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Kim TH, Kim CZ, Lee SU, Lee SJ. Benign Concentric Annular Macular Dystrophy in a Young Woman. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2022. [DOI: 10.3341/jkos.2022.63.7.637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Purpose: Here, we report a case of benign concentric annular macular dystrophy associated with a visual field defect.Case summary: A 34-year-old woman presented with a visual field defect that was not accompanied by a deterioration in visual acuity. The patient’s best-corrected visual acuity was 1.25 in both eyes. No signs of anterior chamber inflammation were observed, and fundoscopy showed annular hypopigmentation at the fovea in both eyes. Annular hyperfluorescence was observed on fluorescein angiography due to the window defect. Automated perimetry demonstrated an annular paracentral scotoma in both eyes. The standard electroretinogram was normal, whereas optical coherence tomography showed a loss at the inner and outer boundaries of the foveal photoreceptors. The patient had no history of chloroquine or hydroxychloroquine intake, which excluded Bull’s eye maculopathy. The patient was observed without treatment for 2 years and no change was observed in her visual acuity or the appearance of the fovea.Conclusions: Benign concentric annular macular dystrophy should be considered in patients with annular hypopigmentation at the fovea without deterioration in the visual acuity of both eyes.
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Olivier G, Corton M, Intartaglia D, Verbakel SK, Sergouniotis PI, Le Meur G, Dhaenens CM, Naacke H, Avila-Fernández A, Hoyng CB, Klevering J, Bocquet B, Roubertie A, Sénéchal A, Banfi S, Muller A, Hamel CL, Black GC, Conte I, Roosing S, Zanlonghi X, Ayuso C, Meunier I, Manes G. Pathogenic variants in IMPG1 cause autosomal dominant and autosomal recessive retinitis pigmentosa. J Med Genet 2021; 58:570-578. [PMID: 32817297 DOI: 10.1136/jmedgenet-2020-107150] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/09/2020] [Accepted: 06/24/2020] [Indexed: 11/04/2022]
Abstract
BACKGROUND Inherited retinal disorders are a clinically and genetically heterogeneous group of conditions and a major cause of visual impairment. Common disease subtypes include vitelliform macular dystrophy (VMD) and retinitis pigmentosa (RP). Despite the identification of over 90 genes associated with RP, conventional genetic testing fails to detect a molecular diagnosis in about one third of patients with RP. METHODS Exome sequencing was carried out for identifying the disease-causing gene in a family with autosomal dominant RP. Gene panel testing and exome sequencing were performed in 596 RP and VMD families to identified additional IMPG1 variants. In vivo analysis in the medaka fish system by knockdown assays was performed to screen IMPG1 possible pathogenic role. RESULTS Exome sequencing of a family with RP revealed a splice variant in IMPG1. Subsequently, the same variant was identified in individuals from two families with either RP or VMD. A retrospective study of patients with RP or VMD revealed eight additional families with different missense or nonsense variants in IMPG1. In addition, the clinical diagnosis of the IMPG1 retinopathy-associated variant, originally described as benign concentric annular macular dystrophy, was also revised to RP with early macular involvement. Using morpholino-mediated ablation of Impg1 and its paralog Impg2 in medaka fish, we confirmed a phenotype consistent with that observed in the families, including a decreased length of rod and cone photoreceptor outer segments. CONCLUSION This study discusses a previously unreported association between monoallelic or biallelic IMPG1 variants and RP. Notably, similar observations have been reported for IMPG2.
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Affiliation(s)
- Guillaume Olivier
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, France
| | - Marta Corton
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM)-Center for Biomedical Network Research on Rare Diseases-(CIBERER), Madrid, Spain
| | - Daniela Intartaglia
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", Telethon Institute of Genetics and Medicine, Pozzuoli (NA), and Medical Genetics, Naples, Italy
| | - Sanne K Verbakel
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Panagiotis I Sergouniotis
- Manchester Royal Eye Hospital, Manchester Academic Health Science Centre, Central Manchester NHS Foundation Trust, Manchester Royal Eye Hospital, Manchester, M13 9WL, UK
| | - Guylène Le Meur
- Service Ophtalmologie, CHU Nantes, Nantes Université, Nantes, France
| | - Claire-Marie Dhaenens
- University Lille-Nord de France, INSERM U837, Lille, France
- Lille Neuroscience & Cognition, LilNCog, Lille, France
| | - Hélène Naacke
- Service d'ophtalmologie, Clinique Saint Joseph, Angouleme, Nouvelle Aquitaine, France
| | - Almudena Avila-Fernández
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM)-Center for Biomedical Network Research on Rare Diseases-(CIBERER), Madrid, Spain
| | - Carel B Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jeroen Klevering
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Béatrice Bocquet
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, France
| | - Agathe Roubertie
- Département de Neuropédiatrie, CHU Montpellier, Hôpital Gui de Chauliac, Montpellier, Hérault, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, Hérault, France
| | - Audrey Sénéchal
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, France
| | - Sandro Banfi
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", Telethon Institute of Genetics and Medicine, Naples, Italy
| | - Agnès Muller
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, France
| | - Christian L Hamel
- Service d'ophtalmologie, Hôpital Gui de Chauliac, CHU Montpellier, Montpellier, France
| | - Graeme C Black
- Department of Genetic Medicine, University of Manchester, Manchester, UK
| | - Ivan Conte
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", Telethon Institute of Genetics and Medicine, Pozzuoli (NA), and Medical Genetics, Naples, Italy
- Department of Biology, University of Naples Federico II, Napoli, Campania, Italy
| | - Susanne Roosing
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Xavier Zanlonghi
- Institut Ophtalmologique de l'Ouest, Eye Clinic Jules Verne, Nantes, France
| | - Carmen Ayuso
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM)-Center for Biomedical Network Research on Rare Diseases-(CIBERER), Madrid, Spain
- Department of Genetics & Genomics, Centro de Investigacion Biomedica en Red (CIBER) de Enfermedades Raras, ISCIII, Madrid, Spain
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- National Centre in Rare Diseases, Genetics of Sensory Diseases, CHU Montpellier, Montpellier, Languedoc-Roussillon, France
| | - Gaël Manes
- Institute for Neurosciences of Montpellier, University of Montpellier, Montpellier, France
- Institute for Neurosciences of Montpellier, INSERM U1051, Montpellier, France
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Ng CC, Carrera WM, McDonald HR, Agarwal A. Heterozygous CRX R90W mutation-associated adult-onset macular dystrophy with phenotype analogous to benign concentric annular macular dystrophy. Ophthalmic Genet 2020; 41:485-490. [PMID: 32689858 DOI: 10.1080/13816810.2020.1795890] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Background Historically, CRX mutations have been associated with cone-rod dystrophy, cone dystrophy, Leber's congenital amaurosis, and retinitis pigmentosa. There is recent emerging evidence of an adult-onset macular dystrophy phenotype. We review the published literature and discuss the first case of heterozygous CRX R90 W macular dystrophy. Materials and Methods The patient received serial ophthalmic examination and imaging. Genetic testing was performed by MyRetinaTracker with the use of a retinal dystrophy panel. Results A 55-year-old Caucasian male patient without a prior medical history presented for evaluation of decreased vision in the right eye. Visual acuity was 20/32 both eyes, and his fundus examination was notable for an incomplete ring-shaped macular atrophy with foveolar sparing in both eyes. Fundus autofluorescence was notable for hypo-autofluorescence of the ring and fluorescein angiography for transmission hyperfluorescence. Full-field ERG and EOG were normal, while mfERG showed central depression. His lesion was clinically diagnosed as benign concentric annular macular dystrophy, but genetic testing revealed a heterozygous mutation in CRX (c.268 C > T, p.R90 W). A three-generation family tree did not reveal other members with known macular dystrophy. Given the lack of documentable autosomal dominant inheritance and the presence of a CRX mutation, the patient's diagnosis was revised to adult-onset macular dystrophy. Conclusions We believe this to be the first case of adult onset macular dystrophy associated with heterozygous CRX R90 W mutation.
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Affiliation(s)
- Caleb C Ng
- Department of Ophthalmology, California Pacific Medical Center , San Francisco, CA, USA.,West Coast Retina Medical Group , San Francisco, CA, USA
| | - William M Carrera
- Department of Ophthalmology, California Pacific Medical Center , San Francisco, CA, USA
| | | | - Anita Agarwal
- Department of Ophthalmology, California Pacific Medical Center , San Francisco, CA, USA.,West Coast Retina Medical Group , San Francisco, CA, USA
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Sun L, Wang X, Hou S, Liang M, Yang J. Identification of MYO6 copy number variation associated with cochlear aplasia by targeted sequencing. Int J Pediatr Otorhinolaryngol 2020; 128:109689. [PMID: 31785455 DOI: 10.1016/j.ijporl.2019.109689] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 08/12/2019] [Accepted: 09/18/2019] [Indexed: 11/24/2022]
Abstract
Copy number variation is an extensively studied cause of hereditary diseases. However, its role in hereditary sensorineural deafness has been rarely reported. Using targeted sequencing, SNP array and qPCR, we found a novel 622.2 kb duplication of 6q14.1 in a patient with congenital sensorineural hearing loss and cochlear aplasia. The duplication included MYO6 and IMPG1 genes. FISH study confirmed that this duplication was inherited from the patient's mosaic mother.
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Affiliation(s)
- Lianhua Sun
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Xiaowen Wang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Shule Hou
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Min Liang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China
| | - Jun Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute Shanghai Jiaotong University School of Medicine, Shanghai, China; Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai, China.
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Jain A, Anantharaman G, Goyal A, Gopalakrishnan M. Multimodal imaging of benign concentric annular macular dystrophy. Indian J Ophthalmol 2019; 67:1719-1720. [PMID: 31546530 PMCID: PMC6786140 DOI: 10.4103/ijo.ijo_1911_18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Aarti Jain
- Department of Vitreoretina, Giridhar Eye Hospital, Kochi, Kerala, India
| | | | - Anubhav Goyal
- Department of Vitreoretina, Giridhar Eye Hospital, Kochi, Kerala, India
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6
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González-Gómez A, Romero-Trevejo JL, García-Ben A, García-Campos JM. Bull's eye maculopathy caused by a novel IMPG-1 mutation. Ophthalmic Genet 2018; 40:71-73. [PMID: 30589393 DOI: 10.1080/13816810.2018.1561903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Ana González-Gómez
- a Servicio de Oftalmología , Hospital Universitario Virgen de la Victoria , Málaga , Spain
| | | | - Antonio García-Ben
- b Servicio de Oftalmología , Hospital Clínico Universitario de Santiago , Santiago de Compostela , Spain
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Griffith JF, DeBenedictis MJ, Traboulsi EI. A novel dominant CRX mutation causes adult-onset macular dystrophy. Ophthalmic Genet 2017; 39:120-124. [DOI: 10.1080/13816810.2017.1373831] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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8
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Brandl C, Schulz HL, Charbel Issa P, Birtel J, Bergholz R, Lange C, Dahlke C, Zobor D, Weber BHF, Stöhr H. Mutations in the Genes for Interphotoreceptor Matrix Proteoglycans, IMPG1 and IMPG2, in Patients with Vitelliform Macular Lesions. Genes (Basel) 2017. [PMID: 28644393 PMCID: PMC5541303 DOI: 10.3390/genes8070170] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A significant portion of patients diagnosed with vitelliform macular dystrophy (VMD) do not carry causative mutations in the classic VMD genes BEST1 or PRPH2. We therefore performed a mutational screen in a cohort of 106 BEST1/PRPH2-negative VMD patients in two genes encoding secreted interphotoreceptor matrix proteoglycans-1 and -2 (IMPG1 and IMPG2). We identified two novel mutations in IMPG1 in two simplex VMD cases with disease onset in their early childhood, a heterozygous p.(Leu238Pro) missense mutation and a homozygous c.807 + 5G > A splice site mutation. The latter induced partial skipping of exon 7 of IMPG1 in an in vitro splicing assay. Furthermore, we found heterozygous mutations including three stop [p.(Glu226*), p.(Ser522*), p.(Gln856*)] and five missense mutations [p.(Ala243Pro), p.(Gly1008Asp), p.(Phe1016Ser), p.(Tyr1042Cys), p.(Cys1077Phe)] in the IMPG2 gene, one of them, p.(Cys1077Phe), previously associated with VMD. Asymptomatic carriers of the p.(Ala243Pro) and p.(Cys1077Phe) mutations show subtle foveal irregularities that could characterize a subclinical stage of disease. Taken together, our results provide further evidence for an involvement of dominant and recessive mutations in IMPG1 and IMPG2 in VMD pathology. There is a remarkable similarity in the clinical appearance of mutation carriers, presenting with bilateral, central, dome-shaped foveal accumulation of yellowish material with preserved integrity of the retinal pigment epithelium (RPE). Clinical symptoms tend to be more severe for IMPG1 mutations.
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Affiliation(s)
- Caroline Brandl
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, 93053 Regensburg, Germany;
- Institut für Humangenetik, Universität Regensburg, 93053 Regensburg, Germany; (H.L.S.); (B.H.F.W.)
- Lehrstuhl für Genetische Epidemiologie, Universität Regensburg, 93053 Regensburg, Germany
| | - Heidi L. Schulz
- Institut für Humangenetik, Universität Regensburg, 93053 Regensburg, Germany; (H.L.S.); (B.H.F.W.)
| | - Peter Charbel Issa
- Department of Ophthalmology, University of Bonn, 53113 Bonn, Germany;
- Oxford Eye Hospital, OUH NHS Foundation Trust and the Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford OX1 3BD, UK
| | - Johannes Birtel
- Department of Ophthalmology, University of Bonn, 53113 Bonn, Germany;
| | - Richard Bergholz
- Klinik für Augenheilkunde, Charité—Universitätsmedizin Berlin, 10117 Berlin, Germany;
| | - Clemens Lange
- Klinik für Augenheilkunde, Universitätsklinikum Freiburg, Medizinische Fakultät, Albert Ludwigs Universität Freiburg, 79085 Freiburg, Germany;
| | - Claudia Dahlke
- Klinik für Augenheilkunde, Universitätsklinikum Köln, 50937 Köln, Germany;
| | - Ditta Zobor
- Forschungsinstitut für Augenheilkunde, Universitätsklinikum Tübingen, 72076 Tübingen, Germany;
| | - Bernhard H. F. Weber
- Institut für Humangenetik, Universität Regensburg, 93053 Regensburg, Germany; (H.L.S.); (B.H.F.W.)
| | - Heidi Stöhr
- Institut für Humangenetik, Universität Regensburg, 93053 Regensburg, Germany; (H.L.S.); (B.H.F.W.)
- Correspondence: ; Tel.: +49-941-944-5424
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9
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Simunovic MP. Acquired color vision deficiency. Surv Ophthalmol 2015; 61:132-55. [PMID: 26656928 DOI: 10.1016/j.survophthal.2015.11.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 11/06/2015] [Accepted: 11/11/2015] [Indexed: 02/02/2023]
Abstract
Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations.
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Affiliation(s)
- Matthew P Simunovic
- Nuffield Laboratory of Ophthalmology, University of Oxford & Oxford Eye Hospital, University of Oxford NHS Trust, West Wing, John Radcliffe Hospital, Oxford OX3 9DU, UK.
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Adult-onset foveomacular vitelliform dystrophy: A fresh perspective. Prog Retin Eye Res 2015; 47:64-85. [DOI: 10.1016/j.preteyeres.2015.02.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 02/01/2015] [Accepted: 02/04/2015] [Indexed: 01/06/2023]
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11
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Marfany G, Gonzàlez-Duarte R. Clinical applications of high-throughput genetic diagnosis in inherited retinal dystrophies: Present challenges and future directions. World J Med Genet 2015; 5:14-22. [DOI: 10.5496/wjmg.v5.i2.14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 12/30/2014] [Accepted: 02/09/2015] [Indexed: 02/06/2023] Open
Abstract
The advent of next generation sequencing (NGS) techniques has greatly simplified the molecular diagnosis and gene identification in very rare and highly heterogeneous Mendelian disorders. Over the last two years, these approaches, especially whole exome sequencing (WES), alone or combined with homozygosity mapping and linkage analysis, have proved to be successful in the identification of more than 25 new causative retinal dystrophy genes. NGS-approaches have also identified a wealth of new mutations in previously reported genes and have provided more comprehensive information concerning the landscape of genotype-phenotype correlations and the genetic complexity/diversity of human control populations. Although whole genome sequencing is far more informative than WES, the functional meaning of the genetic variants identified by the latter can be more easily interpreted, and final diagnosis of inherited retinal dystrophies is extremely successful, reaching 80%, particularly for recessive cases. Even considering the present limitations of WES, the reductions in costs and time, the continual technical improvements, the implementation of refined bioinformatic tools and the unbiased comprehensive genetic information it provides, make WES a very promising diagnostic tool for routine clinical and genetic diagnosis in the future.
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12
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Meunier I, Manes G, Bocquet B, Marquette V, Baudoin C, Puech B, Defoort-Dhellemmes S, Audo I, Verdet R, Arndt C, Zanlonghi X, Le Meur G, Dhaenens CM, Hamel CP. Frequency and Clinical Pattern of Vitelliform Macular Dystrophy Caused by Mutations of Interphotoreceptor Matrix IMPG1 and IMPG2 Genes. Ophthalmology 2014; 121:2406-14. [DOI: 10.1016/j.ophtha.2014.06.028] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 04/28/2014] [Accepted: 06/18/2014] [Indexed: 11/30/2022] Open
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13
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Roosing S, Thiadens AAHJ, Hoyng CB, Klaver CCW, den Hollander AI, Cremers FPM. Causes and consequences of inherited cone disorders. Prog Retin Eye Res 2014; 42:1-26. [PMID: 24857951 DOI: 10.1016/j.preteyeres.2014.05.001] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 04/29/2014] [Accepted: 05/06/2014] [Indexed: 11/18/2022]
Abstract
Hereditary cone disorders (CDs) are characterized by defects of the cone photoreceptors or retinal pigment epithelium underlying the macula, and include achromatopsia (ACHM), cone dystrophy (COD), cone-rod dystrophy (CRD), color vision impairment, Stargardt disease (STGD) and other maculopathies. Forty-two genes have been implicated in non-syndromic inherited CDs. Mutations in the 5 genes implicated in ACHM explain ∼93% of the cases. On the contrary, only 21% of CRDs (17 genes) and 25% of CODs (8 genes) have been elucidated. The fact that the large majority of COD and CRD-associated genes are yet to be discovered hints towards the existence of unknown cone-specific or cone-sensitive processes. The ACHM-associated genes encode proteins that fulfill crucial roles in the cone phototransduction cascade, which is the most frequently compromised (10 genes) process in CDs. Another 7 CD-associated proteins are required for transport processes towards or through the connecting cilium. The remaining CD-associated proteins are involved in cell membrane morphogenesis and maintenance, synaptic transduction, and the retinoid cycle. Further novel genes are likely to be identified in the near future by combining large-scale DNA sequencing and transcriptomics technologies. For 31 of 42 CD-associated genes, mammalian models are available, 14 of which have successfully been used for gene augmentation studies. However, gene augmentation for CDs should ideally be developed in large mammalian models with cone-rich areas, which are currently available for only 11 CD genes. Future research will aim to elucidate the remaining causative genes, identify the molecular mechanisms of CD, and develop novel therapies aimed at preventing vision loss in individuals with CD in the future.
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Affiliation(s)
- Susanne Roosing
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | | | - Carel B Hoyng
- Department of Ophthalmology, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Caroline C W Klaver
- Department of Ophthalmology Erasmus Medical Centre, 3000 CA, Rotterdam, The Netherlands; Department of Epidemiology, Erasmus Medical Centre, 3000 CA, Rotterdam, The Netherlands
| | - Anneke I den Hollander
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB, Nijmegen, The Netherlands; Department of Ophthalmology, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Frans P M Cremers
- Department of Human Genetics, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands; Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
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14
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Mutations in IMPG1 cause vitelliform macular dystrophies. Am J Hum Genet 2013; 93:571-8. [PMID: 23993198 DOI: 10.1016/j.ajhg.2013.07.018] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 05/27/2013] [Accepted: 07/19/2013] [Indexed: 11/21/2022] Open
Abstract
Vitelliform macular dystrophies (VMD) are inherited retinal dystrophies characterized by yellow, round deposits visible upon fundus examination and encountered in individuals with juvenile Best macular dystrophy (BMD) or adult-onset vitelliform macular dystrophy (AVMD). Although many BMD and some AVMD cases harbor mutations in BEST1 or PRPH2, the underlying genetic cause remains unknown for many affected individuals. In a large family with autosomal-dominant VMD, gene mapping and whole-exome sequencing led to the identification of a c.713T>G (p.Leu238Arg) IMPG1 mutation, which was subsequently found in two other families with autosomal-dominant VMD and the same phenotype. IMPG1 encodes the SPACR protein, a component of the rod and cone photoreceptor extracellular matrix domains. Structural modeling indicates that the p.Leu238Arg substitution destabilizes the conserved SEA1 domain of SPACR. Screening of 144 probands who had various forms of macular dystrophy revealed three other IMPG1 mutations. Two individuals from one family affected by autosomal-recessive VMD were homozygous for the splice-site mutation c.807+1G>T, and two from another family were compound heterozygous for the mutations c.461T>C (p.Leu154Pro) and c.1519C>T (p.Arg507(∗)). Most cases had a normal or moderately decreased electrooculogram Arden ratio. We conclude that IMPG1 mutations cause both autosomal-dominant and -recessive forms of VMD, thus indicating that impairment of the interphotoreceptor matrix might be a general cause of VMD.
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Novel GUCA1A mutations suggesting possible mechanisms of pathogenesis in cone, cone-rod, and macular dystrophy patients. BIOMED RESEARCH INTERNATIONAL 2013; 2013:517570. [PMID: 24024198 PMCID: PMC3759255 DOI: 10.1155/2013/517570] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 06/19/2013] [Indexed: 01/06/2023]
Abstract
Here, we report two novel GUCA1A (the gene for guanylate cyclase activating protein 1) mutations identified in unrelated Spanish families affected by autosomal dominant retinal degeneration (adRD) with cone and rod involvement. All patients from a three-generation adRD pedigree underwent detailed ophthalmic evaluation. Total genome scan using single-nucleotide polymorphisms and then the linkage analysis were undertaken on the pedigree. Haplotype analysis revealed a 55.37 Mb genomic interval cosegregating with the disease phenotype on chromosome 6p21.31-q15. Mutation screening of positional candidate genes found a heterozygous transition c.250C>T in exon 4 of GUCA1A, corresponding to a novel mutation p.L84F. A second missense mutation, c.320T>C (p.I107T), was detected by screening of the gene in a Spanish patients cohort. Using bioinformatics approach, we predicted that either haploinsufficiency or dominant-negative effect accompanied by creation of a novel function for the mutant protein is a possible mechanism of the disease due to c.250C>T and c.320T>C. Although additional functional studies are required, our data in relation to the c.250C>T mutation open the possibility that transacting factors binding to de novo created recognition site resulting in formation of aberrant splicing variant is a disease model which may be more widespread than previously recognized as a mechanism causing inherited RD.
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Bandah-Rozenfeld D, Collin RWJ, Banin E, van den Born LI, Coene KLM, Siemiatkowska AM, Zelinger L, Khan MI, Lefeber DJ, Erdinest I, Testa F, Simonelli F, Voesenek K, Blokland EAW, Strom TM, Klaver CCW, Qamar R, Banfi S, Cremers FPM, Sharon D, den Hollander AI. Mutations in IMPG2, encoding interphotoreceptor matrix proteoglycan 2, cause autosomal-recessive retinitis pigmentosa. Am J Hum Genet 2010; 87:199-208. [PMID: 20673862 DOI: 10.1016/j.ajhg.2010.07.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 06/25/2010] [Accepted: 07/11/2010] [Indexed: 11/17/2022] Open
Abstract
Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal diseases caused by progressive degeneration of the photoreceptor cells. Using autozygosity mapping, we identified two families, each with three affected siblings sharing large overlapping homozygous regions that harbored the IMPG2 gene on chromosome 3. Sequence analysis of IMPG2 in the two index cases revealed homozygous mutations cosegregating with the disease in the respective families: three affected siblings of Iraqi Jewish ancestry displayed a nonsense mutation, and a Dutch family displayed a 1.8 kb genomic deletion that removes exon 9 and results in the absence of seven amino acids in a conserved SEA domain of the IMPG2 protein. Transient transfection of COS-1 cells showed that a construct expressing the wild-type SEA domain is properly targeted to the plasma membrane, whereas the mutant lacking the seven amino acids appears to be retained in the endoplasmic reticulum. Mutation analysis in ten additional index cases that were of Dutch, Israeli, Italian, and Pakistani origin and had homozygous regions encompassing IMPG2 revealed five additional mutations; four nonsense mutations and one missense mutation affecting a highly conserved phenylalanine residue. Most patients with IMPG2 mutations showed an early-onset form of RP with progressive visual-field loss and deterioration of visual acuity. The patient with the missense mutation, however, was diagnosed with maculopathy. The IMPG2 gene encodes the interphotoreceptor matrix proteoglycan IMPG2, which is a constituent of the interphotoreceptor matrix. Our data therefore show that mutations in a structural component of the interphotoreceptor matrix can cause arRP.
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Affiliation(s)
- Dikla Bandah-Rozenfeld
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Abd El-Aziz MM, El-Ashry MF, Barragan I, Marcos I, Borrego S, Antiñolo G, Bhattacharya SS. Molecular Genetic Analysis of Two Functional Candidate Genes in the Autosomal Recessive Retinitis Pigmentosa, RP25, Locus. Curr Eye Res 2009; 30:1081-7. [PMID: 16354621 DOI: 10.1080/02713680500351039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To identify the disease gene in five Spanish families with autosomal recessive retinitis pigmentosa (arRP) linked to the RP25 locus. Two candidate genes, EEF1A1 and IMPG1, were selected from the region between D6S280 and D6S1644 markers where the families are linked. The genes were selected as good candidates on the basis of their function, tissue expression pattern, and/or genetic data. METHODS A molecular genetic study was performed on DNA extracted from one parent and one affected member of each studied family. The coding exons, splice sites, and the 5' UTR of the genes were amplified by polymerase chain reaction (PCR). For mutation detection, direct sequence analysis was performed using the ABI 3100 automated sequencer. Segregation of an IMPG1 single nucleotide polymorphism (SNP) in all the families studied was analyzed by restriction enzyme digest of the amplified gene fragments. RESULTS In total, 15 SNPs were identified of which 7 were novel. Of the identified SNPs, one was insertion, two were deletions, five were intronic, six were missense, and one was located in the 5' UTR. These changes, however, were also identified in unaffected members of the families and/or 50 control Caucasians. The examined known IMPG1 SNP was not segregating with the disease phenotype but was correlating with the genetic data in all families studied. CONCLUSIONS Our results indicate that neither EEF1A1 nor IMPG1 could be responsible for RP25 in the studied families due to absence of any pathogenic variants. However, it is important to notice that the methodology used in this study cannot detect larger deletions that lie outside the screened regions or primer site mutations that exist in the heterozygous state. A role of both genes in other inherited forms of RP and/or retinal degenerations needs to be elucidated.
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Affiliation(s)
- Mai M Abd El-Aziz
- Department of Ophthalmology, Tanta University Hospital, Tanta, Egypt.
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Yang HC, Liang YJ, Wu YL, Chung CM, Chiang KM, Ho HY, Ting CT, Lin TH, Sheu SH, Tsai WC, Chen JH, Leu HB, Yin WH, Chiu TY, Chen CI, Fann CSJ, Wu JY, Lin TN, Lin SJ, Chen YT, Chen JW, Pan WH. Genome-wide association study of young-onset hypertension in the Han Chinese population of Taiwan. PLoS One 2009; 4:e5459. [PMID: 19421330 PMCID: PMC2674219 DOI: 10.1371/journal.pone.0005459] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Accepted: 04/11/2009] [Indexed: 12/23/2022] Open
Abstract
Young-onset hypertension has a stronger genetic component than late-onset counterpart; thus, the identification of genes related to its susceptibility is a critical issue for the prevention and management of this disease. We carried out a two-stage association scan to map young-onset hypertension susceptibility genes. The first-stage analysis, a genome-wide association study, analyzed 175 matched case-control pairs; the second-stage analysis, a confirmatory association study, verified the results at the first stage based on a total of 1,008 patients and 1,008 controls. Single-locus association tests, multilocus association tests and pair-wise gene-gene interaction tests were performed to identify young-onset hypertension susceptibility genes. After considering stringent adjustments of multiple testing, gene annotation and single-nucleotide polymorphism (SNP) quality, four SNPs from two SNP triplets with strong association signals (-log(10)(p)>7) and 13 SNPs from 8 interactive SNP pairs with strong interactive signals (-log(10)(p)>8) were carefully re-examined. The confirmatory study verified the association for a SNP quartet 219 kb and 495 kb downstream of LOC344371 (a hypothetical gene) and RASGRP3 on chromosome 2p22.3, respectively. The latter has been implicated in the abnormal vascular responsiveness to endothelin-1 and angiotensin II in diabetic-hypertensive rats. Intrinsic synergy involving IMPG1 on chromosome 6q14.2-q15 was also verified. IMPG1 encodes interphotoreceptor matrix proteoglycan 1 which has cation binding capacity. The genes are novel hypertension targets identified in this first genome-wide hypertension association study of the Han Chinese population.
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Affiliation(s)
- Hsin-Chou Yang
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Yu-Jen Liang
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Yi-Lin Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chia-Min Chung
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Kuang-Mao Chiang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Hung-Yun Ho
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - Chih-Tai Ting
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - Tsung-Hsien Lin
- Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung, Taiwan
| | - Sheng-Hsiung Sheu
- Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung, Taiwan
| | | | - Jyh-Hong Chen
- National Cheng Kung University Hospital, Tainan, Taiwan
| | - Hsin-Bang Leu
- National Yang-Ming University School of Medicine and Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wei-Hsian Yin
- Cheng Hsin Rehabilitation Medical Center, Taipei, Taiwan
| | | | | | - Cathy S. J. Fann
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Jer-Yuarn Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Teng-Nan Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Shing-Jong Lin
- National Yang-Ming University School of Medicine and Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yuan-Tsong Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Jaw-Wen Chen
- National Yang-Ming University School of Medicine and Taipei Veterans General Hospital, Taipei, Taiwan
- * E-mail: (J-WC); (WH-P)
| | - Wen-Harn Pan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
- * E-mail: (J-WC); (WH-P)
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Abd El-Aziz MM, Barragan I, O'Driscoll C, Borrego S, Abu-Safieh L, Pieras JI, El-Ashry MF, Prigmore E, Carter N, Antinolo G, Bhattacharya SS. Large-scale molecular analysis of a 34 Mb interval on chromosome 6q: major refinement of the RP25 interval. Ann Hum Genet 2007; 72:463-77. [PMID: 18510646 PMCID: PMC2689154 DOI: 10.1111/j.1469-1809.2008.00455.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A large scale bioinformatics and molecular analysis of a 34 Mb interval on chromosome 6q12 was undertaken as part of our ongoing study to identify the gene responsible for an autosomal recessive retinitis pigmentosa (arRP) locus, RP25. Extensive bioinformatics analysis indicated in excess of 110 genes within the region and we also noted unfinished sequence on chromosome 6q in the Human Genome Database, between 58 and 61.2 Mb. Forty three genes within the RP25 interval were considered as good candidates for mutation screening. Direct sequence analysis of the selected genes in 7 Spanish families with arRP revealed a total of 244 sequence variants, of which 67 were novel but none were pathogenic. This, together with previous reports, excludes 60 genes within the interval ( approximately 55%) as disease causing for RP. To investigate if copy number variation (CNV) exists within RP25, a comparative genomic hybridization (CGH) analysis was performed on a consanguineous family. A clone from the tiling path array, chr6tp-19C7, spanning approximately 100-Kb was found to be deleted in all affected members of the family, leading to a major refinement of the interval. This will eventually have a significant impact on cloning of the RP25 gene.
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Affiliation(s)
- M M Abd El-Aziz
- Department of Molecular Genetics, Institute of Ophthalmology, London EC1V 9EL, UK. Department of Ophthalmology, Tanta University Hospital, Tanta, Egypt
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Weleber RG, Gregory-Evans K. Retinitis Pigmentosa and Allied Disorders. Retina 2006. [DOI: 10.1016/b978-0-323-02598-0.50023-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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21
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Deutman AF, Hoyng CB, van Lith-Verhoeven JJ. Macular Dystrophies. Retina 2006. [DOI: 10.1016/b978-0-323-02598-0.50070-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Singh KK, Ristau S, Dawson WW, Krawczak M, Schmidtke J. Mapping of a macular drusen susceptibility locus in rhesus macaques to the homologue of human chromosome 6q14-15. Exp Eye Res 2005; 81:401-6. [PMID: 16185951 DOI: 10.1016/j.exer.2005.02.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Revised: 01/31/2005] [Accepted: 02/14/2005] [Indexed: 11/25/2022]
Abstract
Rhesus macaques (Macaca mulatta) are a natural model for retinal drusen formation. The present study aimed at clarifying whether chromosomal regions homologous to candidate genes for drusen formation and progression in humans are also associated with a drusen phenotype in rhesus macaques. Some 42 genetic markers from seven chromosomal regions implicated in macular degeneration syndromes in humans were tested for whether they identified homologous, polymorphic sequences in rhesus DNA. This was found to be the case for seven markers, all of which were subsequently screened for the presence of potentially disease-predisposing alleles in 52 randomly chosen adult animals from the Cayo Santiago population of rhesus macaques (Caribbean Primate Research Center, PR, USA). The high drusen prevalence expected in the Cayo Santiago colony was confirmed in our sample in that 38 animals were found to have drusen (73%). Logistic regression analysis revealed that some alleles of the rhesus homologue of anonymous human marker D6S1036 were consistently over-represented among affected animals. Of two candidate genes located in the respective region, allelic variation in one (IMPG1) showed strong association with drusen formation. We conclude that one or more genes located at the rhesus homologue of human 6q14-15 are likely to play a role in retinal drusen formation, a finding that represents a first step towards the identification of genetic factors implicated in macular drusen formation in rhesus macaques. This is an important tool for the separation of genetic and environmental factors which must occur before satisfactory management methods can be developed.
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Affiliation(s)
- Krishna K Singh
- Institut für Humangenetik, Medizinische Hochschule Hannover, Hannover, Germany
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Burton BJL, Holder GE, Duguid G, Gregory-Evans K. Optical coherence tomography findings in benign concentric annular dystrophy. Eye (Lond) 2004; 19:699-701. [PMID: 15184947 DOI: 10.1038/sj.eye.6701586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Chen Q, Cai S, Shadrach KG, Prestwich GD, Hollyfield JG. Spacrcan binding to hyaluronan and other glycosaminoglycans. Molecular and biochemical studies. J Biol Chem 2004; 279:23142-50. [PMID: 15044457 DOI: 10.1074/jbc.m401584200] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Photoreceptors project from the outer retinal surface into a specialized glycocalyx, the interphotoreceptor matrix (IPM), which contains hyaluronan (HA) and two novel proteoglycans, Spacr and Spacrcan. This matrix must be stable enough to function in the attachment of the retina to the outer eye wall yet porous enough to allow movement of metabolites between these tissues. How this matrix is organized is not known. HA is a potential candidate in IPM organization since biochemical studies show that these proteoglycans bind HA. RHAMM (receptor for HA-mediated motility)-type HA binding motifs (HABMs) are present in their deduced amino acid sequence and may be the sites of this HA interaction. To test this hypothesis, we subcloned three fragments of mouse Spacrcan that contain the putative HABMs. We found that each recombinant fragment binds HA. Binding decreased when residues in the HABMs were mutated. This provides direct evidence that the RHAMM-type HABMs in Spacrcan are involved in hyaluronan binding. Since chondroitin sulfate and heparan sulfate proteoglycans are important for retinal development and function, we also evaluated the binding of these recombinant proteins to heparin and chondroitin sulfates, the glycosaminoglycan side chain of these proteoglycans. We found that each recombinant protein bound to both heparin and chondroitin sulfates. Binding to chondroitin sulfates involved these HABMs, because mutagenesis reduced binding. Binding to heparin was probably not mediated through these HABMs since heparin binding persisted following their mutagenesis. These studies provide the first evidence defining the sites of protein-carbohydrate interaction of molecules present in the IPM.
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Affiliation(s)
- Qiuyun Chen
- Cole Eye Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
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