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He X, Fu Y, Ma L, Yao Y, Ge S, Yang Z, Fan X. AAV for Gene Therapy in Ocular Diseases: Progress and Prospects. RESEARCH (WASHINGTON, D.C.) 2023; 6:0291. [PMID: 38188726 PMCID: PMC10768554 DOI: 10.34133/research.0291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 11/27/2023] [Indexed: 01/09/2024]
Abstract
Owing to the promising therapeutic effect and one-time treatment advantage, gene therapy may completely change the management of eye diseases, especially retinal diseases. Adeno-associated virus (AAV) is considered one of the most promising viral gene delivery tools because it can infect various types of tissues and is considered as a relatively safe gene delivery vector. The eye is one of the most popular organs for gene therapy, since its limited volume is suitable for small doses of AAV stably transduction. Recently, an increasing number of clinical trials of AAV-mediated gene therapy are underway. This review summarizes the biological functions of AAV and its application in the treatment of various ocular diseases, as well as the characteristics of different AAV delivery routes in clinical applications. Here, the latest research progresses in AAV-mediated gene editing and silencing strategies to modify that the genetic ocular diseases are systematically outlined, especially by base editing and prime editing. We discuss the progress of AAV in ocular optogenetic therapy. We also summarize the application of AAV-mediated gene therapy in animal models and the difficulties in its clinical transformation.
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Affiliation(s)
- Xiaoyu He
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yidian Fu
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Liang Ma
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Yizheng Yao
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University; Clinical Research Center of Neurological Disease,
The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Shengfang Ge
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Zhi Yang
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
| | - Xianqun Fan
- Department of Ophthalmology, Ninth People’s Hospital,
Shanghai JiaoTong University School of Medicine, Shanghai, China
- Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, China
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Solaki M, Wissinger B, Kohl S, Reuter P. Functional evaluation allows ACMG/AMP-based re-classification of CNGA3 variants associated with achromatopsia. Genet Med 2023; 25:100979. [PMID: 37689994 DOI: 10.1016/j.gim.2023.100979] [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: 04/27/2023] [Revised: 08/30/2023] [Accepted: 08/30/2023] [Indexed: 09/11/2023] Open
Abstract
PURPOSE CNGA3 encoding the main subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors is one of the major disease-associated genes for achromatopsia. Most CNGA3 variants are missense variants with the majority being functionally uncharacterized and therefore hampering genetic diagnosis. In light of potential gene therapy, objective variant pathogenicity assessment is essential. METHODS We established a medium-throughput aequorin-based luminescence bioassay allowing mutant CNGA3 channel function assessment via quantification of CNGA3 channel-mediated calcium influx in a cell culture system, thereby enabling American College of Medical Genetics and Genomics/Association for Molecular Pathology-based variant re-classification. RESULTS We provide functional read-out obtained for 150 yet uncharacterized CNGA3 missense substitutions of which 55 were previously categorized as variants of uncertain significance (VUS) identifying 25 as functionally normal and 125 as functionally abnormal. These data enabled the American College of Medical Genetics and Genomics/ Association for Molecular Pathology-based variant re-classification of 52/55 VUS as either benign, likely benign, or likely pathogenic reaching a VUS re-classification rate of 94.5%. CONCLUSION Our aequorin-based bioassay allows functionally ensured clinical variant interpretation for 150 CNGA3 missense variants enabling and supporting VUS re-classification and assuring molecular diagnosis to patients affected by CNGA3-associated achromatopsia, hereby identifying patients eligible for future gene therapy trials on this disease.
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Affiliation(s)
- Maria Solaki
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany.
| | - Peggy Reuter
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany.
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Jones MK, Orozco LD, Qin H, Truong T, Caplazi P, Elstrott J, Modrusan Z, Chaney SY, Jeanne M. Integration of human stem cell-derived in vitro systems and mouse preclinical models identifies complex pathophysiologic mechanisms in retinal dystrophy. Front Cell Dev Biol 2023; 11:1252547. [PMID: 37691820 PMCID: PMC10483287 DOI: 10.3389/fcell.2023.1252547] [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: 07/03/2023] [Accepted: 08/14/2023] [Indexed: 09/12/2023] Open
Abstract
Rare DRAM2 coding variants cause retinal dystrophy with early macular involvement via unknown mechanisms. We found that DRAM2 is ubiquitously expressed in the human eye and expression changes were observed in eyes with more common maculopathy such as Age-related Macular Degeneration (AMD). To gain insights into pathogenicity of DRAM2-related retinopathy, we used a combination of in vitro and in vivo models. We found that DRAM2 loss in human pluripotent stem cell (hPSC)-derived retinal organoids caused the presence of additional mesenchymal cells. Interestingly, Dram2 loss in mice also caused increased proliferation of cells from the choroid in vitro and exacerbated choroidal neovascular lesions in vivo. Furthermore, we observed that DRAM2 loss in human retinal pigment epithelial (RPE) cells resulted in increased susceptibility to stress-induced cell death in vitro and that Dram2 loss in mice caused age-related photoreceptor degeneration. This highlights the complexity of DRAM2 function, as its loss in choroidal cells provided a proliferative advantage, whereas its loss in post-mitotic cells, such as photoreceptor and RPE cells, increased degeneration susceptibility. Different models such as human pluripotent stem cell-derived systems and mice can be leveraged to study and model human retinal dystrophies; however, cell type and species-specific expression must be taken into account when selecting relevant systems.
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Affiliation(s)
- Melissa K. Jones
- Department of Neuroscience, Genentech Inc., South San Francisco, CA, United States
- Product Development Clinical Science Ophthalmology, Genentech Inc., South San Francisco, CA, United States
| | - Luz D. Orozco
- Department of Bioinformatics, Genentech Inc., South San Francisco, CA, United States
| | - Han Qin
- Department of Neuroscience, Genentech Inc., South San Francisco, CA, United States
| | - Tom Truong
- Department of Translational Immunology, Genentech Inc., South San Francisco, CA, United States
| | - Patrick Caplazi
- Department of Research Pathology, Genentech Inc., South San Francisco, CA, United States
| | - Justin Elstrott
- Department of Translational Imaging, Genentech Inc., South San Francisco, CA, United States
| | - Zora Modrusan
- Department of Microchemistry, Proteomics, Lipidomics and Next-Generation Sequencing, Genentech Inc., South San Francisco, CA, United States
| | - Shawnta Y. Chaney
- Department of Translational Immunology, Genentech Inc., South San Francisco, CA, United States
| | - Marion Jeanne
- Department of Neuroscience, Genentech Inc., South San Francisco, CA, United States
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Schlottmann PG, Luna JD, Labat N, Yadarola MB, Bainttein S, Esposito E, Ibañez A, Barbaro EI, Álvarez Mendiara A, Picotti CP, Chirino Misisian A, Andreussi L, Gras J, Capalbo L, Visotto M, Dipierri JE, Alcoba E, Fernández Gabrielli L, Ávila S, Aucar ME, Martin DM, Ormaechea GJ, Inga ME, Francone AA, Charles M, Zompa T, Pérez PJ, Lotersztein V, Nuova PJ, Canonero IB, Mahroo OA, Michaelides M, Arno G, Daich Varela M. Nationwide genetic analysis of more than 600 families with inherited eye diseases in Argentina. NPJ Genom Med 2023; 8:8. [PMID: 37217489 DOI: 10.1038/s41525-023-00352-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 04/05/2023] [Indexed: 05/24/2023] Open
Abstract
This study corresponds to the first large-scale genetic analysis of inherited eye diseases (IED) in Argentina and describes the comprehensive genetic profile of a large cohort of patients. Medical records of 22 ophthalmology and genetics services throughout 13 Argentinian provinces were analyzed retrospectively. Patients with a clinical diagnosis of an ophthalmic genetic disease and a history of genetic testing were included. Medical, ophthalmological and family history was collected. A total of 773 patients from 637 families were included, with 98% having inherited retinal disease. The most common phenotype was retinitis pigmentosa (RP, 62%). Causative variants were detected in 379 (59%) patients. USH2A, RPGR, and ABCA4 were the most common disease-associated genes. USH2A was the most frequent gene associated with RP, RDH12 early-onset severe retinal dystrophy, ABCA4 Stargardt disease, PROM1 cone-rod dystrophy, and BEST1 macular dystrophy. The most frequent variants were RPGR c.1345 C > T, p.(Arg449*) and USH2A c.15089 C > A, p.(Ser5030*). The study revealed 156/448 (35%) previously unreported pathogenic/likely pathogenic variants and 8 possible founder mutations. We present the genetic landscape of IED in Argentina and the largest cohort in South America. This data will serve as a reference for future genetic studies, aid diagnosis, inform counseling, and assist in addressing the largely unmet need for clinical trials to be conducted in the region.
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Affiliation(s)
| | - José D Luna
- Centro Privado de Ojos Romagosa SA, Córdoba, Argentina
| | - Natalia Labat
- Centro Privado de Ojos Romagosa SA, Córdoba, Argentina
| | | | | | - Evangelina Esposito
- University Clinic Reina Fabiola, Córdoba, Córdoba, Argentina
- Catholic University of Cordoba, Cordoba, Argentina
| | - Agustina Ibañez
- University Clinic Reina Fabiola, Córdoba, Córdoba, Argentina
- Catholic University of Cordoba, Cordoba, Argentina
| | | | | | | | | | | | | | | | - Mauro Visotto
- Instituto Oftalmológico Trelew, Trelew, Chubut, Argentina
| | | | - Emilio Alcoba
- Hospital Materno Infantil Dr Héctor Quintana, Jujuy, Argentina
| | | | - Silvia Ávila
- Facultad de Ciencias Médicas, Universidad Nacional del Comahue, Río Negro, Argentina
| | | | | | | | - M Eugenia Inga
- Organización Medica de Investigación, Buenos Aires, Argentina
| | | | | | - Tamara Zompa
- Charles Centro Oftalmológico, Buenos Aires, Argentina
| | | | | | - Pedro J Nuova
- Ocularyb Oftalmoclinica, Yerba Buena, Tucumán, Argentina
| | | | - Omar A Mahroo
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Michel Michaelides
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Gavin Arno
- Moorfields Eye Hospital, London, UK
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Malena Daich Varela
- Moorfields Eye Hospital, London, UK.
- UCL Institute of Ophthalmology, University College London, London, UK.
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Albakri A, Pisuchpen P, Capasso JE, Schneider A, Kopinsky S, Glaser T, Chiang JPW, Yomai AA, McNear D, Levin AV. Novel CRB1 pathogenic variant in Chuuk families with Leber congenital amaurosis. Am J Med Genet A 2023; 191:1007-1012. [PMID: 36595661 PMCID: PMC10262898 DOI: 10.1002/ajmg.a.63108] [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: 09/14/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 01/05/2023]
Abstract
The purpose of this article is to determine the cause of Leber congenital amaurosis (LCA) in Chuuk state, Federated States of Micronesia (FSM). In this prospective observational case series, five patients with early-onset vision loss were examined in Chuuk state, FSM, during an ocular genetics visit to study the elevated incidence of microphthalmia. Because of their low vision these patients were incorrectly assumed to have microphthalmia. A complete ophthalmological exam established a clinical diagnosis of LCA. Candidate gene exons were sequenced with a targeted retinal dystrophy panel. Five subjects in three related families were diagnosed with LCA. All five were from Tonoas Island, within the Chuuk Lagoon, with ages ranging from 6 months to 16 years. DNA sequencing of affected individuals revealed a homozygous CRB1 NM_201253.3:c.3134del pathogenic variant, which was heterozygous in their parents. CRB1 genotypes were confirmed by a PCR restriction assay. We report identification of a founder pathogenic variant in CRB1 responsible for autosomal recessive LCA in this isolated community. This discovery will lead to appropriate recurrence risk counseling.
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Affiliation(s)
- Amani Albakri
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Division of Pediatric Ophthalmology, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Phattrawan Pisuchpen
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Jenina E. Capasso
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Adele Schneider
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Division of Genetics, Einstein Healthcare Network, Philadelphia, Pennsylvania, USA
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Sarina Kopinsky
- Division of Genetics, Einstein Healthcare Network, Philadelphia, Pennsylvania, USA
| | - Tom Glaser
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, USA
| | | | | | - Donna McNear
- Independent Educational Consultant, Cambridge, Minnesota, USA
| | - Alex V. Levin
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Wei X, Li H, Wu S, Zhu T, Sui R. Genetic analysis and clinical features of three Chinese patients with Oguchi disease. Doc Ophthalmol 2023; 146:17-32. [PMID: 36417138 DOI: 10.1007/s10633-022-09910-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 10/27/2022] [Indexed: 11/24/2022]
Abstract
BACKGROUND Oguchi disease is a rare autosomal recessive form of congenital stationary night blindness caused by disease-causing variants in the rhodopsin kinase gene (GRK1) or the arrestin gene (SAG). Our study aims to describe the clinical features and identify the genetic defects for three Chinese patients with Oguchi disease. METHODS We conducted detailed ophthalmologic examinations for three patients from three unrelated non-consanguineous Chinese families. Targeted next-generation sequencing (targeted NGS) and copy number variations (CNVs) analysis were applied to screen pathogenic variants. Sanger sequencing validation, quantitative real-time PCR (qPCR), and segregation analysis were further performed for confirmation. Subsequently, a combined genetic and structural biology approach was used to infer the likely functional consequences of novel variants. RESULTS All three patients presented with typical clinical features of Oguchi disease, including night blindness, characteristic fundus appearance (Mizuo-Nakamura phenomenon), attenuated rod responses, and negative ERG waveforms. Their visual acuity and visual field were normal. Genetic analysis revealed two pathogenic variants in SAG and four pathogenic variants in GRK1. Patient 1 was identified to harbor compound heterozygous SAG variants c.874C > T (p.R292*) and exon2 deletion. Compound heterozygous GRK1 variants c.55C > T (p.R19*) and c.1412delC (p.P471Lfs*52) were found in patient 2. In patient 3, compound heterozygous GRK1 variants c.946C > A (p.R316S) and c.1388 T > C (p. L463P) were detected. CONCLUSIONS We reported the first two Chinese Oguchi patients with novel GRK1 pathogenic variants (P471Lfs*52, R316S, L463P) and one Oguchi case with SAG, indicating both GRK1 and SAG are important causative genes in Chinese Oguchi patients.
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Affiliation(s)
- Xing Wei
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, No. 1, Shuai Fu Yuan, Beijing, 100730, People's Republic of China
| | - Hui Li
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, No. 1, Shuai Fu Yuan, Beijing, 100730, People's Republic of China
| | - Shijing Wu
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, No. 1, Shuai Fu Yuan, Beijing, 100730, People's Republic of China
| | - Tian Zhu
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, No. 1, Shuai Fu Yuan, Beijing, 100730, People's Republic of China
| | - Ruifang Sui
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, No. 1, Shuai Fu Yuan, Beijing, 100730, People's Republic of China.
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Biology, Pathobiology and Gene Therapy of CNG Channel-Related Retinopathies. Biomedicines 2023; 11:biomedicines11020269. [PMID: 36830806 PMCID: PMC9953513 DOI: 10.3390/biomedicines11020269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
The visual process begins with the absorption of photons by photopigments of cone and rod photoreceptors in the retina. In this process, the signal is first amplified by a cyclic guanosine monophosphate (cGMP)-based signaling cascade and then converted into an electrical signal by cyclic nucleotide-gated (CNG) channels. CNG channels are purely ligand-gated channels whose activity can be controlled by cGMP, which induces a depolarizing Na+/Ca2+ current upon binding to the channel. Structurally, CNG channels belong to the superfamily of pore-loop cation channels and share structural similarities with hyperpolarization-activated cyclic nucleotide (HCN) and voltage-gated potassium (KCN) channels. Cone and rod photoreceptors express distinct CNG channels encoded by homologous genes. Mutations in the genes encoding the rod CNG channel (CNGA1 and CNGB1) result in retinitis-pigmentosa-type blindness. Mutations in the genes encoding the cone CNG channel (CNGA3 and CNGB3) lead to achromatopsia. Here, we review the molecular properties of CNG channels and describe their physiological and pathophysiological roles in the retina. Moreover, we summarize recent activities in the field of gene therapy aimed at developing the first gene therapies for CNG channelopathies.
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Lagman D, Haines HJ, Abalo XM, Larhammar D. Ancient multiplicity in cyclic nucleotide-gated (CNG) cation channel repertoire was reduced in the ancestor of Olfactores before re-expansion by whole genome duplications in vertebrates. PLoS One 2022; 17:e0279548. [PMID: 36584110 PMCID: PMC9803222 DOI: 10.1371/journal.pone.0279548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/09/2022] [Indexed: 12/31/2022] Open
Abstract
Cyclic nucleotide-gated (CNG) cation channels are important heterotetrameric proteins in the retina, with different subunit composition in cone and rod photoreceptor cells: three CNGA3 and one CNGB3 in cones and three CNGA1 and one CNGB1 in rods. CNGA and CNGB subunits form separate subfamilies. We have analyzed the evolution of the CNG gene family in metazoans, with special focus on vertebrates by using sequence-based phylogeny and conservation of chromosomal synteny to deduce paralogons resulting from the early vertebrate whole genome duplications (WGDs). Our analyses show, unexpectedly, that the CNGA subfamily had four sister subfamilies in the ancestor of bilaterians and cnidarians that we named CNGC, CNGD, CNGE and CNGF. Of these, CNGC, CNGE and CNGF were lost in the ancestor of Olfactores while CNGD was lost in the vertebrate ancestor. The remaining CNGA and CNGB genes were expanded by a local duplication of CNGA and the subsequent chromosome duplications in the basal vertebrate WGD events. Upon some losses, this resulted in the gnathostome ancestor having three members in the visual CNGA subfamily (CNGA1-3), a single CNGA4 gene, and two members in the CNGB subfamily (CNGB1 and CNGB3). The nature of chromosomal rearrangements in the vertebrate CNGA paralogon was resolved by including the genomes of a non-teleost actinopterygian and an elasmobranch. After the teleost-specific WGD, additional duplicates were generated and retained for CNGA1, CNGA2, CNGA3 and CNGB1. Furthermore, teleosts retain a local duplicate of CNGB3. The retention of duplicated CNG genes is explained by their subfunctionalisation and photoreceptor-specific expression. In conclusion, this study provides evidence for four previously unknown CNG subfamilies in metazoans and further evidence that the early vertebrate WGD events were instrumental in the evolution of the vertebrate visual and central nervous systems.
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Affiliation(s)
- David Lagman
- Science for Life Laboratory, Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden
- * E-mail:
| | - Helen J. Haines
- Science for Life Laboratory, Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Xesús M. Abalo
- Science for Life Laboratory, Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden
| | - Dan Larhammar
- Science for Life Laboratory, Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden
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Retinal Cyclic Nucleotide-Gated Channel Regulation by Calmodulin. Int J Mol Sci 2022; 23:ijms232214143. [PMID: 36430626 PMCID: PMC9694239 DOI: 10.3390/ijms232214143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/10/2022] [Accepted: 11/12/2022] [Indexed: 11/19/2022] Open
Abstract
Retinal cyclic nucleotide-gated (CNG) ion channels bind to intracellular cGMP and mediate visual phototransduction in photoreceptor rod and cone cells. Retinal rod CNG channels form hetero-tetramers comprised of three CNGA1 and one CNGB1 protein subunits. Cone CNG channels are similar tetramers consisting of three CNGA3 and one CNGB3 subunits. Calmodulin (CaM) binds to two distinct sites (CaM1: residues 565-587 and CaM2: residues 1120-1147) within the cytosolic domains of rod CNGB1. The binding of Ca2+-bound CaM to CNGB1 promotes the Ca2+-induced desensitization of CNG channels in retinal rods that may be important for photoreceptor light adaptation. Mutations that affect Ca2+-dependent CNG channel function are responsible for inherited forms of blindness. In this review, we propose structural models of the rod CNG channel bound to CaM that suggest how CaM might cause channel desensitization and how dysregulation of the channel may lead to retinal disease.
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Solaki M, Baumann B, Reuter P, Andreasson S, Audo I, Ayuso C, Balousha G, Benedicenti F, Birch D, Bitoun P, Blain D, Bocquet B, Branham K, Català-Mora J, De Baere E, Dollfus H, Falana M, Giorda R, Golovleva I, Gottlob I, Heckenlively JR, Jacobson SG, Jones K, Jägle H, Janecke AR, Kellner U, Liskova P, Lorenz B, Martorell-Sampol L, Messias A, Meunier I, Belga Ottoni Porto F, Papageorgiou E, Plomp AS, de Ravel TJL, Reiff CM, Renner AB, Rosenberg T, Rudolph G, Salati R, Sener EC, Sieving PA, Stanzial F, Traboulsi EI, Tsang SH, Varsanyi B, Weleber RG, Zobor D, Stingl K, Wissinger B, Kohl S. Comprehensive variant spectrum of the CNGA3 gene in patients affected by achromatopsia. Hum Mutat 2022; 43:832-858. [PMID: 35332618 DOI: 10.1002/humu.24371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 02/23/2022] [Accepted: 03/22/2022] [Indexed: 11/06/2022]
Abstract
Achromatopsia (ACHM) is a congenital cone photoreceptor disorder characterized by impaired color discrimination, low visual acuity, photosensitivity, and nystagmus. To date, six genes have been associated with ACHM (CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6), the majority of these being implicated in the cone phototransduction cascade. CNGA3 encodes the CNGA3 subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors and is one of the major disease-associated genes for ACHM. Herein, we provide a comprehensive overview of the CNGA3 variant spectrum in a cohort of 1060 genetically confirmed ACHM patients, 385 (36.3%) of these carrying "likely disease-causing" variants in CNGA3. Compiling our own genetic data with those reported in the literature and in public databases, we further extend the CNGA3 variant spectrum to a total of 316 variants, 244 of which we interpreted as "likely disease-causing" according to ACMG/AMP criteria. We report 48 novel "likely disease-causing" variants, 24 of which are missense substitutions underlining the predominant role of this mutation class in the CNGA3 variant spectrum. In addition, we provide extensive in silico analyses and summarize reported functional data of previously analyzed missense, nonsense and splicing variants to further advance the pathogenicity assessment of the identified variants.
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Affiliation(s)
- Maria Solaki
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Britta Baumann
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Peggy Reuter
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Sten Andreasson
- Department of Ophthalmology, University Hospital Lund, Lund, Sweden
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, Centre de Référence Maladies Rares REFERET, and INSERM-DGOS CIC1423, Paris, France
| | - Carmen Ayuso
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria - Fundación Jiménez Díaz University Hospital - Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Ghassan Balousha
- Department of Pathology and Histology, Faculty of Medicine, Al-Quds University, Eastern Jerusalem, Palestine
| | - Francesco Benedicenti
- Clinical Genetics Service and South Tyrol Coordination Center for Rare Diseases, Department of Pediatrics, Regional Hospital of Bolzano, Bolzano, Italy
| | - David Birch
- Retina Foundation of the Southwest, Dallas, Texas, USA
| | - Pierre Bitoun
- Genetique Medicale, CHU Paris Nord, Hopital Jean Verdier, Bondy Cedex, France
| | | | - Beatrice Bocquet
- National Reference Centre for Inherited Sensory Diseases, Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Kari Branham
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Jaume Català-Mora
- Unitat de Distròfies Hereditàries de Retina Hospital Sant Joan de Déu, Barcelona, Esplugues de Llobregat, Spain
| | - Elfride De Baere
- Department of Biomolecular Medicine, Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Helene Dollfus
- CARGO, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
- U-1112, Inserm, Faculté de Médecine, Université de Strasbourg, Strasbourg, France
| | - Mohammed Falana
- Department of Pathology and Histology, Faculty of Medicine, Al-Quds University, Eastern Jerusalem, Palestine
| | - Roberto Giorda
- Molecular Biology Laboratory, Scientific Institute IRCCS E. Medea, Bosisio Parini, Lecco, Italy
| | - Irina Golovleva
- Department of Medical Biosciences/Medical and Clinical Genetics, University of Umea, Umea, Sweden
| | - Irene Gottlob
- The University of Leicester Ulverscroft Eye Unit, Leicester Royal Infirmary, Leicester, UK
| | - John R Heckenlively
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Samuel G Jacobson
- Department of Ophthalmology, Perelman School of Medicine, Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kaylie Jones
- Retina Foundation of the Southwest, Dallas, Texas, USA
| | - Herbert Jägle
- Department of Ophthalmology, University of Regensburg, Regensburg, Germany
| | - Andreas R Janecke
- Institute of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Ulrich Kellner
- Zentrum für Seltene Netzhauterkrankungen, AugenZentrum Siegburg, MVZ Augenärztliches Diagnostik- und Therapiecentrum Siegburg GmbH, Siegburg, Germany
- RetinaScience, Bonn, 53192, Germany
| | - Petra Liskova
- Department of Paediatrics and Inherited Metabolic Disorders, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
- Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Birgit Lorenz
- Department of Ophthalmology, Justus-Liebig University Giessen, Giessen, Germany
- Department of Ophthalmology, Universitaetsklinikum Bonn, Bonn, Germany
| | | | - André Messias
- Department of Ophthalmology, Otorhinolaryngology, and Head and Neck Surgery, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Isabelle Meunier
- National Reference Centre for Inherited Sensory Diseases, Montpellier University Hospital, University of Montpellier, Montpellier, France
- Sensgene Care Network, France
| | | | - Eleni Papageorgiou
- Department of Ophthalmology, University Hospital of Larissa, Mezourlo, Larissa, Greece
| | - Astrid S Plomp
- Department of Human Genetics, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Thomy J L de Ravel
- Centre for Medical Genetics, University Hospital Brussels, Brussels, Belgium
| | | | | | - Thomas Rosenberg
- Department of Ophthalmology, National Eye Clinic, Glostrup Hospital, Glostrup, Denmark
| | - Günther Rudolph
- University Eye Hospital, Ludwig Maximilians University, Munich, Germany
| | - Roberto Salati
- Scientific Institute, IRCCS Eugenio Medea, Pediatric Ophthalmology Unit, Bosisio Parini, Lecco, Italy
| | - E Cumhur Sener
- Strabismus and Pediatric Ophthalmology, Private Practice, Ankara, Turkey
| | - Paul A Sieving
- Center for Ocular Regenerative Therapy, School of Medicine, University of California Davis, Sacramento, USA
| | - Franco Stanzial
- Clinical Genetics Service and South Tyrol Coordination Center for Rare Diseases, Department of Pediatrics, Regional Hospital of Bolzano, Bolzano, Italy
| | - Elias I Traboulsi
- Center for Genetic Eye Diseases, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Stephen H Tsang
- Department of Ophthalmology, Pathology and Cell Biology, College of Physicians and Surgeons, Columbia Stem Cell Initiative, Columbia University, New York City, New York, USA
| | - Balázs Varsanyi
- Department of Ophthalmology, Medical School, University of Pécs and Ganglion Medical Center, Pécs, Pécs, Hungary
| | - Richard G Weleber
- Oregon Health & Science University, Ophthalmic Genetics Service of the Casey Eye Institute, 515 SW Campus Drive, 97239, Portland, Oregon, USA
| | - Ditta Zobor
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Hospital Tübingen, Tübingen, Germany
- Department of Ophthalmology, Semmelweis University Budapest, Budapest, Hungary
| | - Katarina Stingl
- Center for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of Tübingen, Tübingen, Germany
| | - Bernd Wissinger
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Centre for Ophthalmology, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
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11
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Structural and functional characterization of an achromatopsia-associated mutation in a phototransduction channel. Commun Biol 2022; 5:190. [PMID: 35233102 PMCID: PMC8888761 DOI: 10.1038/s42003-022-03120-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 02/03/2022] [Indexed: 12/30/2022] Open
Abstract
Numerous missense mutations in cyclic nucleotide-gated (CNG) channels cause achromatopsia and retinitis pigmentosa, but the underlying pathogenic mechanisms are often unclear. We investigated the structural basis and molecular/cellular effects of R410W, an achromatopsia-associated, presumed loss-of-function mutation in human CNGA3. Cryo-EM structures of the Caenorhabditis elegans TAX-4 CNG channel carrying the analogous mutation, R421W, show that most apo channels are open. R421, located in the gating ring, interacts with the S4 segment in the closed state. R421W disrupts this interaction, destabilizes the closed state, and stabilizes the open state. CNGA3_R410W/CNGB3 and TAX4_R421W channels are spontaneously active without cGMP and induce cell death, suggesting cone degeneration triggered by spontaneous CNG channel activity as a possible cause of achromatopsia. Our study sheds new light on CNG channel allosteric gating, provides an impetus for a reevaluation of reported loss-of-function CNG channel missense disease mutations, and has implications for mutation-specific treatment of retinopathy. The R410W mutation in the cone photoreceptor CNG channel, linked to achromatopsia and assumed to be a loss-of-function variant, causes the channel to open spontaneously as revealed by cryo-EM, electrophysiology and calcium imaging, and is cytotoxic. This study calls for a multipronged evaluation/reevaluation of other inherited mutations associated with CNG channelopathy.
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12
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Michalakis S, Gerhardt M, Rudolph G, Priglinger S, Priglinger C. Achromatopsia: Genetics and Gene Therapy. Mol Diagn Ther 2022; 26:51-59. [PMID: 34860352 PMCID: PMC8766373 DOI: 10.1007/s40291-021-00565-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2021] [Indexed: 01/02/2023]
Abstract
Achromatopsia (ACHM), also known as rod monochromatism or total color blindness, is an autosomal recessively inherited retinal disorder that affects the cones of the retina, the type of photoreceptors responsible for high-acuity daylight vision. ACHM is caused by pathogenic variants in one of six cone photoreceptor-expressed genes. These mutations result in a functional loss and a slow progressive degeneration of cone photoreceptors. The loss of cone photoreceptor function manifests at birth or early in childhood and results in decreased visual acuity, lack of color discrimination, abnormal intolerance to light (photophobia), and rapid involuntary eye movement (nystagmus). Up to 90% of patients with ACHM carry mutations in CNGA3 or CNGB3, which are the genes encoding the alpha and beta subunits of the cone cyclic nucleotide-gated (CNG) channel, respectively. No authorized therapy for ACHM exists, but research activities have intensified over the past decade and have led to several preclinical gene therapy studies that have shown functional and morphological improvements in animal models of ACHM. These encouraging preclinical data helped advance multiple gene therapy programs for CNGA3- and CNGB3-linked ACHM into the clinical phase. Here, we provide an overview of the genetic and molecular basis of ACHM, summarize the gene therapy-related research activities, and provide an outlook for their clinical application.
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Affiliation(s)
- Stylianos Michalakis
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany.
| | - Maximilian Gerhardt
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Günther Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Siegfried Priglinger
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Claudia Priglinger
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
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13
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Shughoury A, Ciulla TA, Bakall B, Pennesi ME, Kiss S, Cunningham ET. Genes and Gene Therapy in Inherited Retinal Disease. Int Ophthalmol Clin 2021; 61:3-45. [PMID: 34584043 DOI: 10.1097/iio.0000000000000377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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14
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Tekavčič Pompe M, Vrabič N, Volk M, Meglič A, Jarc-Vidmar M, Peterlin B, Hawlina M, Fakin A. Disease Progression in CNGA3 and CNGB3 Retinopathy; Characteristics of Slovenian Cohort and Proposed OCT Staging Based on Pooled Data from 126 Patients from 7 Studies. Curr Issues Mol Biol 2021; 43:941-957. [PMID: 34449556 PMCID: PMC8929018 DOI: 10.3390/cimb43020067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 11/20/2022] Open
Abstract
Achromatopsia has been proposed to be a morphologically predominately stable retinopathy with rare reports of progression of structural changes in the macula. A five-grade system of optical coherence tomography (OCT) features has been used for the classification of structural macular changes. However, their association with age remains questionable. We characterized the Slovenian cohort of 12 patients with pathogenic variants in CNGA3 or CNGB3 who had been followed up with OCT for up to 9 years. Based on observed structural changes in association with age, the following four-stage classification of retinal morphological changes was proposed: (I) preserved inner segment ellipsoid band (Ise), (II) disrupted ISe, (III) ISe loss and (IV) ISe and RPE loss. Data from six previously published studies reporting OCT morphology in CNGA3 and CNGB3 patients were additionally collected, forming the largest CNGA3/CNGB3 cohort to date, comprising 126 patients aged 1–71 years. Multiple regression analysis showed a significant correlation of OCT stage with age (p < 0.001) and no correlation with gene (p > 0.05). The median ages of patients with stages I–IV were 12 years, 23 years, 27 years and 48 years, respectively, and no patient older than 50 years had continuous ISe. Our findings suggest that achromatopsia presents with slowly but steadily progressive structural changes of the macular outer retinal layers. However, whether morphological changes in time follow the proposed four-stage linear pattern needs to be confirmed in a long-term study.
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Affiliation(s)
- Manca Tekavčič Pompe
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
| | - Nika Vrabič
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
| | - Marija Volk
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.V.); (B.P.)
| | - Andrej Meglič
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
| | - Martina Jarc-Vidmar
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
| | - Borut Peterlin
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.V.); (B.P.)
| | - Marko Hawlina
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
| | - Ana Fakin
- Eye Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia; (M.T.P.); (N.V.); (A.M.); (M.J.-V.); (M.H.)
- Correspondence:
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15
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Kohl S, Baumann B, Dassie F, Mayer AK, Solaki M, Reuter P, Kühlewein L, Wissinger B, Maffei P. Paternal Uniparental Isodisomy of Chromosome 2 in a Patient with CNGA3-Associated Autosomal Recessive Achromatopsia. Int J Mol Sci 2021; 22:7842. [PMID: 34360608 PMCID: PMC8346044 DOI: 10.3390/ijms22157842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/13/2021] [Accepted: 07/21/2021] [Indexed: 01/18/2023] Open
Abstract
Achromatopsia (ACHM) is a rare autosomal recessively inherited retinal disease characterized by congenital photophobia, nystagmus, low visual acuity, and absence of color vision. ACHM is genetically heterogeneous and can be caused by biallelic mutations in the genes CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, or ATF6. We undertook molecular genetic analysis in a single female patient with a clinical diagnosis of ACHM and identified the homozygous variant c.778G>C;p.(D260H) in the CNGA3 gene. While segregation analysis in the father, as expected, identified the CNGA3 variant in a heterozygous state, it could not be displayed in the mother. Microsatellite marker analysis provided evidence that the homozygosity of the CNGA3 variant is due to partial or complete paternal uniparental isodisomy (UPD) of chromosome 2 in the patient. Apart from the ACHM phenotype, the patient was clinically unsuspicious and healthy. This is one of few examples proving UPD as the underlying mechanism for the clinical manifestation of a recessive mutation in a patient with inherited retinal disease. It also highlights the importance of segregation analysis in both parents of a given patient or especially in cases of homozygous recessive mutations, as UPD has significant implications for genetic counseling with a very low recurrence risk assessment in such families.
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Affiliation(s)
- Susanne Kohl
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Britta Baumann
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Francesca Dassie
- Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy; (F.D.); (P.M.)
| | - Anja K. Mayer
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Maria Solaki
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Peggy Reuter
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Laura Kühlewein
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
- Centre for Ophthalmology, University Eye Hospital, University Tübingen, 72076 Tübingen, Germany
| | - Bernd Wissinger
- Centre for Ophthalmology, Institute for Ophthalmic Research, University Tübingen, 72076 Tübingen, Germany; (B.B.); (A.K.M.); (M.S.); (P.R.); (L.K.); (B.W.)
| | - Pietro Maffei
- Department of Medicine (DIMED), University of Padua, 35121 Padua, Italy; (F.D.); (P.M.)
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16
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Brunetti-Pierri R, Karali M, Melillo P, Di Iorio V, De Benedictis A, Iaccarino G, Testa F, Banfi S, Simonelli F. Clinical and Molecular Characterization of Achromatopsia Patients: A Longitudinal Study. Int J Mol Sci 2021; 22:1681. [PMID: 33562422 PMCID: PMC7914547 DOI: 10.3390/ijms22041681] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/28/2021] [Accepted: 02/03/2021] [Indexed: 02/08/2023] Open
Abstract
Achromatopsia (ACHM) is a rare genetic disorder of infantile onset affecting cone photoreceptors. To determine the extent of progressive retinal changes in achromatopsia, we performed a detailed longitudinal phenotyping and genetic characterization of an Italian cohort comprising 21 ACHM patients (17 unrelated families). Molecular genetic testing identified biallelic pathogenic mutations in known ACHM genes, including four novel variants. At baseline, the patients presented a reduced best corrected visual acuity (BCVA), reduced macular sensitivity (MS), normal dark-adapted electroretinogram (ERG) responses and undetectable or severely reduced light-adapted ERG. The longitudinal analysis of 16 patients (mean follow-up: 5.4 ± 1.0 years) showed a significant decline of BCVA (0.012 logMAR/year) and MS (-0.16 dB/year). Light-adapted and flicker ERG responses decreased below noise level in three and two patients, respectively. Only two patients (12.5%) progressed to a worst OCT grading during the follow-up. Our findings corroborate the notion that ACHM is a progressive disease in terms of BCVA, MS and ERG responses, and affects slowly the structural integrity of the retina. These observations can serve towards the development of guidelines for patient selection and intervention timing in forthcoming gene replacement therapies.
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Affiliation(s)
- Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Marianthi Karali
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, 80078 Pozzuoli, Italy;
| | - Paolo Melillo
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Antonella De Benedictis
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Gennarfrancesco Iaccarino
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, 80078 Pozzuoli, Italy;
- Medical Genetics, Department of Precision Medicine, Università degli Studi della Campania “Luigi Vanvitelli”, via Luigi De Crecchio 7, 80138 Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania “Luigi Vanvitelli”, via Pansini 5, 80131 Naples, Italy; (R.B.-P.); (M.K.); (P.M.); (V.D.I.); (A.D.B.); (G.I.); (F.T.)
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17
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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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18
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Ross M, Ofri R, Aizenberg I, Abu-Siam M, Pe'er O, Arad D, Rosov A, Gootwine E, Dvir H, Honig H, Obolensky A, Averbukh E, Banin E, Gantz L. Naturally-occurring myopia and loss of cone function in a sheep model of achromatopsia. Sci Rep 2020; 10:19314. [PMID: 33168939 PMCID: PMC7653946 DOI: 10.1038/s41598-020-76205-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 10/23/2020] [Indexed: 01/01/2023] Open
Abstract
Achromatopsia is an inherited retinal disease characterized by loss of cone photoreceptor function. Day blind CNGA3 mutant Improved Awassi sheep provide a large animal model for achromatopsia. This study measured refractive error and axial length parameters of the eye in this model and evaluated chromatic pupillary light reflex (cPLR) testing as a potential screening test for loss of cone function. Twenty-one CNGA3 mutant, Improved Awassi, 12 control Afec-Assaf and 12 control breed-matched wild-type (WT) Awassi sheep were examined using streak retinoscopy and B-mode ocular ultrasonography. Four CNGA3 mutant and four Afec-Assaf control sheep underwent cPLR testing. Statistical tests showed that day-blind sheep are significantly more myopic than both Afec-Assaf and WT Awassi controls. Day-blind sheep had significantly longer vitreous axial length compared to WT Awassi (1.43 ± 0.13 and 1.23 ± 0.06 cm, respectively, p < 0.0002) and no response to bright red light compared to both controls. Lack of response to bright red light is consistent with cone dysfunction, demonstrating that cPLR can be used to diagnose day blindness in sheep. Day-blind sheep were found to exhibit myopia and increased vitreous chamber depth, providing a naturally occurring large animal model of myopia.
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Affiliation(s)
- Maya Ross
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
| | - Ron Ofri
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
| | - Itzhak Aizenberg
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
| | | | - Oren Pe'er
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
| | - Dikla Arad
- Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
| | - Alexander Rosov
- Institute of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Elisha Gootwine
- Institute of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Hay Dvir
- Institute of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Hen Honig
- Institute of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
| | - Alexey Obolensky
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Edward Averbukh
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Liat Gantz
- Department of Optometry and Vision Science, Hadassah Academic College, 37 Haneviim St., Jerusalem, 9101001, Israel.
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Sensing through Non-Sensing Ocular Ion Channels. Int J Mol Sci 2020; 21:ijms21186925. [PMID: 32967234 PMCID: PMC7554890 DOI: 10.3390/ijms21186925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022] Open
Abstract
Ion channels are membrane-spanning integral proteins expressed in multiple organs, including the eye. In the eye, ion channels are involved in various physiological processes, like signal transmission and visual processing. A wide range of mutations have been reported in the corresponding genes and their interacting subunit coding genes, which contribute significantly to an array of blindness, termed ocular channelopathies. These mutations result in either a loss- or gain-of channel functions affecting the structure, assembly, trafficking, and localization of channel proteins. A dominant-negative effect is caused in a few channels formed by the assembly of several subunits that exist as homo- or heteromeric proteins. Here, we review the role of different mutations in switching a “sensing” ion channel to “non-sensing,” leading to ocular channelopathies like Leber’s congenital amaurosis 16 (LCA16), cone dystrophy, congenital stationary night blindness (CSNB), achromatopsia, bestrophinopathies, retinitis pigmentosa, etc. We also discuss the various in vitro and in vivo disease models available to investigate the impact of mutations on channel properties, to dissect the disease mechanism, and understand the pathophysiology. Innovating the potential pharmacological and therapeutic approaches and their efficient delivery to the eye for reversing a “non-sensing” channel to “sensing” would be life-changing.
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Lin Q, Lv JN, Wu KC, Zhang CJ, Liu Q, Jin ZB. Generation of Nonhuman Primate Model of Cone Dysfunction through In Situ AAV-Mediated CNGB3 Ablation. Mol Ther Methods Clin Dev 2020; 18:869-879. [PMID: 32953936 PMCID: PMC7479327 DOI: 10.1016/j.omtm.2020.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/05/2020] [Indexed: 11/24/2022]
Abstract
A major challenge to the development of therapies for human retinal degenerative diseases is the lack of an ideal preclinical model because of the physiological differences between humans and most model animals. Despite the successful generation of a primate model through germline knockout of a disease-causing gene, the major issues restricting modeling in nonhuman primates (NHPs) are their relatively long lifespan, lengthy gestation, and dominant pattern of singleton births. Herein, we generated three cynomolgus macaques with macular in situ knockout by subretinal delivery of an adeno-associated virus (AAV)-mediated CRISPR-Cas9 system targeting CNGB3, the gene responsible for achromatopsia. The in vivo targeting efficiency of CRISPR-Cas9 was 12%-14%, as shown by both immunohistochemistry and single-cell transcriptomic analysis. Through clinical ophthalmic examinations, we observed a reduced response of electroretinogram in the central retina, which corresponds to a somatic disruption of CNGB3. In addition, we did not detect CRISPR-Cas9 residue in the heart, liver, spleen, kidney, brain, testis, or blood a year after administration. In conclusion, we successfully generated a NHP model of cone photoreceptor dysfunction in the central retina using an in situ CNGB3-knockout strategy.
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Affiliation(s)
- Qiang Lin
- Laboratory of Stem Cell & Retinal Regeneration, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China
| | - Ji-Neng Lv
- Laboratory of Stem Cell & Retinal Regeneration, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China
| | - Kun-Chao Wu
- Laboratory of Stem Cell & Retinal Regeneration, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China
| | - Chang-Jun Zhang
- Laboratory of Stem Cell & Retinal Regeneration, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China
| | - Qin Liu
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Boston, MA, USA
- Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Zi-Bing Jin
- Laboratory of Stem Cell & Retinal Regeneration, Division of Ophthalmic Genetics, The Eye Hospital, Wenzhou Medical University, Wenzhou 325027, China
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing 100730, China
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University & Capital Medical University, Beijing Tongren Hospital, Beijing 100730, China
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21
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Avela K, Salonen‐Kajander R, Laitinen A, Ramsden S, Barton S, Rudanko S. The genetic aetiology of retinal degeneration in children in Finland - new founder mutations identified. Acta Ophthalmol 2019; 97:805-814. [PMID: 31087526 DOI: 10.1111/aos.14128] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 04/10/2019] [Indexed: 01/22/2023]
Abstract
PURPOSE To study the genetic aetiology and phenotypes of retinal degeneration (RD) in Finnish children born during 1993-2009. METHODS Children with retinal degeneration (N = 68) were investigated during 2012-2014 with a targeted gene analysis or a next-generation sequencing (NGS) based gene panel. Also, a full clinical ophthalmological examination was performed. RESULTS The cohort covered 44% (68/153) of the Finnish children with inherited RD born 1993-2009. X-linked retinoschisis, retinitis pigmentosa, Leber congenital amaurosis and cone-rod dystrophy were the most common clinical diagnoses in the study group. Pathogenic mutations were found in 17 retinal genes. The molecular genetic aetiology was identified in 77% of the patients (in 77% of the families) analysed by NGS method. Several founder mutations were detected including three novel founder mutations c.148delG in TULP1, c.2314C>R (p.Gln772Ter) in RPGRIP1 and c.533G>A (Trp178Ter) in TYR. We also confirmed the previous tentative finding of c.2944 + 1delG in GYCU2D being the most frequent cause of Leber congenital amaurosis (LCA) in Finland. CONCLUSIONS Globally, RD is genetically heterogeneous with over 260 disease genes reported so far. This was shown not to be the case in Finland, where the genetic aetiology of RD is caused by a small group of genes, due to several founder mutations that are enriched in the population. We found that X-chromosomal retinoschisis constitutes the major group in Finnish paediatric RD population and is almost exclusively caused by two founder mutations. Several other founder mutations were detected including three novel founder mutations. All in all, the genetic aetiology of 77% of families was identified which is higher than previously reported from other populations, likely due to the specific genomic constitution of the Finns.
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Affiliation(s)
- Kristiina Avela
- The Department of Clinical Genetics Helsinki University Hospital, HUSLAB Helsinki Finland
| | | | - Arja Laitinen
- The Department of Ophthalmology Helsinki University Hospital Helsinki Finland
| | - Simon Ramsden
- St Mary′s Hospital Central Manchester University Hospitals and Manchester Centre for Genomic Medicine Manchester UK
| | - Stephanie Barton
- St Mary′s Hospital Central Manchester University Hospitals and Manchester Centre for Genomic Medicine Manchester UK
| | - Sirkka‐Liisa Rudanko
- Visio Low Vision Research Centre Finnish Federation of the Visually Impaired Helsinki Finland
- Finnish Register of Visual Impairment by National Institute for Health and Welfare Helsinki Finland
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Felden J, Baumann B, Ali M, Audo I, Ayuso C, Bocquet B, Casteels I, Garcia-Sandoval B, Jacobson SG, Jurklies B, Kellner U, Kessel L, Lorenz B, McKibbin M, Meunier I, de Ravel T, Rosenberg T, Rüther K, Vadala M, Wissinger B, Stingl K, Kohl S. Mutation spectrum and clinical investigation of achromatopsia patients with mutations in the GNAT2 gene. Hum Mutat 2019; 40:1145-1155. [PMID: 31058429 DOI: 10.1002/humu.23768] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 04/03/2019] [Accepted: 04/18/2019] [Indexed: 02/04/2023]
Abstract
Achromatopsia (ACHM) is a hereditary cone photoreceptor disorder characterized by the inability to discriminate colors, nystagmus, photophobia, and low-visual acuity. Six genes have been associated with this rare autosomal recessively inherited disease, including the GNAT2 gene encoding the catalytic α-subunit of the G-protein transducin which is expressed in the cone photoreceptor outer segment. Out of a cohort of 1,116 independent families diagnosed with a primary clinical diagnosis of ACHM, we identified 23 patients with ACHM from 19 independent families with likely causative mutations in GNAT2, representing 1.7% of our large ACHM cohort. In total 22 different potentially disease-causing variants, of which 12 are novel, were identified. The mutation spectrum also includes a novel copy number variation, a heterozygous duplication of exon 4, of which the breakpoint matches exactly that of the previously reported exon 4 deletion. Two patients carry just a single heterozygous variant. In addition to our previous study on GNAT2-ACHM, we also present detailed clinical data of these patients.
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Affiliation(s)
- Julia Felden
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Britta Baumann
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Manir Ali
- Section of Ophthalmology and Neuroscience, Leeds Institute of Medical Research at St. James's University Hospital, University of Leeds, Leeds, England
| | - Isabelle Audo
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institute de la Vision/ CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS, Paris, France
| | - Carmen Ayuso
- University Hospital Fundación Jiménez Díaz/Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Beatrice Bocquet
- Centre de Référence Maladies Sensorielles Génétiques, Hôpital Gui de Chauliac; Montpellier University and INSERM U1051, Institute for Neurosciences of Montpellier, Montpellier, France
| | - Ingele Casteels
- Department of Ophthalmology, University Hospitals Leuven, Leuven, Belgium
| | | | - Samuel G Jacobson
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | | - Ulrich Kellner
- Rare Retinal Disease Center, AugenZentrum Siegburg, MVZ ADTC Siegburg GmbH, Europaplatz 3, Siegburg, Germany
| | - Line Kessel
- The National Eye Clinic, Rigshospitalet, Kennedy Center, Glostrup, Denmark.,Department of Clinical Medicine, University of Copenhagen, Denmark
| | - Birgit Lorenz
- Department of Ophthalmology, Justus-Liebig-University Giessen, Giessen, Germany
| | - Martin McKibbin
- Section of Ophthalmology and Neuroscience, Leeds Institute of Medical Research at St. James's University Hospital, University of Leeds, Leeds, England
| | - Isabelle Meunier
- Centre de Référence Maladies Sensorielles Génétiques, Hôpital Gui de Chauliac; Montpellier University and INSERM U1051, Institute for Neurosciences of Montpellier, Montpellier, France
| | - Thomy de Ravel
- Center for Human Genetics, University Hospitals Leuven, University of Leuven, Leuven, Belgium
| | - Thomas Rosenberg
- The National Eye Clinic, Rigshospitalet, Kennedy Center, Glostrup, Denmark.,Department of Clinical Medicine, University of Copenhagen, Denmark
| | - Klaus Rüther
- Augenarztpraxis, Dorotheenstrasse 56, Berlin, Germany
| | - Maria Vadala
- Ophthalmology Institute, Dipartimento di Biomedicina, Neuroscienze e Diagnostica Avanzata (BiND), Università degli Studi di Palermo
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Katarina Stingl
- University Eye Hospital, Center for Ophthalmology, University of Tübingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
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He P, Lou X, Woody SM, He L. Amplification-by-Polymerization in Biosensing for Human Genomic DNA Detection. ACS Sens 2019; 4:992-1000. [PMID: 30942069 DOI: 10.1021/acssensors.9b00133] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A polymerization reaction was employed as a signal amplification method to realize direct visualization of gender-specific DNA extracted from human blood in a polymerase chain reaction (PCR)-free fashion. Clear distinction between X and Y chromosomes was observed by naked eyes for detector-free sensing purposes. The grown polymer films atop X and Y chromosomes were quantitatively measured by ellipsometry for thickness readings. Detection assays have been optimized for genomic DNA recognition to a maximum extent by varying the selection of the proper blocking reagents, the annealing temperature, and the annealing time. Traditional PCR and gel electrophoresis for amplicon identification were conducted in parallel for performance comparison. In the blind test for blood samples examined by the new approach, 25 out of 26 were correct and one was false negative, which was comparable to, if not better than, the PCR results. This is the first time our amplification-by-polymerization technique is being used for chromosome DNA analysis. The potential of adopting the described sensing technique without PCR was demonstrated, which could further promote the development of a portable, PCR-free DNA sensing device for point-of-need applications.
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Affiliation(s)
- Peng He
- Department of Chemistry, North Carolina Agricultural and Technical State University, Greensboro, North Carolina 27411, United States
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Xinhui Lou
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
- Department of Chemistry, Capital Normal University, Beijing 100048, China
| | - Susan M. Woody
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
- Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Lin He
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
- Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, United States
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Lee JH, Wang JH, Chen J, Li F, Edwards TL, Hewitt AW, Liu GS. Gene therapy for visual loss: Opportunities and concerns. Prog Retin Eye Res 2019; 68:31-53. [DOI: 10.1016/j.preteyeres.2018.08.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 08/23/2018] [Accepted: 08/26/2018] [Indexed: 12/17/2022]
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Hlavatá L, Ďuďáková Ľ, Moravíková J, Zobanová A, Kousal B, Lišková P. Molecular genetic cause of achromatopsia in two patients of Czech origin. CESKA A SLOVENSKA OFTALMOLOGIE : CASOPIS CESKE OFTALMOLOGICKE SPOLECNOSTI A SLOVENSKE OFTALMOLOGICKE SPOLECNOSTI 2019; 75:272-276. [PMID: 32397729 DOI: 10.31348/2019/5/5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
INTRODUCTION Achromatopsia is an autosomal recessive retinal disorder with an estimated prevalence ranging from 1 in 30.000 to 50.000. The disease is caused by mutations in six different genes. The aim of the study was to perform molecular genetic analysis in 11 unrelated probands with a clinical diagnosis of achromatopsia and to describe clinical findings in those that were found to carry biallelic pathogenic mutations. METHODS All probands and their parents underwent ophthalmic examination. Mutation detection was performed using Sanger sequencing of CNGB3 exons 6, 7, 9-13, which have been found to harbour most disease-causing mutations in patients with achromatopsia of European origin. RESULTS Three known pathogenic variants in CNGB3 were identified in 2 probands. Proband 1 was a compound heterozygote for the c.819_826del; p.(Arg274Valfs*13) and c.1006G>T; p.(Glu336*). Proband 2 carried the c.1148del; p.(Thr383Ilefs*13) in a homozygous state. The best corrected visual acuity in proband 1 (aged 19 years) was 0.1 in both eyes, in proband 2 (aged 8 years) 0.05 in the right eye and 0.1 in the left eye. Both individuals had nystagmus, photophobia, and absence of colour discrimination. Fundus examination appeared normal however spectral-domain optical coherence tomography revealed subtle bilaterally symmetrical structural changes in the fovea. CONCLUSION Molecular genetic analysis of Czech patients with achromatopsia was performed for the first time. Identification of disease-causing mutations in achromatopsia is important for establishing an early diagnosis, participation in clinical trials assessing gene therapies and may be also used for preimplantation genetic diagnosis.
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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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Sun W, Zhang Q. Diseases associated with mutations in CNGA3: Genotype-phenotype correlation and diagnostic guideline. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 161:1-27. [PMID: 30711023 DOI: 10.1016/bs.pmbts.2018.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Along with the molecular and functional characterization of CNGA3, knowledge about diseases associated with CNGA3 mutations has made great progress. So far, CNGA3 mutations are not only one of the most common causes of achromatopsia and cone dystrophy or cone-rod dystrophy but also one of the most commonly mutated genes among various forms of retinopathy. Understanding the clinical characteristics of CNGA3-associated retinal diseases may help clinical practice of infants or children with related diseases. Recognizing the importance of CNGA3 in inherited retinal diseases may enhance related research in searching for functional restoration or repair of CNGA3 defects.
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Affiliation(s)
- Wenmin Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qingjiong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
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Abdelkader E, Brandau O, Bergmann C, AlSalamah N, Nowilaty S, Schatz P. Novel causative variants in patients with achromatopsia. Ophthalmic Genet 2018; 39:678-683. [PMID: 30289319 DOI: 10.1080/13816810.2018.1522653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE To report five novel genetic variants in seven unrelated consanguineous families with achromatopsia (ACHM). METHODS Patients were examined with multimodal retinal imaging and full-field electroretinography (ffERG). Genetic testing was conducted using next-generation sequencing (NGS). RESULTS Three novel homozygous variants were detected in CNGA3: a missense c.967G > C (p.Ala323Pro) variant was detected in exon 8 (one patient), a splice site variant c.101 + 1G > A in intron 2 (three patients), and a splice site variant c.395 + 1G > T in intron 4(one patient). Another two novel variants were found in PDE6C: a homozygous missense variant c.1899C > A (p.His633Gln) in exon 15 (one patient) and a homozygous splice site variant c.1072-1G > C in intron 7 (one patient). Mutation segregation assessment was possible in 3 of the 7 families. All patients had nonrecordable ffERG 30-Hz flicker responses, reduced single-flash cone responses but preserved rod responses. Patients presented with variable degrees of foveal outer retinal layer loss and variable patterns of foveal hyperautofluorescence. CONCLUSIONS These novel variants expand the genotypes associated with ACHM and may help in future therapy development for ACHM.
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Affiliation(s)
- Ehab Abdelkader
- a Ophthalmology Department , Royal Alexandra Hospital , Paisley , UK.,b Ophthalmology Department , Menoufia University , Shebin El-Kom , Egypt
| | - Oliver Brandau
- c Bioscientia Center for Human Genetics , Ingelheim , Germany
| | | | - Nuha AlSalamah
- d King Saud University Hospital , Riyadh , Kingdom of Saudi Arabia
| | - Sawsan Nowilaty
- e King Khaled Eye Specialist Hospital , Vitreoretinal Division , Riyadh , Saudi Arabia
| | - Patrik Schatz
- e King Khaled Eye Specialist Hospital , Vitreoretinal Division , Riyadh , Saudi Arabia.,f Department of Ophthalmology, Clinical Sciences, Skane University Hospital , Lund University , Lund , Sweden
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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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30
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Weisschuh N, Stingl K, Audo I, Biskup S, Bocquet B, Branham K, Burstedt MS, De Baere E, De Vries MJ, Golovleva I, Green A, Heckenlively J, Leroy BP, Meunier I, Traboulsi E, Wissinger B, Kohl S. Mutations in the gene PDE6C encoding the catalytic subunit of the cone photoreceptor phosphodiesterase in patients with achromatopsia. Hum Mutat 2018; 39:1366-1371. [PMID: 30080950 DOI: 10.1002/humu.23606] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/24/2018] [Accepted: 08/02/2018] [Indexed: 12/22/2022]
Abstract
Biallelic PDE6C mutations are a known cause for rod monochromacy, better known as autosomal recessive achromatopsia (ACHM), and early-onset cone photoreceptor dysfunction. PDE6C encodes the catalytic α'-subunit of the cone photoreceptor phosphodiesterase, thereby constituting an essential part of the phototransduction cascade. Here, we present the results of a study comprising 176 genetically preselected patients who remained unsolved after Sanger sequencing of the most frequent genes accounting for ACHM, and were subsequently screened for exonic and splice site variants in PDE6C applying a targeted next generation sequencing approach. We were able to identify potentially pathogenic biallelic variants in 15 index cases. The mutation spectrum comprises 18 different alleles, 15 of which are novel. Our study significantly contributes to the mutation spectrum of PDE6C and allows for a realistic estimate of the prevalence of PDE6C mutations in ACHM since our entire ACHM cohort comprises 1,074 independent families.
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Affiliation(s)
- Nicole Weisschuh
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Katarina Stingl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Isabelle Audo
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France
| | - Saskia Biskup
- CeGaT GmbH and Praxis fuer Humangenetik Tuebingen, Tuebingen, Germany
| | - Béatrice Bocquet
- Institute for Neurosciences of Montpellier INSERM U1051, University of Montpellier, Montpellier, France.,National Center for Rare Genetic Retinal Dystrophies, Hopital Gui de Chauliac, Montpellier, France
| | - Kari Branham
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Marie S Burstedt
- Department of Clinical Sciences/Ophthalmology, University of Umea, Umea, Sweden
| | - Elfride De Baere
- Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Meindert J De Vries
- Department of Ophthalmology, Childrens' Hospital Queen Fabiola (Huderf), Brussels, Belgium
| | - Irina Golovleva
- Department of Medical Biosciences/Medical and Clinical Genetics, University of Umea, Umea, Sweden
| | - Andrew Green
- Department of Clinical Genetics, Our Lady's Hospital, Crumlin, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - John Heckenlively
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Bart P Leroy
- Center for Medical Genetics, Ghent University and Ghent University Hospital, Ghent, Belgium.,Ophthalmic Genetics & Visual Electrophysiology, Division of Ophthalmology & Center for Cellular & Molecular Therapy, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Ophthalmology, Ghent University Hospital & Ghent University, Ghent, Belgium
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier INSERM U1051, University of Montpellier, Montpellier, France.,National Center for Rare Genetic Retinal Dystrophies, Hopital Gui de Chauliac, Montpellier, France
| | | | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University Tuebingen, Tuebingen, Germany
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31
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Schallhorn CS, Granet DB, Ferreyra HA. ELECTRONEGATIVE ELECTRORETINOGRAM IN ACHROMATOPSIA. Retin Cases Brief Rep 2018; 12:143-148. [PMID: 27820752 DOI: 10.1097/icb.0000000000000451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To report novel electroretinographic findings in a genetically confirmed case of achromatopsia. METHODS A patient with a history of childhood nystagmus, photoaversion, and absent color vision was examined. Electroretinography and fundus examination were performed under anesthesia at the time of corrective surgery for nystagmus. Genomic DNA isolated from peripheral blood was directly sequenced for variations in the CNGA3 and CNGB3 genes. RESULTS Ophthalmoscopic examination revealed no distinct abnormalities. Electroretinography obtained under anesthesia at age three years revealed absent photopic responses. The dark-adapted combined responses had reduced b-wave amplitudes resulting in an electronegative configuration. Genetic testing revealed two heterozygous sequence variations present in the coding sequence of the CNGA3 gene (Arg223Trp and Pro372Ser), which have been previously described in the setting of achromatopsia. Sequencing of the patient's parents confirmed that these two variations lie on separate alleles. CONCLUSION Novel electroretinography findings in a patient with genetically confirmed achromatopsia are reported. The electronegative configuration in this clinical setting is of unclear etiology; however, it may suggest some component of inner retinal dysfunction.
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Affiliation(s)
| | - David B Granet
- UC San Diego Health System, Shiley Eye Institute, La Jolla, California
| | - Henry A Ferreyra
- UC San Diego Health System, Shiley Eye Institute, La Jolla, California
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32
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Abstract
The first step in vision is the absorption of photons by the photopigments in cone and rod photoreceptors. After initial amplification within the phototransduction cascade the signal is translated into an electrical signal by the action of cyclic nucleotide-gated (CNG) channels. CNG channels are ligand-gated ion channels that are activated by the binding of cyclic guanosine monophosphate (cGMP) or cyclic adenosine monophosphate (cAMP). Retinal CNG channels transduce changes in intracellular concentrations of cGMP into changes of the membrane potential and the Ca2+ concentration. Structurally, the CNG channels belong to the superfamily of pore-loop cation channels and share a common gross structure with hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and voltage-gated potassium channels (KCN). In this review, we provide an overview on the molecular properties of CNG channels and describe their physiological role in the phototransduction pathways. We also discuss insights into the pathophysiological role of CNG channel proteins that have emerged from the analysis of CNG channel-deficient animal models and human CNG channelopathies. Finally, we summarize recent gene therapy activities and provide an outlook for future clinical application.
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Affiliation(s)
- Stylianos Michalakis
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
| | - Elvir Becirovic
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
| | - Martin Biel
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
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33
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Edwards TL. Discovery of Māori and Polynesian phototransduction pathway founder mutation: what is the gene and what does it mean? Clin Exp Ophthalmol 2017; 45:854-856. [PMID: 29271598 DOI: 10.1111/ceo.13080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas L Edwards
- Centre for Eye Research Australia, Melbourne, Victoria, Australia.,Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Nuffield Laboratory of Ophthalmology, University of Oxford, Oxford, UK
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34
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Bertsch M, Floyd M, Kehoe T, Pfeifer W, Drack AV. The clinical evaluation of infantile nystagmus: What to do first and why. Ophthalmic Genet 2017; 38:22-33. [PMID: 28177849 DOI: 10.1080/13816810.2016.1266667] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Infantile nystagmus has many causes, some life threatening. We determined the most common diagnoses in order to develop a testing algorithm. METHODS Retrospective chart review. Exclusion criteria were no nystagmus, acquired after 6 months, or lack of examination. DATA COLLECTED pediatric eye examination findings, ancillary testing, order of testing, referral, and final diagnoses. Final diagnosis was defined as meeting published clinical criteria and/or confirmed by diagnostic testing. Patients with a diagnosis not meeting the definition were "unknown." Patients with incomplete testing were "incomplete." Patients with multiple plausible etiologies were "multifactorial." Patients with negative complete workup were "motor." RESULTS A total of 284 charts were identified; 202 met inclusion criteria. The three most common causes were Albinism (19%), Leber Congenital Amaurosis (LCA; 14%), and Non-LCA retinal dystrophy (13%). Anatomic retinal disorders comprised 10%, motor another 10%. The most common first test was MRI (74/202) with a diagnostic yield of 16%. For 28 MRI-first patients, nystagmus alone was the indication; for 46 MRI-first patients other neurologic signs were present. 0/28 nystagmus-only patients had a diagnostic MRI while 14/46 (30%) with neurologic signs did. The yield of ERG as first test was 56%, OCT 55%, and molecular genetic testing 47%. Overall, 90% of patients had an etiology identified. CONCLUSION The most common causes of infantile nystagmus were retinal disorders (56%), however the most common first test was brain MRI. For patients without other neurologic stigmata complete pediatric eye examination, ERG, OCT, and molecular genetic testing had a higher yield than MRI scan. If MRI is not diagnostic, a complete ophthalmologic workup should be pursued.
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Affiliation(s)
- Morgan Bertsch
- a Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research , Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City , Iowa , USA
| | - Michael Floyd
- a Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research , Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City , Iowa , USA.,b HealthPartners , Minneapolis , Minnesota , USA
| | - Taylor Kehoe
- a Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research , Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City , Iowa , USA.,c Physician Assistant Program , University of Iowa , Iowa City , Iowa , USA
| | - Wanda Pfeifer
- a Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research , Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City , Iowa , USA
| | - Arlene V Drack
- a Department of Ophthalmology and Visual Sciences, Wynn Institute for Vision Research , Roy J. and Lucille A. Carver College of Medicine, University of Iowa , Iowa City , Iowa , USA
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35
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Di Iorio V, Karali M, Brunetti-Pierri R, Filippelli M, Di Fruscio G, Pizzo M, Mutarelli M, Nigro V, Testa F, Banfi S, Simonelli F. Clinical and Genetic Evaluation of a Cohort of Pediatric Patients with Severe Inherited Retinal Dystrophies. Genes (Basel) 2017; 8:genes8100280. [PMID: 29053603 PMCID: PMC5664130 DOI: 10.3390/genes8100280] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/02/2017] [Accepted: 10/13/2017] [Indexed: 12/30/2022] Open
Abstract
We performed a clinical and genetic characterization of a pediatric cohort of patients with inherited retinal dystrophy (IRD) to identify the most suitable cases for gene therapy. The cohort comprised 43 patients, aged between 2 and 18 years, with severe isolated IRD at the time of presentation. The ophthalmological characterization also included assessment of the photoreceptor layer integrity in the macular region (ellipsoid zone (EZ) band). In parallel, we carried out a targeted, next-generation sequencing (NGS)-based analysis using a panel that covers over 150 genes with either an established or a candidate role in IRD pathogenesis. Based on the ophthalmological assessment, the cohort was composed of 24 Leber congenital amaurosis, 14 early onset retinitis pigmentosa, and 5 achromatopsia patients. We identified causative mutations in 58.1% of the cases. We also found novel genotype-phenotype correlations in patients harboring mutations in the CEP290 and CNGB3 genes. The EZ band was detectable in 40% of the analyzed cases, also in patients with genotypes usually associated with severe clinical manifestations. This study provides the first detailed clinical-genetic assessment of severe IRDs with infantile onset and lays the foundation of a standardized protocol for the selection of patients that are more likely to benefit from gene replacement therapeutic approaches.
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Affiliation(s)
- Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Marianthi Karali
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Mariaelena Filippelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Giuseppina Di Fruscio
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
| | - Mariateresa Pizzo
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Margherita Mutarelli
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Vincenzo Nigro
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Sandro Banfi
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
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36
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Banerjee S, Yao J, Zhang X, Niu J, Chen Z. Next generation sequencing identified novel heterozygous nonsense mutation in CNGB1 gene associated with retinitis pigmentosa in a Chinese patient. Oncotarget 2017; 8:88345-88350. [PMID: 29179439 PMCID: PMC5687609 DOI: 10.18632/oncotarget.21728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 09/08/2017] [Indexed: 11/25/2022] Open
Abstract
Retinitis pigmentosa (RP) is a severe hereditary eye disease characterized by progressive degeneration of photoreceptors and subsequent loss of vision. Retinitis pigmentosa (RP) is a clinically and genetically heterogeneous group of retinal diseases. Germline mutations of CNGB1 is associated with retinitis pigmentosa. We have identified and investigated a 34-year-old Chinese man with markedly have night vision blindness and loss of midperipheral visual field. The proband also lose his far peripheral visual field and also central vision. Proband's retinal pigment deposits visible on fundus examination and primary loss of rod photoreceptor cells followed by secondary loss of cone photoreceptors. Target exome capture based next generation sequencing and Sanger sequencing identified novel nonsense mutation, c.1917G>A and a reported mutation, c.2361C>A, in the CNGB1 gene. Both the nonsense mutations are predicted to lead to the formation of a premature stop codon which finally results into formation of truncated CNGB1 protein product which finally predicted to be disease causing. According to the variant classification guidelines of ACMG, these two variants are categorized as "likely pathogenic" variants. Our findings expand the mutational spectra of CNGB1 and are valuable in the mutation-based pre- and post-natal screening and genetic diagnosis for retinitis pigmentosa.
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Affiliation(s)
- Santasree Banerjee
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Junping Yao
- Department of Ophthalmology, Tianyou Hospital Affiliated to Wuhan University of Science & Technology, Wuhan, China
| | - Xinxin Zhang
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jianjun Niu
- Department of Ophthalmology, General Hospital of Xinjiang Military Area Command of Chinese PLA, Urumqi, China
| | - Zhongshan Chen
- Department of Ophthalmology, Zhongnan Hospital of Wuhan University, Wuhan, China
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37
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Maguire J, McKibbin M, Khan K, Kohl S, Ali M, McKeefry D. CNGB3 mutations cause severe rod dysfunction. Ophthalmic Genet 2017; 39:108-114. [PMID: 28929832 DOI: 10.1080/13816810.2017.1368087] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE Congenital achromatopsia or rod monochromatism is a rare autosomal recessive condition defined by a severe loss of cone photoreceptor function in which rods purportedly retain normal or near-to-normal function. This report describes the results of electroretinography in two siblings with CNGB3-associated achromatopsia. METHODS Full field light- and dark-adapted electroretinograms (ERGs) were recorded using standard protocols detailed by the International Society for Clinical Electrophysiology of Vision (ISCEV). We also examined rod-mediated ERGs using series of stimuli that varied over a 6 log unit range of retinal illuminances (-1.9-3.5 log scotopic trolands). RESULTS Dark-adapted ERGs in achromatopsia patients exhibited severely reduced b-wave amplitudes with abnormal b:a ratios (1.3 and 0.6). In comparison, the reduction in a-wave amplitude was less marked. The rod-mediated ERG took on an electronegative appearance at high-stimulus illuminances. CONCLUSION Although the defect that causes achromatopsia is primarily in the cone photoreceptors, our results reveal an accompanying disruption of rod function that is more severe than has previously been reported. The differential effects on the b-wave relative to the a-wave points to an inner-retinal locus for the disruption of rod function in these patients.
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Affiliation(s)
- J Maguire
- a School of Optometry and Vision Sciences , University of Bradford , Bradford , West Yorkshire , UK
| | - M McKibbin
- b Department of Ophthalmology , St. James's University Teaching Hospital , Leeds , UK
| | - K Khan
- b Department of Ophthalmology , St. James's University Teaching Hospital , Leeds , UK
| | - S Kohl
- c Molecular Genetics Laboratory, Institute of Ophthalmic Research, Centre of Ophthalmology , University Clinics Tubingen , Tubingen , Germany
| | - M Ali
- d Section of Ophthalmology and Neuroscience, Leeds Institute of Biomedical and Clinical Sciences , University of Leeds , Leeds , UK
| | - D McKeefry
- a School of Optometry and Vision Sciences , University of Bradford , Bradford , West Yorkshire , UK
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38
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Mayer AK, Van Cauwenbergh C, Rother C, Baumann B, Reuter P, De Baere E, Wissinger B, Kohl S. CNGB3 mutation spectrum including copy number variations in 552 achromatopsia patients. Hum Mutat 2017; 38:1579-1591. [PMID: 28795510 DOI: 10.1002/humu.23311] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/25/2017] [Accepted: 08/04/2017] [Indexed: 02/03/2023]
Abstract
Achromatopsia is a rare autosomal recessive cone disorder characterized by color vision defects, photophobia, nystagmus, and severely reduced visual acuity. The disease is caused by mutations in genes encoding crucial components of the cone phototransduction cascade (CNGA3, CNGB3, GNAT2, PDE6C, and PDE6H) or in ATF6, involved in the unfolded protein response. CNGB3 encoding the beta subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors is the major achromatopsia gene. Here, we present a comprehensive spectrum of CNGB3 mutations and their prevalence in a cohort of 1074 independent families clinically diagnosed with achromatopsia. Of these, 485 (45.2%) carried mutations in CNGB3. We identified a total of 98 different potentially disease-causing CNGB3 variants, 58 of which are novel. About 10% of patients with CNGB3 mutations only harbored a single heterozygous variant. Therefore, we performed quantitative real-time PCR in 43 of such single heterozygotes in search of the missing allele, followed by microarray-based comparative genomic hybridization and breakpoint mapping. We discovered nine different heterozygous copy number variations encompassing one to 10 consecutive exons in 16 unrelated patients. Moreover, one additional patient with a homozygous CNGB3 deletion encompassing exons 4-18 was identified, highlighting the importance of CNV analysis for this gene.
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Affiliation(s)
- Anja K Mayer
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
| | - Caroline Van Cauwenbergh
- Department of Ophthalmology, Ghent University and Ghent University Hospital, Ghent, Belgium.,Center for Medical Genetics Ghent, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Christine Rother
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
| | - Britta Baumann
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
| | - Peggy Reuter
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
| | - Elfride De Baere
- Center for Medical Genetics Ghent, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany
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Wang X, Zein WM, D'Souza L, Roberson C, Wetherby K, He H, Villarta A, Turriff A, Johnson KR, Fann YC. Applying next generation sequencing with microdroplet PCR to determine the disease-causing mutations in retinal dystrophies. BMC Ophthalmol 2017; 17:157. [PMID: 28838317 PMCID: PMC5571584 DOI: 10.1186/s12886-017-0549-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 08/14/2017] [Indexed: 01/07/2023] Open
Abstract
Background Inherited Retinal dystrophy (IRD) is a broad group of inherited retinal disorders with heterogeneous genotypes and phenotypes. Next generation sequencing (NGS) methods have been broadly applied for analyzing patients with IRD. Here we report a novel approach to enrich the target gene panel by microdroplet PCR. Methods This assay involved a primer library which targeted 3071 amplicons from 2078 exons comprised of 184 genes involved in retinal function and/or retinal development. We amplified the target regions using the RainDance target enrichment PCR method and sequenced the products using the MiSeq NGS platform. Results In this study, we analyzed 82 samples from 67 families with IRD. Bioinformatics analysis indicated that this procedure was able to reach 99% coverage of target sequences with an average sequence depth of reads at 119×. The variants detected by this study were filtered, validated, and prioritized by pathogenicity analysis. Genotypes and phenotypes were correlated by determining a consistent relationship in 38 propands (56.7%). Pathogenic variants in genes related to retinal function were found in another 11 probands (16.4%), but the clinical correlations showed inconsistencies and insufficiencies in these patients. Conclusions The application of NGS in IRD clinical molecular diagnosis provides a powerful approach to exploring the etiology and pathology in patients. It is important for the clinical laboratory to interpret the molecular findings in the context of patient clinical presentations because accurate interpretation of pathogenic variants is critical for delivering solid clinical molecular diagnosis to clinicians and patients and improving the standard care of patients. Electronic supplementary material The online version of this article (doi:10.1186/s12886-017-0549-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xinjing Wang
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA.
| | - Wadih M Zein
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Leera D'Souza
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Chimere Roberson
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Keith Wetherby
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Hong He
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Angela Villarta
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Amy Turriff
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, 10D43, 10 Center Drive, Bethesda, MD, 20892, USA
| | - Kory R Johnson
- Intramural IT and Bioinformatics Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Yang C Fann
- Intramural IT and Bioinformatics Program, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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Aboshiha J, Kumaran N, Kalitzeos A, Hogg C, Rubin G, Michaelides M. A Quantitative and Qualitative Exploration of Photoaversion in Achromatopsia. Invest Ophthalmol Vis Sci 2017; 58:3537-3546. [PMID: 28715587 PMCID: PMC5510991 DOI: 10.1167/iovs.17-21935] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Photoaversion (PA) is a disabling and ubiquitous feature of achromatopsia (ACHM). We aimed to help define the characteristics of this important symptom, and present the first published assessment of its impact on patients' lives, as well as quantitative and qualitative PA assessments. Methods Molecularly confirmed ACHM subjects were assessed for PA using four tasks: structured survey of patient experience, novel quantitative subjective measurement of PA, visual acuities in differing ambient lighting, and objective palpebral aperture-related PA testing. Results Photoaversion in ACHM was found to be the most significant symptom for a substantial proportion (38%) of patients. A novel subjective PA measurement technique was developed and demonstrated fidelity with more invasive paradigms without exposing often very photosensitive patients to brighter light intensities used elsewhere. An objective PA measurement was also refined for use in trials, indicating that higher light intensities than previously published are likely to be needed. Monocular testing, as required for trials, was also validated for the first time. Conclusions This study offers new insights into PA in ACHM. It provides the first structured evidence of the great significance of this symptom to patients, suggesting that PA should be considered as an additional outcome measure in therapeutic trials. It also offers new insights into the characteristics of PA in ACHM, and describes both subjective and objective measures of PA that could be employed in clinical trials.
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Affiliation(s)
- Jonathan Aboshiha
- UCL Institute of Ophthalmology, University College London, London, United Kingdom 2Moorfields Eye Hospital, London, United Kingdom
| | - Neruban Kumaran
- UCL Institute of Ophthalmology, University College London, London, United Kingdom 2Moorfields Eye Hospital, London, United Kingdom
| | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, University College London, London, United Kingdom 2Moorfields Eye Hospital, London, United Kingdom
| | - Chris Hogg
- Moorfields Eye Hospital, London, United Kingdom
| | - Gary Rubin
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom 2Moorfields Eye Hospital, London, United Kingdom
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Mühlfriedel R, Tanimoto N, Schön C, Sothilingam V, Garcia Garrido M, Beck SC, Huber G, Biel M, Seeliger MW, Michalakis S. AAV-Mediated Gene Supplementation Therapy in Achromatopsia Type 2: Preclinical Data on Therapeutic Time Window and Long-Term Effects. Front Neurosci 2017; 11:292. [PMID: 28596720 PMCID: PMC5442229 DOI: 10.3389/fnins.2017.00292] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/08/2017] [Indexed: 11/13/2022] Open
Abstract
Achromatopsia type 2 (ACHM2) is a severe, inherited eye disease caused by mutations in the CNGA3 gene encoding the α subunit of the cone photoreceptor cyclic nucleotide-gated (CNG) channel. Patients suffer from strongly impaired daylight vision, photophobia, nystagmus, and lack of color discrimination. We have previously shown in the Cnga3 knockout (KO) mouse model of ACHM2 that gene supplementation therapy is effective in rescuing cone function and morphology and delaying cone degeneration. In our preclinical approach, we use recombinant adeno-associated virus (AAV) vector-mediated gene transfer to express the murine Cnga3 gene under control of the mouse blue opsin promoter. Here, we provide novel data on the efficiency and permanence of such gene supplementation therapy in Cnga3 KO mice. Specifically, we compare the influence of two different AAV vector capsids, AAV2/5 (Y719F) and AAV2/8 (Y733F), on restoration of cone function, and assess the effect of age at time of treatment on the long-term outcome. The evaluation included in vivo analysis of retinal function using electroretinography (ERG) and immunohistochemical analysis of vector-driven Cnga3 transgene expression. We found that both vector capsid serotypes led to a comparable rescue of cone function over the observation period between 4 weeks and 3 months post treatment. In addition, a clear therapeutic effect was present in mice treated at 2 weeks of age as well as in mice treated at 3 months of age at the first assessment at 4 weeks after treatment. Importantly, the effect extended in both cases over the entire observation period of 12 months post treatment. However, the average ERG amplitude levels differed between the two groups, suggesting a role of the absolute age, or possibly, the associated state of the degeneration, on the achievable outcome. In summary, we found that the therapeutic time window of opportunity for AAV-mediated Cnga3 gene supplementation therapy in the Cnga3 KO mouse model extends at least to an age of 3 months, but is presumably limited by the condition, number and topographical distribution of remaining cones at the time of treatment. No impact of the choice of capsid on the therapeutic success was detected.
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Affiliation(s)
- Regine Mühlfriedel
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Naoyuki Tanimoto
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Christian Schön
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Vithiyanjali Sothilingam
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Marina Garcia Garrido
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Susanne C Beck
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Gesine Huber
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Martin Biel
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität MünchenMunich, Germany
| | - Mathias W Seeliger
- Division of Ocular Neurodegeneration, Centre for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls-Universität TübingenTuebingen, Germany
| | - Stylianos Michalakis
- Department of Pharmacy, Center for Drug Research, Center for Integrated Protein Science Munich, Ludwig-Maximilians-Universität MünchenMunich, Germany
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Li L, Chen Y, Jiao X, Jin C, Jiang D, Tanwar M, Ma Z, Huang L, Ma X, Sun W, Chen J, Ma Y, M'hamdi O, Govindarajan G, Cabrera PE, Li J, Gupta N, Naeem MA, Khan SN, Riazuddin S, Akram J, Ayyagari R, Sieving PA, Riazuddin SA, Hejtmancik JF. Homozygosity Mapping and Genetic Analysis of Autosomal Recessive Retinal Dystrophies in 144 Consanguineous Pakistani Families. Invest Ophthalmol Vis Sci 2017; 58:2218-2238. [PMID: 28418496 PMCID: PMC5397137 DOI: 10.1167/iovs.17-21424] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Purpose The Pakistan Punjab population has been a rich source for identifying genes causing or contributing to autosomal recessive retinal degenerations (arRD). This study was carried out to delineate the genetic architecture of arRD in the Pakistani population. Methods The genetic origin of arRD in a total of 144 families selected only for having consanguineous marriages and multiple members affected with arRD was examined. Of these, causative mutations had been identified in 62 families while only the locus had been identified for an additional 15. The remaining 67 families were subjected to homozygosity exclusion mapping by screening of closely flanking microsatellite markers at 180 known candidate genes/loci followed by sequencing of the candidate gene for pathogenic changes. Results Of these 67 families subjected to homozygosity mapping, 38 showed homozygosity for at least one of the 180 regions, and sequencing of the corresponding genes showed homozygous cosegregating mutations in 27 families. Overall, mutations were detected in approximately 61.8 % (89/144) of arRD families tested, with another 10.4% (15/144) being mapped to a locus but without a gene identified. Conclusions These results suggest the involvement of unmapped novel genes in the remaining 27.8% (40/144) of families. In addition, this study demonstrates that homozygosity mapping remains a powerful tool for identifying the genetic defect underlying genetically heterogeneous arRD disorders in consanguineous marriages for both research and clinical applications.
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Affiliation(s)
- Lin Li
- Department of Ophthalmology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China 2Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Yabin Chen
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Xiaodong Jiao
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Chongfei Jin
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 3Department of Medicine, Brookdale University Hospital and Medical Center, New York, New York, United States
| | - Dan Jiang
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Mukesh Tanwar
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 4Department of Genetics, Maharshi Dayanand University Rohtak, Haryana, India
| | - Zhiwei Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Li Huang
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 5State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xiaoyin Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 6Laboratory of Developmental Cell Biology and Disease, School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Wenmin Sun
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 5State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jianjun Chen
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 7Department of Ophthalmology, Shanghai Tenth People's Hospital, and Tongji Eye Institute, Tongji University School of Medicine, Shanghai, China
| | - Yan Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Oussama M'hamdi
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Gowthaman Govindarajan
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Patricia E Cabrera
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Jiali Li
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States 5State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Nikhil Gupta
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - Muhammad Asif Naeem
- National Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Shaheen N Khan
- National Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Sheikh Riazuddin
- National Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan 9Allama Iqbal Medical College, University of Health Sciences, Lahore, Pakistan 10National Centre for Genetic Diseases, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Javed Akram
- Allama Iqbal Medical College, University of Health Sciences, Lahore, Pakistan 10National Centre for Genetic Diseases, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad, Pakistan
| | - Radha Ayyagari
- Shiley Eye Institute, University of California-San Diego, La Jolla, California, United States
| | - Paul A Sieving
- National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
| | - S Amer Riazuddin
- The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States 14McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, United States
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Differences in ocular findings in two siblings: one with complete and other with incomplete achromatopsia. Doc Ophthalmol 2017; 134:141-147. [DOI: 10.1007/s10633-017-9577-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 02/09/2017] [Indexed: 10/20/2022]
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Whole exome sequencing using Ion Proton system enables reliable genetic diagnosis of inherited retinal dystrophies. Sci Rep 2017; 7:42078. [PMID: 28181551 PMCID: PMC5299602 DOI: 10.1038/srep42078] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/05/2017] [Indexed: 01/17/2023] Open
Abstract
Inherited retinal dystrophies (IRD) comprise a wide group of clinically and genetically complex diseases that progressively affect the retina. Over recent years, the development of next-generation sequencing (NGS) methods has transformed our ability to diagnose heterogeneous diseases. In this work, we have evaluated the implementation of whole exome sequencing (WES) for the molecular diagnosis of IRD. Using Ion ProtonTM system, we simultaneously analyzed 212 genes that are responsible for more than 25 syndromic and non-syndromic IRD. This approach was used to evaluate 59 unrelated families, with the pathogenic variant(s) successfully identified in 71.18% of cases. Interestingly, the mutation detection rate varied substantially depending on the IRD subtype. Overall, we found 63 different mutations (21 novel) in 29 distinct genes, and performed in vivo functional studies to determine the deleterious impact of variants identified in MERTK, CDH23, and RPGRIP1. In addition, we provide evidences that support CDHR1 as a gene responsible for autosomal recessive retinitis pigmentosa with early macular affectation, and present data regarding the disease mechanism of this gene. Altogether, these results demonstrate that targeted WES of all IRD genes is a reliable, hypothesis-free approach, and a cost- and time-effective strategy for the routine genetic diagnosis of retinal dystrophies.
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Ueno S, Nakanishi A, Kominami T, Ito Y, Hayashi T, Yoshitake K, Kawamura Y, Tsunoda K, Iwata T, Terasaki H. In vivo imaging of a cone mosaic in a patient with achromatopsia associated with a GNAT2 variant. Jpn J Ophthalmol 2017; 61:92-98. [PMID: 27718025 DOI: 10.1007/s10384-016-0484-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Accepted: 08/30/2016] [Indexed: 11/26/2022]
Abstract
PURPOSE The 2 most common causative genes for achromatopsia (ACHM) are CNGA3 and CNGB3; other genes including GNAT2 account for only a small portion of ACHM cases. The cone mosaics in eyes with CNGA3 and CNGB3 variants are severely disrupted; the cone mosaics in patients with GNAT2-associated ACHM; however, have been reported to show a contiguous pattern in adaptive optics (AO) retinal images. The purpose of this study was to analyze the cone mosaic of another case of GNAT2-associated ACHM. PATIENT AND METHODS The patient was a 17-year-old Japanese boy. Comprehensive ocular examinations including fundus photography, electroretinography (ERGs), optical coherence tomography (OCT), and whole-exome analysis were performed. The cone mosaic was recorded with a flood-illuminated AO fundus camera, and the cone density was compared with those of 10 normal control eyes. RESULTS The patient had the typical phenotype of ACHM, and a novel homozygous variant, c.730_743del, in GNAT2 was identified. The fundus did not show any specific abnormalities, and the OCT images showed the presence of the ellipsoid zone. The AO fundus image showed a clearly defined cone mosaic around the fovea. The cone density at 500 μm from the fovea was reduced by 15-30 % as compared with those of the normal eyes. CONCLUSIONS This is the first description of a Japanese patient with ACHM with a novel GNAT2 variant. The eyes of this patient had a preserved cone structure with loss of function.
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Affiliation(s)
- Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan.
| | - Ayami Nakanishi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Taro Kominami
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Yasuki Ito
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Kazutoshi Yoshitake
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Yuichi Kawamura
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Kazushige Tsunoda
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Takeshi Iwata
- National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Nagoya, 466-8550, Japan
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de Castro-Miró M, Tonda R, Escudero-Ferruz P, Andrés R, Mayor-Lorenzo A, Castro J, Ciccioli M, Hidalgo DA, Rodríguez-Ezcurra JJ, Farrando J, Pérez-Santonja JJ, Cormand B, Marfany G, Gonzàlez-Duarte R. Novel Candidate Genes and a Wide Spectrum of Structural and Point Mutations Responsible for Inherited Retinal Dystrophies Revealed by Exome Sequencing. PLoS One 2016; 11:e0168966. [PMID: 28005958 PMCID: PMC5179108 DOI: 10.1371/journal.pone.0168966] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 12/09/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND NGS-based genetic diagnosis has completely revolutionized the human genetics field. In this study, we have aimed to identify new genes and mutations by Whole Exome Sequencing (WES) responsible for inherited retinal dystrophies (IRD). METHODS A cohort of 33 pedigrees affected with a variety of retinal disorders was analysed by WES. Initial prioritization analysis included around 300 IRD-associated genes. In non-diagnosed families a search for pathogenic mutations in novel genes was undertaken. RESULTS Genetic diagnosis was attained in 18 families. Moreover, a plausible candidate is proposed for 10 more cases. Two thirds of the mutations were novel, including 4 chromosomal rearrangements, which expand the IRD allelic heterogeneity and highlight the contribution of private mutations. Our results prompted clinical re-evaluation of some patients resulting in assignment to a syndromic instead of non-syndromic IRD. Notably, WES unveiled four new candidates for non-syndromic IRD: SEMA6B, CEP78, CEP250, SCLT1, the two latter previously associated to syndromic disorders. We provide functional data supporting that missense mutations in CEP250 alter cilia formation. CONCLUSION The diagnostic efficiency of WES, and strictly following the ACMG/AMP criteria is 55% in reported causative genes or functionally supported new candidates, plus 30% families in which likely pathogenic or VGUS/VUS variants were identified in plausible candidates. Our results highlight the clinical utility of WES for molecular diagnosis of IRD, provide a wider spectrum of mutations and concomitant genetic variants, and challenge our view on syndromic vs non-syndromic, and causative vs modifier genes.
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Affiliation(s)
- Marta de Castro-Miró
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Raul Tonda
- CNAG-CRG, Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Paula Escudero-Ferruz
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
| | - Rosa Andrés
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
| | | | - Joaquín Castro
- Servicio de Oftalmología, Unidad de Retina, Hospital Universitario Central de Asturias, Oviedo, Spain
| | | | - Daniel A. Hidalgo
- Hospital Interzonal General de Agudos Eva Perón, Buenos Aires, Argentina
| | | | - Jorge Farrando
- Institut Oftalmològic Quirón Barcelona, Barcelona, Spain
| | - Juan J. Pérez-Santonja
- Department of Ophthalmology, Alicante University General Hospital, Alicante Institute for Health and Biomedical Research (ISABIAL-FISABIO Foundation), Alicante, Spain
| | - Bru Cormand
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Gemma Marfany
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Roser Gonzàlez-Duarte
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
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Kuniyoshi K, Muraki-Oda S, Ueyama H, Toyoda F, Sakuramoto H, Ogita H, Irifune M, Yamamoto S, Nakao A, Tsunoda K, Iwata T, Ohji M, Shimomura Y. Novel mutations in the gene for α-subunit of retinal cone cyclic nucleotide-gated channels in a Japanese patient with congenital achromatopsia. Jpn J Ophthalmol 2016; 60:187-97. [PMID: 27040408 DOI: 10.1007/s10384-016-0424-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
Abstract
PURPOSE To present the characteristics and pathology of a patient with congenital achromatopsia. PATIENT AND METHODS The patient was a 22-year-old Japanese woman who was 8 years old when she first visited our clinic. Comprehensive ophthalmic examinations including visual acuity measurements, perimetry, optical coherence tomography (OCT), fundus autofluorescence (FAF) imaging, electroretinography (ERG), and color vision tests were performed. Her genomic DNA was used as the template for the amplification of exons of five candidate genes for achromatopsia; CNGA3, CNGB3, GNAT2, PDE6C, and PDE6H, and the amplified products were sequenced. A missense mutation, found in the CNGA3, was studied both electrophysiologically and biochemically. RESULTS Her phenotype was typical of congenital complete achromatopsia. She was followed for 14 years, and her vision and fundus findings were stable. However, the scotopic ERG b-waves at age 22 were smaller than those at age 8, and her FAF images showed increased autofluorescence in both maculae. Genetic examinations revealed combined heterozygous mutations of c.997_998delGA and p.M424V in the CNGA3 gene. The homomeric channel consisting of the CNGA3 subunit with the p.M424V mutation had a weak cGMP-activated current in patch-clamp recordings. In heterologous expression analyses, the expression at the cell surface of the mutant CNGA3 subunit was about 28 % of the wild type. CONCLUSIONS The two novel mutations found in the CNGA3 gene, c.997_998delGA and p.M424V, can cause complete achromatopsia. The vision of the patient was stationary until the third decade of life although the FAF was altered at the age of 22 years.
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Affiliation(s)
- Kazuki Kuniyoshi
- Department of Ophthalmology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8911, Japan.
| | - Sanae Muraki-Oda
- Department of Ophthalmology, Shiga University of Medical Science, Otsu, Japan
| | - Hisao Ueyama
- Department of Biochemistry and Molecular Biology, Shiga University of Medical Science, Otsu, Japan
| | - Futoshi Toyoda
- Department of Physiology, Shiga University of Medical Science, Otsu, Japan
| | - Hiroyuki Sakuramoto
- Department of Ophthalmology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8911, Japan
| | - Hisakazu Ogita
- Department of Biochemistry and Molecular Biology, Shiga University of Medical Science, Otsu, Japan
| | - Motohiro Irifune
- Department of Ophthalmology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8911, Japan
- Irifune Eye Clinic, Izumi, Japan
| | - Shuji Yamamoto
- Jin Eye Clinic, Nishinomiya, Japan
- Department of Ophthalmology, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Akira Nakao
- Department of Ophthalmology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8911, Japan
| | - Kazushige Tsunoda
- Laboratory of Visual Physiology, 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 Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Masahito Ohji
- Department of Ophthalmology, Shiga University of Medical Science, Otsu, Japan
| | - Yoshikazu Shimomura
- Department of Ophthalmology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, 589-8911, Japan
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48
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Chiang J(PW, Gorin MB. Challenges confronting precision medicine in the context of inherited retinal disorders. EXPERT REVIEW OF PRECISION MEDICINE AND DRUG DEVELOPMENT 2016. [DOI: 10.1080/23808993.2016.1152159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Aboshiha J, Dubis AM, Carroll J, Hardcastle AJ, Michaelides M. The cone dysfunction syndromes. Br J Ophthalmol 2016; 100:115-21. [PMID: 25770143 PMCID: PMC4717370 DOI: 10.1136/bjophthalmol-2014-306505] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 02/09/2015] [Indexed: 11/05/2022]
Abstract
The cone dysfunction syndromes are a heterogeneous group of inherited, predominantly stationary retinal disorders characterised by reduced central vision and varying degrees of colour vision abnormalities, nystagmus and photophobia. This review details the following conditions: complete and incomplete achromatopsia, blue-cone monochromatism, oligocone trichromacy, bradyopsia and Bornholm eye disease. We describe the clinical, psychophysical, electrophysiological and imaging findings that are characteristic to each condition in order to aid their accurate diagnosis, as well as highlight some classically held notions about these diseases that have come to be challenged over the recent years. The latest data regarding the genetic aetiology and pathological changes observed in the cone dysfunction syndromes are discussed, and, where relevant, translational avenues of research, including completed and anticipated interventional clinical trials, for some of the diseases described herein will be presented. Finally, we briefly review the current management of these disorders.
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Affiliation(s)
- Jonathan Aboshiha
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Adam M Dubis
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Joseph Carroll
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Alison J Hardcastle
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital, London, UK
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50
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Giblin JP, Comes N, Strauss O, Gasull X. Ion Channels in the Eye: Involvement in Ocular Pathologies. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 104:157-231. [PMID: 27038375 DOI: 10.1016/bs.apcsb.2015.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The eye is the sensory organ of vision. There, the retina transforms photons into electrical signals that are sent to higher brain areas to produce visual sensations. In the light path to the retina, different types of cells and tissues are involved in maintaining the transparency of avascular structures like the cornea or lens, while others, like the retinal pigment epithelium, have a critical role in the maintenance of photoreceptor function by regenerating the visual pigment. Here, we have reviewed the roles of different ion channels expressed in ocular tissues (cornea, conjunctiva and neurons innervating the ocular surface, lens, retina, retinal pigment epithelium, and the inflow and outflow systems of the aqueous humor) that are involved in ocular disease pathophysiologies and those whose deletion or pharmacological modulation leads to specific diseases of the eye. These include pathologies such as retinitis pigmentosa, macular degeneration, achromatopsia, glaucoma, cataracts, dry eye, or keratoconjunctivitis among others. Several disease-associated ion channels are potential targets for pharmacological intervention or other therapeutic approaches, thus highlighting the importance of these channels in ocular physiology and pathophysiology.
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Affiliation(s)
- Jonathan P Giblin
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Nuria Comes
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Xavier Gasull
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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