N, Méndez-Vidal C, Chimenea Á, Rodríguez-de la Rúa E, Borrego S, Antiñolo G. Searching the second hit in patients with inherited retinal dystrophies and monoallelic variants in ABCA4, USH2A and CEP290 by whole-gene targeted sequencing. Sci Rep 2018; 8:13312. [PMID: 30190494 PMCID: PMC6127285 DOI: 10.1038/s41598-018-31511-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/20/2018] [Indexed: 12/19/2022] Open
Abstract
Inherited Retinal Dystrophies are clinically and genetically heterogeneous disorders affecting the photoreceptors. Although NGS has shown to be helpful for the molecular diagnosis of these conditions, some cases remain unsolved. Among these, several individuals harboured monoallelic variants in a recessive gene, suggesting that a comprehensive screening could improve the overall diagnosis. In order to assess the contribution of non-coding variations in a cohort of 29 patients, 25 of them with monoallelic mutations, we performed targeted NGS. The design comprised the entire genomic sequence of three genes (USH2A, ABCA4 and CEP290), the coding exons of 76 genes and two disease-associated intronic regions in OFD1 and PRPF31. As a result, likely causative mutations (8 novel) were identified in 17 probands (diagnostic rate: 58.62%), including two copy-number variations in USH2A (one deletion of exons 22-55 and one duplication of exons 46-47). Possibly damaging deep-intronic mutations were identified in one family, and another with a monoallelic variant harboured causal mutations in a different locus. In conclusion, due to the high prevalence of carriers of IRD mutations and the results obtained here, sequencing entire genes do not seem to be the approach of choice for detecting the second hit in IRD patients with monoallelic variants.
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Affiliation(s)
- María González-Del Pozo
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain
| | - Marta Martín-Sánchez
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
| | - Nereida Bravo-Gil
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain
| | - Cristina Méndez-Vidal
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain
| | - Ángel Chimenea
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
| | - Enrique Rodríguez-de la Rúa
- Department of Ophthalmology, University Hospital Virgen Macarena, Seville, Spain
- Retics Patologia Ocular. OFTARED. Instituto de Salud Carlos III, Madrid, Spain
| | - Salud Borrego
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain
| | - Guillermo Antiñolo
- Department of Maternofetal Medicine, Genetics and Reproduction, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío/CSIC/University of Seville, Seville, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain.
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