101
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Georgiou M, Fujinami K, Michaelides M. Inherited retinal diseases: Therapeutics, clinical trials and end points-A review. Clin Exp Ophthalmol 2021; 49:270-288. [PMID: 33686777 DOI: 10.1111/ceo.13917] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/22/2021] [Accepted: 03/01/2021] [Indexed: 12/18/2022]
Abstract
Inherited retinal diseases (IRDs) are a clinically and genetically heterogeneous group of disorders characterised by photoreceptor degeneration or dysfunction. These disorders typically present with severe vision loss that can be progressive, with disease onset ranging from congenital to late adulthood. The advances in genetics, retinal imaging and molecular biology, have conspired to create the ideal environment for establishing treatments for IRDs, with the first approved gene therapy and the commencement of multiple clinical trials. The scope of this review is to familiarise clinicians and scientists with the current management and the prospects for novel therapies for: (1) macular dystrophies, (2) cone and cone-rod dystrophies, (3) cone dysfunction syndromes, (4) Leber congenital amaurosis, (5) rod-cone dystrophies, (6) rod dysfunction syndromes and (7) chorioretinal dystrophies. We also briefly summarise the investigated end points for the ongoing trials.
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Affiliation(s)
- Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Kaoru Fujinami
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.,Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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102
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Abbasi B, Rizzo JF. Advances in Neuroscience, Not Devices, Will Determine the Effectiveness of Visual Prostheses. Semin Ophthalmol 2021; 36:168-175. [PMID: 33734937 DOI: 10.1080/08820538.2021.1887902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Background: Innovations in engineering and neuroscience have enabled the development of sophisticated visual prosthetic devices. In clinical trials, these devices have provided visual acuities as high as 20/460, enabled coarse navigation, and even allowed for reading of short words. However, long-term commercial viability arguably rests on attaining even better vision and more definitive improvements in tasks of daily living and quality of life. Purpose: Here we review technological and biological obstacles in the implementation of visual prosthetics. Conclusions: Research in the visual prosthetic field has tackled significant technical challenges, including biocompatibility, signal spread through neural tissue, and inadvertent activation of passing axons; however, significant gaps in knowledge remain in the realm of neuroscience, including the neural code of vision and visual plasticity. We assert that further optimization of prosthetic devices alone will not provide markedly improved visual outcomes without significant advances in our understanding of neuroscience.
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Affiliation(s)
- Bardia Abbasi
- Neuro-Ophthalmology Service, Department of Ophthalmology, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, USA
| | - Joseph F Rizzo
- Neuro-Ophthalmology Service, Department of Ophthalmology, Massachusetts Eye and Ear and Harvard Medical School, Boston, MA, USA
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103
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Varin J, Bouzidi N, Dias MMDS, Pugliese T, Michiels C, Robert C, Desrosiers M, Sahel JA, Audo I, Dalkara D, Zeitz C. Restoration of mGluR6 Localization Following AAV-Mediated Delivery in a Mouse Model of Congenital Stationary Night Blindness. Invest Ophthalmol Vis Sci 2021; 62:24. [PMID: 33729473 PMCID: PMC7980044 DOI: 10.1167/iovs.62.3.24] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Complete congenital stationary night blindness (cCSNB) is an incurable inherited retinal disorder characterized by an ON-bipolar cell (ON-BC) defect. GRM6 mutations are the third most prevalent cause of cCSNB. The Grm6-/- mouse model mimics the human phenotype, showing no b-wave in the electroretinogram (ERG) and a loss of mGluR6 and other proteins of the same cascade at the outer plexiform layer (OPL). Our aim was to restore protein localization and function in Grm6-/- adult mice targeting specifically ON-BCs or the whole retina. Methods Adeno-associated virus-encoding Grm6 under two different promoters (GRM6-Grm6 and CAG-Grm6) were injected intravitreally in P15 Grm6-/- mice. ERG recordings at 2 and 4 months were performed in Grm6+/+, untreated and treated Grm6-/- mice. Similarly, immunolocalization studies were performed on retinal slices before or after treatment using antibodies against mGluR6, TRPM1, GPR179, RGS7, RGS11, Gβ5, and dystrophin. Results Following treatment, mGluR6 was localized to the dendritic tips of ON-BCs when expressed with either promoter. The relocalization efficiency in mGluR6-transduced retinas at the OPL was 2.5% versus 11% when the GRM6-Grm6 and CAG-Grm6 were used, respectively. Albeit no functional rescue was seen in ERGs, relocalization of TRPM1, GPR179, and Gβ5 was also noted using both constructs. The restoration of the localization of RGS7, RGS11, and dystrophin was more obvious in retinas treated with GRM6-Grm6 than in retinas treated with CAG-Grm6. Conclusions Our findings show the potential of treating cCSNB with GRM6 mutations; however, it appears that the transduction rate must be improved to restore visual function.
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Affiliation(s)
- Juliette Varin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Nassima Bouzidi
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Thomas Pugliese
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Camille Robert
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France.,Fondation Ophtalmologique Adolphe de Rothschild, Paris, France.,Academie des Sciences, Institut de France, Paris, France.,Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France.,Institute of Ophthalmology, University College of London, London, United Kingdom
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
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104
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Delle Fave M, Cordonnier M, Vallee L, Condroyer C, Zeitz C, Balikova I. Congenital stationary night blindness in a patient with mild learning disability due to a compound heterozygous microdeletion of 15q13 and a missense mutation in TRPM1. Ophthalmic Genet 2021; 42:296-299. [PMID: 33691579 DOI: 10.1080/13816810.2021.1897846] [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: 10/22/2022]
Abstract
The complete form of congenital stationary night blindness (cCSNB) represents a non-progressive retinal disorder characterized by night vision problems and often congenital nystagmus, reduced vision, high myopia, strabismus and normal fundus appearance. Clinically this form of CSNB can be diagnosed by full-field electroretinogram. The mode of inheritance can be X-linked and autosomal recessive with mutations in genes coding for proteins mainly present at the dendritic tips of ON-bipolar cells. Mutations in NYX, GRM6, GPR179, LRIT3 and TRPM1 lead to this condition. The latter gene defect represents the major form underlying cCSNBC. It codes for the melastatin-related transient receptor 1 expressed in the inner nuclear layer of the retina, with the protein localized in ON-bipolar cells. To date, various homozygous or compound heterozygous mutations in TRPM1 have been reported. Small chromosomal rearrangements are frequent cause of mental retardation. In rare cases deletions can overlap with a mutation on the remaining chromosome and lead to a recessive disorder. Here, we describe a patient with mild neurological deficiencies and cCSNB caused by a microdeletion on 15q32 overlapping with a TRPM1 variant.
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Affiliation(s)
- M Delle Fave
- Ophthalmology Service, CUB Hopital Erasme, Brussels, Belgium
| | - M Cordonnier
- Ophthalmology Service, CUB Hopital Erasme, Brussels, Belgium
| | - L Vallee
- Neuropediatric Service, University Hospital Lille, Lille, France
| | - C Condroyer
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - C Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - I Balikova
- Ophthalmology Service, University Hospital Gasthuisberg, Leuven, Belgium
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105
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Coco-Martin RM, Diego-Alonso M, Orduz-Montaña WA, Sanabria MR, Sanchez-Tocino H. Descriptive Study of a Cohort of 488 Patients with Inherited Retinal Dystrophies. Clin Ophthalmol 2021; 15:1075-1084. [PMID: 33727790 PMCID: PMC7955737 DOI: 10.2147/opth.s293381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Accepted: 02/04/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To analyze the distribution of inherited retinal diseases (IRDs), describe the clinical characteristics of patients, and determine the percentages of patients with genetic diagnosis in the Castilla y Leon region of Spain. Methods All patients with an IRD seen in the two major referral units of Castilla y Leon during a 20-year period were included. The ages at symptom onset, diagnosis, and the last visit; sex; family history; history of consanguinity; type of inheritance; status of the fundus and electroretinogram findings; lens and macular status, visual acuity; and visual field data were recorded. Patients were divided into those with retinitis pigmentosa (RP) and all others. Gene mutations were gathered when available. Results Four hundred eighty-eight patients with IRDs were studied: 216 (44.26%) with RP of which 34 (15.74%) had syndromic diseases, and 272 had other conditions being 161 (59,19%) macular dystrophies. The mean delay in diagnosis was 6–16.2 years respectively. For the RP group the mean age at the last visit was 47.96±17,26; mean age of cataract surgery was 48.30 ± 12.01 years; and the foveal area was preserved in 74 (35.07%) patients, atrophic in 101 (47.87%), and edematous in 36 (17.06%). A genetic study had been performed in 58 (26.85%) of patients with RP and 71 (26,1%) of the rest, being indeterminate in 17 (29.31%) out of RP group and 20 (28.16%) out of the others. Conclusion Clinical characteristics are comparable to other published series. There is a significant delay in diagnosis. The number of patients with IRDs and available genetic diagnosis, thus being possible candidates for undergoing personalized treatments including gene therapy in our region is low and must be improved.
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Affiliation(s)
- Rosa M Coco-Martin
- Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain.,Red Temática de Investigación Cooperativa en Salud de Oftalmologia (Oftared), Instituto de Salud Carlos III, Madrid, Spain
| | - Miguel Diego-Alonso
- Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain.,Department of Ophthalmology, Hospital Universitario Río Hortega, Valladolid, Spain
| | - W Andres Orduz-Montaña
- Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain
| | - M Rosa Sanabria
- Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain.,Department of Ophthalmology, Complejo Hospitalario De Palencia, Palencia, Spain
| | - Hortensia Sanchez-Tocino
- Instituto Universitario de Oftalmobiología Aplicada (IOBA), University of Valladolid, Valladolid, Spain.,Department of Ophthalmology, Hospital Universitario Río Hortega, Valladolid, Spain
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106
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Suppiej A, Ceccato C, Maritan V, Cermakova I, Colavito D, Leon A. Exome sequencing and electro-clinical features in pediatric patients with very early-onset retinal dystrophies: A cohort study. Eur J Paediatr Neurol 2021; 31:1-9. [PMID: 33529788 DOI: 10.1016/j.ejpn.2021.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/01/2021] [Accepted: 01/10/2021] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND OBJECTIVE Inherited retinal dystrophies (IRDs) are a major cause of childhood blindness. Timely diagnosis requires a high level of clinical suspicion from both neurologists and ophthalmologists and is increasingly important given recent advancements in gene therapy. We focused our study on genotype-phenotype associations in very early-onset forms of retinal dystrophy, the least well characterized and most challenging diagnostic subgroup. METHODS From January 12, 2015 to March 31, 2017, we prospectively performed whole exome sequencing targeted on the phenotype of non-syndromic IRDs and phenotype characterization in a cohort of 68 children affected by very early-onset inherited retinal dystrophies, defined by the onset before five years of age. Phenotype parameters included age at onset, clinical presentation, ophthalmic evaluation, electrophysiological patterns and clinical course. RESULTS A genetically confirmed diagnosis was achieved in 50 out of 60 (83%) families. The median age at onset was 4 months (<6 m in 70%, < 2 y in 82% of the cases). Clinical presentation was associated with visual loss and nystagmus in the majority of patients. Three (CNGB3, CNGA3 and CACNA1F) out of 22 genes considered pathogenic in the cohort, accounted for 51% of all IRD's, all within the class of stationary IRDs. CONCLUSIONS This study reports on the largest cohort of very early-onset retinal dystrophies, including a description of electroretinography patterns. The electro-clinical phenotype coupled with genetic diagnosis provided additional clues for child neurologists dealing with low vision and nystagmus in infancy. A high level of clinical suspicion improves the diagnosis with important implications for the future of the affected child.
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Affiliation(s)
- A Suppiej
- Department of Medical Sciences, Paediatric Section, University of Ferrara, Italy; Paediatric University Hospital of Padova- Neuro-ophthalmology Program, Italy; Robert Hollman Foundation, Padova, Italy.
| | - C Ceccato
- Robert Hollman Foundation, Padova, Italy
| | - V Maritan
- Paediatric University Hospital of Padova- Neuro-ophthalmology Program, Italy; Ophthalmology Unit, Azienda ULSS 6 Euganea, Padova, Italy
| | | | - D Colavito
- Research & Innovation (R&I Genetics), Padova, Italy
| | - A Leon
- Research & Innovation (R&I Genetics), Padova, Italy
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107
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Leahy KE, Wright T, Grudzinska Pechhacker MK, Audo I, Tumber A, Tavares E, MacDonald H, Locke J, VandenHoven C, Zeitz C, Heon E, Buncic JR, Vincent A. Optic Atrophy and Inner Retinal Thinning in CACNA1F-related Congenital Stationary Night Blindness. Genes (Basel) 2021; 12:genes12030330. [PMID: 33668843 PMCID: PMC7996180 DOI: 10.3390/genes12030330] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/06/2021] [Accepted: 02/20/2021] [Indexed: 12/25/2022] Open
Abstract
Hemizygous pathogenic variants in CACNA1F lead to defective signal transmission from retinal photoreceptors to bipolar cells and cause incomplete congenital stationary night blindness in humans. Although the primary defect is at the terminal end of first-order neurons (photoreceptors), there is limited knowledge of higher-order neuronal changes (inner retinal) in this disorder. This study aimed to investigate inner retinal changes in CACNA1F-retinopathy by analyzing macular ganglion cell layer-inner plexiform layer (GCL-IPL) thickness and optic disc pallor in 22 subjects with molecularly confirmed CACNA1F-retinopathy. Detailed ocular phenotypic data including distance and color vision, refraction and electroretinogram (ERG) were collected. Distance vision was universally reduced (mean: 0.42 LogMAR), six had abnormal color vision and myopia was common (n = 15; mean: −6.32 diopters). Mean GCL-IPL thickness was significantly lower in patients (55.00 µm) compared to age-matched controls (n = 87; 84.57 µm; p << 0.001). The GCL-IPL thickness correlated with scotopic standard (p = 0.04) and bright-flash (p = 0.014) ERG b/a ratios and photopic b-wave amplitudes (p = 0.05). Twenty-one patients had some degree of disc pallor (bilateral in 19). Fifteen putative disease-causing, including five novel variants were identified. This study establishes macular inner retinal thinning and optic atrophy as characteristic features of CACNA1F-retinopathy, which are independent of myopia and could impact potential future treatment strategies.
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Affiliation(s)
- Kate E Leahy
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
| | - Tom Wright
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
- Kensington Eye Institute, Toronto, ON M5T 3A9, Canada
| | - Monika K Grudzinska Pechhacker
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
| | - Isabelle Audo
- INSERM, CNRS, Institut de la Vision, Sorbonne Université, 75012 Paris, France; (I.A.); (C.Z.)
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, 75012 Paris, France
- Institute of Ophthalmology, University College of London, London EC1V 9EL, UK
| | - Anupreet Tumber
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
| | - Erika Tavares
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada;
| | - Heather MacDonald
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Department of Genetic Counselling, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Jeff Locke
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
| | - Cynthia VandenHoven
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
| | - Christina Zeitz
- INSERM, CNRS, Institut de la Vision, Sorbonne Université, 75012 Paris, France; (I.A.); (C.Z.)
| | - Elise Heon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada;
| | - J Raymond Buncic
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
| | - Ajoy Vincent
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada; (K.E.L.); (M.K.G.P.); (A.T.); (H.M.); (J.L.); (C.V.); (E.H.); (J.R.B.)
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON M5T 3A9, Canada;
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada;
- Correspondence: ; Tel.: +1-416-813-1500
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Zolnikova IV, Kadyshev VV, Marakhonov AV, Zinchenko RA, Cherniak AB, Milash SV, Kogoleva LV, Bobrovskaya YA, Kokoeva NS, Egorova IV, Rogova SY. [Fundus albipunctatus with mutations in the RDH5 gene (clinical case)]. Vestn Oftalmol 2021; 137:68-73. [PMID: 33610152 DOI: 10.17116/oftalma202113701168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The article describes a clinical case of a 14-year old patient with RDH5 mutations (OMIM *601617) in patient with fundus albipunctatus (OMIM #136880) and characteristic biomarkers of this disease with previously described pathogenic variant of nucleotic sequence in exon 3 of the RDH5 gene (NM_002905.3:c.500G>A), causing a missense change (p.Arg167His) in heterozygous state and previously not described pathogenic variant of nucleotic sequence in exon 5 of the RDH5 gene (NM_002905.3:c.838C>T), leading to a missense change (p.Arg280Cys) in heterozygous state with characteristic biomarkers of the disease. Best-corrected visual acuity (BCVA) was 20/20. Nyctalopia was accompanied by reduced b-wave of scotopic (dark-adapted 0.01) ERG and decreased amplitude of a- and b-waves of maximum (dark-adapted 3) ERG. Decreased amplitude of the a- and b-waves of photopic (light-adapted 3) ERG and the amplitude of high-frequency (light-adapted 30 Hz) Flicker ERG shows the involvement of retinal cone system in the process. Fundus autofluorescence imaging of both eyes produced fuzzy and grainy images with slight hyperfluorescence of retinal flecks. Optical coherence tomography showed focal thickening centered in the photoreceptor outer segment corresponding to the multiple discrete albipunctate dots.
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Affiliation(s)
- I V Zolnikova
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - V V Kadyshev
- N.P. Bochkov Research Centre for Medical Genetics, Moscow, Russia
| | - A V Marakhonov
- N.P. Bochkov Research Centre for Medical Genetics, Moscow, Russia
| | - R A Zinchenko
- N.P. Bochkov Research Centre for Medical Genetics, Moscow, Russia.,Moscow Regional Research and Clinical Institute (MONIKI), Moscow, Russia
| | - A B Cherniak
- Pirogov Russian National Research Medical University, Moscow, Russia
| | - S V Milash
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - L V Kogoleva
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - Yu A Bobrovskaya
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - N S Kokoeva
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - I V Egorova
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - S Yu Rogova
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
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109
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Kobal N, Krašovec T, Šuštar M, Volk M, Peterlin B, Hawlina M, Fakin A. Stationary and Progressive Phenotypes Caused by the p.G90D Mutation in Rhodopsin Gene. Int J Mol Sci 2021; 22:ijms22042133. [PMID: 33669941 PMCID: PMC7924842 DOI: 10.3390/ijms22042133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 12/30/2022] Open
Abstract
Mutations in rhodopsin gene (RHO) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8-71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB (N = 3, 20%) sector RP (N = 3, 20%), pericentral RP (N = 1, 6.7%) and classic RP (N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal-Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report.
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Affiliation(s)
- Nina Kobal
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva ulica 46, 1000 Ljubljana, Slovenia; (N.K.); (T.K.); (M.Š.); (M.H.)
| | - Tjaša Krašovec
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva ulica 46, 1000 Ljubljana, Slovenia; (N.K.); (T.K.); (M.Š.); (M.H.)
| | - Maja Šuštar
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva ulica 46, 1000 Ljubljana, Slovenia; (N.K.); (T.K.); (M.Š.); (M.H.)
| | - Marija Volk
- Clinical Institute of Medical Genetics, University Medical Centre Ljubljana, Šlajmerjeva ulica 4, 1000 Ljubljana, Slovenia; (M.V.); (B.P.)
| | - Borut Peterlin
- Clinical Institute of Medical Genetics, University Medical Centre Ljubljana, Šlajmerjeva ulica 4, 1000 Ljubljana, Slovenia; (M.V.); (B.P.)
| | - Marko Hawlina
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva ulica 46, 1000 Ljubljana, Slovenia; (N.K.); (T.K.); (M.Š.); (M.H.)
| | - Ana Fakin
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva ulica 46, 1000 Ljubljana, Slovenia; (N.K.); (T.K.); (M.Š.); (M.H.)
- Correspondence:
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Memmi B, Miere A, Zambrowski O, Souied EH. [Decreased visual acuity as presenting sign of a late case of congenital stationary night blindness: The role of ERG]. J Fr Ophtalmol 2021; 44:e365-e368. [PMID: 33608178 DOI: 10.1016/j.jfo.2020.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/17/2020] [Accepted: 07/30/2020] [Indexed: 11/18/2022]
Affiliation(s)
- B Memmi
- Service d'ophtalmologie, centre hospitalier intercommunal de Créteil, université Paris Est-Créteil, 40, avenue de Verdun, 94000 Créteil, France.
| | - A Miere
- Service d'ophtalmologie, centre hospitalier intercommunal de Créteil, université Paris Est-Créteil, 40, avenue de Verdun, 94000 Créteil, France
| | - O Zambrowski
- Service d'ophtalmologie, centre hospitalier intercommunal de Créteil, université Paris Est-Créteil, 40, avenue de Verdun, 94000 Créteil, France
| | - E H Souied
- Service d'ophtalmologie, centre hospitalier intercommunal de Créteil, université Paris Est-Créteil, 40, avenue de Verdun, 94000 Créteil, France
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Ilhan C, Citirik M, Teke MY, Dulger SC. Clinical Findings in Four Siblings with Genetically Proven Oguchi Disease. J Curr Ophthalmol 2021; 32:390-394. [PMID: 33553842 PMCID: PMC7861099 DOI: 10.4103/joco.joco_155_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 07/29/2020] [Accepted: 08/04/2020] [Indexed: 11/04/2022] Open
Abstract
Purpose To assess the clinical findings in normal daylight status and 3 h of dark-adapted status in family members with Oguchi disease (OD). Methods Four siblings with OD and their parents were included in this case series. The presence of disease was confirmed with genetic analysis and comprehensive clinical evaluation. Corrected distant visual acuity (CDVA), automated visual field analysis (VFA), optical coherence tomography (OCT), OCT angiography (OCTA), colored fundus photography, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA), electroretinography (ERG), and dark adaptation test (DAT) results were obtained in normal daylight status. On the next day, after 3 h of dark adaptation, the patients were re-evaluated. The findings obtained in normal daylight status and 3 h dark-adapted status were compared. Results The mean age of the four sibling subjects was 15.25 ± 2.2 years. All subjects had 20/20 CDVA and normal VFA. There was no abnormality in OCT and OCTA in normal daylight status and 3 h of dark-adapted status. Colored fundus photographs showed characteristic golden-yellow colored reflex in the mid-peripheral retina in normal daylight status, and discoloration in 3 h of dark-adapted status. In FAF and FFA, no abnormal pattern was observed in normal daylight status and 3 h of dark-adapted status. ERG showed rod function alterations and normal cone function. DAT showed delayed rod adaptation and normal cone adaptation. ERG and DAT findings remained unchanged after 3 h of dark adaptation. Conclusion After 3 h of dark adaptation, golden-yellow fundus color returns to normal in patients with OD; however, rod function alterations and normal cone function in ERG, as well as delayed rod adaptation and normal cone adaptation in DAT remain unchanged.
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Affiliation(s)
- Cagri Ilhan
- Department of Ophthalmology, Hatay State Hospital, Hatay, Turkey
| | - Mehmet Citirik
- Department of Ophthalmology, Ankara Ulucanlar Eye Education and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Mehmet Yasin Teke
- Department of Ophthalmology, Ankara Ulucanlar Eye Education and Research Hospital, University of Health Sciences, Ankara, Turkey
| | - Selda Celik Dulger
- Department of Ophthalmology, Ankara Ulucanlar Eye Education and Research Hospital, University of Health Sciences, Ankara, Turkey
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Kishimoto N, Hayashi T, Mizobuchi K, Kubota M, Nakano T. Vitamin A deficiency after prolonged intake of an unbalanced diet in a Japanese hemodialysis patient. Doc Ophthalmol 2021; 143:85-91. [PMID: 33544296 DOI: 10.1007/s10633-021-09823-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 01/20/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND In industrialized countries, vitamin A deficiency (VAD) is extremely rare, except association with bariatric surgeries and hepatobiliary disorders. It is unusual that VAD develops during hemodialysis due to reduced glomerular filtration of vitamin A-binding protein. We reported the case of a 58-year-old Japanese male hemodialysis patient diagnosed with VAD. CASE PRESENTATION The patient undergoing hemodialysis for more than 15 years presented with progressive photophobia and night blindness and was ophthalmologically examined. He denied a history of cancer or hepatobiliary disease and reported that he loved eating prepackaged noodle bowls and foods, with prolonged low intake of fruits/vegetables. He had good visual acuity. Fundus images showed numerous white dots in the midperipheral retinae, but no degenerative changes. In baseline full-field electroretinography (ERG), b-wave responses were extremely reduced in rod ERG, a-wave amplitudes in standard-flash/strong-flash ERG were reduced to 20-25% of our controls, a- and b-wave amplitudes in cone ERG were reduced to 40-50% of the controls. Whole-exome sequencing identified no pathogenic variant for any inherited retinal disorder. He was diagnosed with VAD because of reduced serum vitamin A levels and treated with retinol palmitate. Two months after treatment commencement, the serum vitamin A level was within the normal range. Full-field ERG showed that the scotopic ERG responses markedly improved compared with baseline. CONCLUSIONS This is the first report of VAD associated with undernutrition in the Japanese hemodialysis population.
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Affiliation(s)
- Nanami Kishimoto
- Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, 6-41-2 Aoto, Katsushika-ku, Tokyo, 125-8506, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, 6-41-2 Aoto, Katsushika-ku, Tokyo, 125-8506, Japan.
| | - Kei Mizobuchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Masaomi Kubota
- Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, 6-41-2 Aoto, Katsushika-ku, Tokyo, 125-8506, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
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Muftuoglu IK, Al-Sheikh M, J S, Rasheed MA, Singh SR, Chhablani J. Imaging in inherited retinal disorders. Eur J Ophthalmol 2021; 31:1656-1676. [PMID: 33525895 DOI: 10.1177/1120672121990578] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inherited retinal diseases, which results from mutations in over 260 identified genes, affect more than 2 million people globally. The diseases mostly cause severe vision loss in young working population and have severe impact on social economic status of the population. Advances in retinal imaging techniques along with developments in gene identification and cell biology techniques have yielded to a better understanding of the genetic and biochemical mechanisms causing these diseases. Retinal imaging along with through ophthalmological examination is essential to make an accurate diagnosis, to decrease the burden of unneccessary anciliary tests and to select the potential patients that can get benefit from the gene treatment. The purpose of the review is to yield an update on inherited retinal diseases by highlighting microstructural changes in retina and to summarize the retinal changes detected by currently available multimodal imaging techniques.
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Affiliation(s)
- Ilkay Kilic Muftuoglu
- Department of Ophthalmology, Istanbul Training and Research Hospital, Istanbul, Turkey
| | - Mayss Al-Sheikh
- Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Sushma J
- LV Prasad Eye Institute, Hyderabad, Telangana, India
| | | | - Sumit Randhir Singh
- Jacobs Retina Center at Shiley Eye Center, University of California, San Diego, La Jolla, CA, USA
| | - Jay Chhablani
- UPMC Eye Center, University of Pittsburgh, Pittsburgh, PA, USA
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Nassisi M, Tepelus T, Corradetti G, Sadda SR. Relationship Between Choriocapillaris Flow and Scotopic Microperimetry in Early and Intermediate Age-related Macular Degeneration. Am J Ophthalmol 2021; 222:302-309. [PMID: 32360341 DOI: 10.1016/j.ajo.2020.04.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 04/17/2020] [Accepted: 04/17/2020] [Indexed: 12/28/2022]
Abstract
PURPOSE To evaluate the correlation between choriocapillaris (CC) flow alterations and scotopic macular sensitivity (sMS) in patients with early and intermediate age-related macular degeneration (AMD). DESIGN Prospective cross-sectional study. METHODS We acquired 2 3 × 3 mm and 2 6 × 6 mm swept-source optical coherence tomography angiography (OCTA) images of 1 eye of consecutive early or intermediate AMD patients at the Doheny UCLA Eye Centers. After 30 minutes of dark adaptation, the same eye underwent scotopic microperimetry with an 18-degree-wide grid (52 stimuli) centered on the fovea. The 2 en face CC angiograms obtained from each scan pattern were compensated for signal loss and averaged. The main outcome measures were correlation between percentages of flow deficits (FD3mm and FD6mm) and sMS in the central 10° (MS10) and the overall pattern (MS18). RESULTS Thirty eyes of 30 patients were enrolled, with 14 (46.7%) having subretinal drusenoid deposits (SDD). In the averaged OCTA scans, the FD3mm was 12.56% ± 2.41% while the FD6mm was 9.33% ± 1.84%. The mean MS10 and MS18 were 13.84 ± 5.89 dB and 14.64 ± 5.21 dB, respectively. For the MS10, the multivariate regression analysis showed a significant association only with FD3mm (β: -0.628, P < .001) while the MS18 was significantly correlated with both SDD (β: -0.32, P = .047) and FD6mm (β: -0.473, P = .005). CONCLUSIONS Our study reports a significant correlation between the CC flow impairment and the sMS in eyes with early or intermediate AMD. If replicated in future longitudinal studies, the choriocapillaris FD may prove to be a useful parameter for evaluating the functional status and prognosis of these eyes.
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Affiliation(s)
- Marco Nassisi
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, USA; Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Tudor Tepelus
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, USA; Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Giulia Corradetti
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, USA; Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Srinivas R Sadda
- Doheny Image Reading Center, Doheny Eye Institute, Los Angeles, California, USA; Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA.
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Function of cone and cone-related pathways in Ca V1.4 IT mice. Sci Rep 2021; 11:2732. [PMID: 33526839 PMCID: PMC7851161 DOI: 10.1038/s41598-021-82210-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 01/11/2021] [Indexed: 11/09/2022] Open
Abstract
CaV1.4 L-type calcium channels are predominantly expressed in photoreceptor terminals playing a crucial role for synaptic transmission and, consequently, for vision. Human mutations in the encoding gene are associated with congenital stationary night blindness type-2. Besides rod-driven scotopic vision also cone-driven photopic responses are severely affected in patients. The present study therefore examined functional and morphological changes in cones and cone-related pathways in mice carrying the CaV1.4 gain-of function mutation I756T (CaV1.4-IT) using multielectrode array, patch-clamp and immunohistochemical analyses. CaV1.4-IT ganglion cell responses to photopic stimuli were seen only in a small fraction of cells indicative of a major impairment in the cone pathway. Though cone photoreceptors underwent morphological rearrangements, they retained their ability to release glutamate. Our functional data suggested a postsynaptic cone bipolar cell defect, supported by the fact that the majority of cone bipolar cells showed sprouting, while horizontal cells maintained contacts with cones and cone-to-horizontal cell input was preserved. Furthermore a reduction of basal Ca2+ influx by a calcium channel blocker was not sufficient to rescue synaptic transmission deficits caused by the CaV1.4-IT mutation. Long term treatments with low-dose Ca2+ channel blockers might however be beneficial reducing Ca2+ toxicity without major effects on ganglion cells responses.
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A Novel Splice-Site Variant in CACNA1F Causes a Phenotype Synonymous with Åland Island Eye Disease and Incomplete Congenital Stationary Night Blindness. Genes (Basel) 2021; 12:genes12020171. [PMID: 33513752 PMCID: PMC7911795 DOI: 10.3390/genes12020171] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND CACNA1F-related disorders encompass progressive and non-progressive disorders, including Åland island eye disease and incomplete congenital stationary night blindness. These two X-linked disorders are characterized by nystagmus, color vision defect, myopia, and electroretinography (ERG) abnormalities. Ocular hypopigmentation and iris transillumination are reported only in patients with Åland island eye disease. Around 260 variants were reported to be associated with these two non-progressive disorders, with 19 specific to Åland island eye disease and 14 associated with both Åland island eye disease and incomplete congenital stationary night blindness. CACNA1F variants spread on the gene and further analysis are needed to reveal phenotype-genotype correlation. CASE REPORT A complete ocular exam and genetic testing were performed on a 13-year-old boy. A novel splice-site variant, c.4294-11C>G in intron 36 in CACNA1F, was identified at hemizygous state in the patient and at heterozygous state in his asymptomatic mother and explained the phenotype synonymous with Åland island eye disease and incomplete congenital stationary night blindness observed in the patient. CONCLUSION We present a novel variant in the CACNA1F gene causing phenotypic and electrophysiologic findings indistinguishable from those of AIED/CSNB2A disease. This finding further expands the mutational spectrum and our knowledge of CACNA1F-related disease.
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Korecki AJ, Cueva-Vargas JL, Fornes O, Agostinone J, Farkas RA, Hickmott JW, Lam SL, Mathelier A, Zhou M, Wasserman WW, Di Polo A, Simpson EM. Human MiniPromoters for ocular-rAAV expression in ON bipolar, cone, corneal, endothelial, Müller glial, and PAX6 cells. Gene Ther 2021; 28:351-372. [PMID: 33531684 PMCID: PMC8222000 DOI: 10.1038/s41434-021-00227-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/17/2020] [Accepted: 01/15/2021] [Indexed: 02/06/2023]
Abstract
Small and cell-type restricted promoters are important tools for basic and preclinical research, and clinical delivery of gene therapies. In clinical gene therapy, ophthalmic trials have been leading the field, with over 50% of ocular clinical trials using promoters that restrict expression based on cell type. Here, 19 human DNA MiniPromoters were bioinformatically designed for rAAV, tested by neonatal intravenous delivery in mouse, and successful MiniPromoters went on to be tested by intravitreal, subretinal, intrastromal, and/or intravenous delivery in adult mouse. We present promoter development as an overview for each cell type, but only show results in detail for the recommended MiniPromoters: Ple265 and Ple341 (PCP2) ON bipolar, Ple349 (PDE6H) cone, Ple253 (PITX3) corneal stroma, Ple32 (CLDN5) endothelial cells of the blood-retina barrier, Ple316 (NR2E1) Müller glia, and Ple331 (PAX6) PAX6 positive. Overall, we present a resource of new, redesigned, and improved MiniPromoters for ocular gene therapy that range in size from 784 to 2484 bp, and from weaker, equal, or stronger in strength relative to the ubiquitous control promoter smCBA. All MiniPromoters will be useful for therapies involving small regulatory RNA and DNA, and proteins ranging from 517 to 1084 amino acids, representing 62.9-90.2% of human proteins.
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Affiliation(s)
- Andrea J. Korecki
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Jorge L. Cueva-Vargas
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Oriol Fornes
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Jessica Agostinone
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Rachelle A. Farkas
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Jack W. Hickmott
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Siu Ling Lam
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Anthony Mathelier
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Michelle Zhou
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada
| | - Wyeth W. Wasserman
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
| | - Adriana Di Polo
- grid.14848.310000 0001 2292 3357Department of Neuroscience, University of Montreal Hospital Research Centre, University of Montreal, Montreal, QC Canada
| | - Elizabeth M. Simpson
- grid.17091.3e0000 0001 2288 9830Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, BC Canada ,grid.17091.3e0000 0001 2288 9830Department of Medical Genetics, University of British Columbia, Vancouver, BC Canada
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New Omics-Derived Perspectives on Retinal Dystrophies: Could Ion Channels-Encoding or Related Genes Act as Modifier of Pathological Phenotype? Int J Mol Sci 2020; 22:ijms22010070. [PMID: 33374679 PMCID: PMC7793472 DOI: 10.3390/ijms22010070] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/15/2020] [Accepted: 12/21/2020] [Indexed: 02/07/2023] Open
Abstract
Ion channels are membrane-spanning integral proteins expressed in multiple organs, including the eye. Here, ion channels play a role in several 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 a wide spectrum of ocular diseases collectively called channelopathies, a subgroup of inherited retinal dystrophies. Such mutations result in either a loss or gain-of channel functions affecting the structure, assembly, trafficking and localization of channel proteins. We investigated the probands of seven Italian and Egyptian families affected by not completely defined forms of inherited retinal dystrophies, by whole exome sequencing (WES) experiments, and found interesting variants in already known causative genes probably able to impair retinal functionalities. However, because such variants did not completely explain the phenotype manifested by each patient, we proceed to further investigate possible related genes carrying mutations that might complement previously found data, based on the common aspect linked to neurotransmission impairments. We found 10 mutated genes whose variants might alter important ligand binding sites differently distributed through all considered patients. Such genes encode for ion channels, or their regulatory proteins, and strictly interact with known causative genes, also sharing with them synaptic-related pathways. Taking into account several limitations that will be resolved by further experiments, we believe that our exploratory investigation will help scientists to provide a new promising paradigm for precise diagnosis of retinal dystrophies to facilitate the development of rational treatments.
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Gregory KJ, Goudet C. International Union of Basic and Clinical Pharmacology. CXI. Pharmacology, Signaling, and Physiology of Metabotropic Glutamate Receptors. Pharmacol Rev 2020; 73:521-569. [PMID: 33361406 DOI: 10.1124/pr.119.019133] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Metabotropic glutamate (mGlu) receptors respond to glutamate, the major excitatory neurotransmitter in the mammalian brain, mediating a modulatory role that is critical for higher-order brain functions such as learning and memory. Since the first mGlu receptor was cloned in 1992, eight subtypes have been identified along with many isoforms and splice variants. The mGlu receptors are transmembrane-spanning proteins belonging to the class C G protein-coupled receptor family and represent attractive targets for a multitude of central nervous system disorders. Concerted drug discovery efforts over the past three decades have yielded a wealth of pharmacological tools including subtype-selective agents that competitively block or mimic the actions of glutamate or act allosterically via distinct sites to enhance or inhibit receptor activity. Herein, we review the physiologic and pathophysiological roles for individual mGlu receptor subtypes including the pleiotropic nature of intracellular signal transduction arising from each. We provide a comprehensive analysis of the in vitro and in vivo pharmacological properties of prototypical and commercially available orthosteric agonists and antagonists as well as allosteric modulators, including ligands that have entered clinical trials. Finally, we highlight emerging areas of research that hold promise to facilitate rational design of highly selective mGlu receptor-targeting therapeutics in the future. SIGNIFICANCE STATEMENT: The metabotropic glutamate receptors are attractive therapeutic targets for a range of psychiatric and neurological disorders. Over the past three decades, intense discovery efforts have yielded diverse pharmacological tools acting either competitively or allosterically, which have enabled dissection of fundamental biological process modulated by metabotropic glutamate receptors and established proof of concept for many therapeutic indications. We review metabotropic glutamate receptor molecular pharmacology and highlight emerging areas that are offering new avenues to selectively modulate neurotransmission.
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Affiliation(s)
- Karen J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
| | - Cyril Goudet
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
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Galindo-Bocero J, Macías-Franco S, García-González N, Valles-Antuña C, Hernando Acero I, Rozas-Reyes P. Diagnosis of an X-linked type 2 congenital stationary night blindness using electroretinography and CACNA1F sequencing. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2020; 95:607-610. [PMID: 32680768 DOI: 10.1016/j.oftal.2020.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/31/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
A 4-year-old boy, with no history of relevance, presented with bilateral visual impairment, more so in scotopic conditions, and did not improve with optical correction. No significant funduscopic abnormalities were seen, leading to a suspicion of retinal dystrophy. Sequencing of the CACNA1F gene detected the c.3081C>A (p.Tyr1027Ter) mutation, which had occurred de novo in the patient's mother. This mutation, in the aforementioned clinical context, and with a compatible electronegative pattern, establishes the diagnosis of X-linked type 2 congenital stationary night blindness. Electrophysiology and genetic testing should be part of the diagnostic protocol for any unexplained loss of vision in children. The description, nomenclature and classification of hereditary retinal dystrophies based on their genotypic and electroretinograpic characteristics, avoids diagnostic errors due to their usual clinical and phenotypic overlap.
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Affiliation(s)
- J Galindo-Bocero
- Servicio de Oftalmología, Fundación Hospital de Jove, Gijón, Asturias, España.
| | - S Macías-Franco
- Servicio de Oftalmología, Hospital Universitario Central de Asturias, Oviedo, Asturias, España
| | - N García-González
- Unidad de Genética, Área de Gestión Clínica de Pediatría, Hospital Universitario Central de Asturias, Oviedo, Asturias, España
| | - C Valles-Antuña
- Servicio de Neurofisiología Clínica, Hospital Universitario Central de Asturias, Oviedo, Asturias, España
| | - I Hernando Acero
- Unidad de Genética, Área de Gestión Clínica de Pediatría, Hospital Universitario Central de Asturias, Oviedo, Asturias, España
| | - P Rozas-Reyes
- Servicio de Oftalmología, Hospital Universitario Central de Asturias, Oviedo, Asturias, España
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Rai D, Akagi T, Shimohata A, Ishii T, Gangi M, Maruyama T, Wada-Kiyama Y, Ogiwara I, Kaneda M. Involvement of the C-terminal domain in cell surface localization and G-protein coupling of mGluR6. J Neurochem 2020; 158:837-848. [PMID: 33067823 DOI: 10.1111/jnc.15217] [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] [Received: 09/27/2020] [Revised: 05/25/2020] [Accepted: 10/11/2020] [Indexed: 01/05/2023]
Abstract
Metabotropic glutamate receptor 6, mGluR6, interacts with scaffold proteins and Gβγ subunits via its intracellular C-terminal domain (CTD). The mGluR6 pathway is critically involved in the retinal processing of visual signals. We herein investigated whether the CTD (residues 840-871) was necessary for mGluR6 cell surface localization and G-protein coupling using mGluR6-CTD mutants with immunocytochemistry, surface biotinylation assays, and electrophysiological approaches. We used 293T cells and primary hippocampal neurons as model systems. We examined C-terminally truncated mGluR6 and showed that the removal of up to residue 858 did not affect surface localization or glutamate-induced G-protein-mediated responses, whereas a 15-amino acid deletion (Δ857-871) impaired these functions. However, a 21-amino acid deletion (Δ851-871) restored surface localization and glutamate-dependent responses, which were again attenuated when the entire CTD was removed. The sequence alignment of group III mGluRs showed conserved amino acids resembling an ER retention motif in the CTD. These results suggest that the intracellular CTD is required for the cell surface transportation and receptor function of mGluR6, whereas it may contain regulatory elements for intracellular trafficking and signaling.
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Affiliation(s)
- Dilip Rai
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Takumi Akagi
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | | | - Toshiyuki Ishii
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Mie Gangi
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Takuma Maruyama
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | | | - Ikuo Ogiwara
- Department of Physiology, Nippon Medical School, Tokyo, Japan
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Hayashi T, Mizobuchi K, Kikuchi S, Nakano T. Novel biallelic TRPM1 variants in an elderly patient with complete congenital stationary night blindness. Doc Ophthalmol 2020; 142:265-273. [PMID: 33068213 DOI: 10.1007/s10633-020-09798-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/01/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Little is known about whether patients with complete congenital stationary night blindness (CSNB) maintain visual function throughout their lifetime. The purpose of this report was to describe clinical and genetic features of an elderly female patient with complete CSNB that we followed for 5 years. METHODS Molecular genetic analysis using whole-exome sequencing (WES) was performed to detect disease-causing variants. We performed a comprehensive ophthalmic examination including full-field electroretinography (ERG). RESULTS In the patient, WES identified two novel variants (c.1034delT; p.Phe345SerfsTer16 and c.1880T>A; p.Met627Lys) in the TRPM1 gene. Her unaffected daughter has one of the variants. The patient reported that her visual acuity has remained unchanged since elementary school. At the age of 68 years old, fundus and fundus autofluorescence imaging showed no remarkable findings except for mild myopic changes. Goldmann perimetry showed preserved visual fields with all V-4e, I-4e, I-3e and I-2e isopters. Optical coherence tomography demonstrated preserved retinal thickness and lamination. Rod ERG showed no response; bright-flash ERG showed an electronegative configuration with minimally reduced a-waves, and cone and 30-Hz flicker ERG showed minimally reduced responses. Overall, the ERG findings of ON bipolar pathway dysfunction were consistent with complete CSNB. CONCLUSIONS This is the oldest reported patient with complete CSNB and biallelic TRPM1 variants. Our ophthalmic findings suggest that some patients with TRPM1-related CSNB may exhibit preserved retinal function later in life.
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Affiliation(s)
- Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, 105-8461, Japan. .,Department of Ophthalmology, Katsushika Medical Center, The Jikei University School of Medicine, 6-41-2 Aoto, Katsushika-ku, Tokyo, 125-8506, Japan.
| | - Kei Mizobuchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
| | - Shinsuke Kikuchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, 105-8461, Japan.,Kikuchi Eye Clinic, Tokyo, 192-0904, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
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Waldner DM, Ito K, Chen LL, Nguyen L, Chow RL, Lee A, Rancourt DE, Tremblay F, Stell WK, Bech-Hansen NT. Transgenic Expression of Cacna1f Rescues Vision and Retinal Morphology in a Mouse Model of Congenital Stationary Night Blindness 2A (CSNB2A). Transl Vis Sci Technol 2020; 9:19. [PMID: 33117610 PMCID: PMC7571326 DOI: 10.1167/tvst.9.11.19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/17/2020] [Indexed: 12/20/2022] Open
Abstract
Purpose Congenital stationary night blindness 2A (CSNB2A) is a genetic retinal disorder characterized by poor visual acuity, nystagmus, strabismus, and other signs of retinal dysfunction resulting from mutations in Cacna1f -the gene coding for the pore-forming subunit of the calcium channel CaV1.4. Mouse models of CSNB2A have shown that mutations causing the disease deleteriously affect photoreceptors and their synapses with second-order neurons. This study was undertaken to evaluate whether transgenic expression of Cacna1f could rescue morphology and visual function in a Cacna1f-KO model of CSNB2A. Methods Strategic creation, breeding and use of transgenic mouse lines allowed for Cre-driven retina-specific expression of Cacna1f in a CSNB2A model. Transgene expression and retinal morphology were investigated with immunohistochemistry in retinal wholemounts or cross-sections. Visual function was assessed by optokinetic response (OKR) analysis and electroretinography (ERG). Results Mosaic, prenatal expression of Cacna1f in the otherwise Cacna1f-KO retina was sufficient to rescue some visual function. Immunohistochemical analyses demonstrated wild-type-like photoreceptor and synaptic morphology in sections with transgenic expression of Cacna1f. Conclusions This report describes a novel system for Cre-inducible expression of Cacna1f in a Cacna1f-KO mouse model of CSNB2A and provides preclinical evidence for the potential use of gene therapy in the treatment of CSNB2A. Translational Relevance These data have relevance in the treatment of CSNB2A and in understanding how photoreceptor integration might be achieved in retinas in which photoreceptors have been lost, such as retinitis pigmentosa, age-related macular degeneration, and other degenerative conditions.
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Affiliation(s)
- Derek M Waldner
- Graduate Department of Neuroscience, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kenichi Ito
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Li-Li Chen
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Lisa Nguyen
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Robert L Chow
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, Department of Otolaryngology Head-Neck Surgery and Department of Neurology, University of Iowa, Iowa City, IA, USA
| | - Derrick E Rancourt
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Francois Tremblay
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, and Clinical Vision Sciences Program, Faculty of Health Dalhousie University, NS, Canada
| | - William K Stell
- Department of Cell Biology and Anatomy and Department of Surgery, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - N Torben Bech-Hansen
- Department of Medical Genetics, and Department of Surgery, Alberta Children's Hospital Research Institute, and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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Abstract
Inherited retinal diseases (IRD) are a leading cause of blindness in the working age population. The advances in ocular genetics, retinal imaging and molecular biology, have conspired to create the ideal environment for establishing treatments for IRD, with the first approved gene therapy and the commencement of multiple therapy trials. The scope of this review is to familiarize clinicians and scientists with the current landscape of retinal imaging in IRD. Herein we present in a comprehensive and concise manner the imaging findings of: (I) macular dystrophies (MD) [Stargardt disease (ABCA4), X-linked retinoschisis (RS1), Best disease (BEST1), pattern dystrophy (PRPH2), Sorsby fundus dystrophy (TIMP3), and autosomal dominant drusen (EFEMP1)], (II) cone and cone-rod dystrophies (GUCA1A, PRPH2, ABCA4 and RPGR), (III) cone dysfunction syndromes [achromatopsia (CNGA3, CNGB3, PDE6C, PDE6H, GNAT2, ATF6], blue-cone monochromatism (OPN1LW/OPN1MW array), oligocone trichromacy, bradyopsia (RGS9/R9AP) and Bornholm eye disease (OPN1LW/OPN1MW), (IV) Leber congenital amaurosis (GUCY2D, CEP290, CRB1, RDH12, RPE65, TULP1, AIPL1 and NMNAT1), (V) rod-cone dystrophies [retinitis pigmentosa, enhanced S-Cone syndrome (NR2E3), Bietti crystalline corneoretinal dystrophy (CYP4V2)], (VI) rod dysfunction syndromes (congenital stationary night blindness, fundus albipunctatus (RDH5), Oguchi disease (SAG, GRK1), and (VII) chorioretinal dystrophies [choroideremia (CHM), gyrate atrophy (OAT)].
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Affiliation(s)
- Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Kaoru Fujinami
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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125
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Kubatova N, Mao J, Eckert CE, Saxena K, Gande SL, Wachtveitl J, Glaubitz C, Schwalbe H. Light Dynamics of the Retinal-Disease-Relevant G90D Bovine Rhodopsin Mutant. Angew Chem Int Ed Engl 2020; 59:15656-15664. [PMID: 32602600 PMCID: PMC7496284 DOI: 10.1002/anie.202003671] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/25/2020] [Indexed: 12/11/2022]
Abstract
The RHO gene encodes the G-protein-coupled receptor (GPCR) rhodopsin. Numerous mutations associated with impaired visual cycle have been reported; the G90D mutation leads to a constitutively active mutant form of rhodopsin that causes CSNB disease. We report on the structural investigation of the retinal configuration and conformation in the binding pocket in the dark and light-activated state by solution and MAS-NMR spectroscopy. We found two long-lived dark states for the G90D mutant with the 11-cis retinal bound as Schiff base in both populations. The second minor population in the dark state is attributed to a slight shift in conformation of the covalently bound 11-cis retinal caused by the mutation-induced distortion on the salt bridge formation in the binding pocket. Time-resolved UV/Vis spectroscopy was used to monitor the functional dynamics of the G90D mutant rhodopsin for all relevant time scales of the photocycle. The G90D mutant retains its conformational heterogeneity during the photocycle.
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Affiliation(s)
- Nina Kubatova
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute for Organic Chemistry and Chemical BiologyGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
| | - Jiafei Mao
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute of Biophysical ChemistryGoethe University FrankfurtMax-von-Laue-Strasse 960438FrankfurtGermany
| | - Carl Elias Eckert
- Institute of Physical and Theoretical ChemistryGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
| | - Krishna Saxena
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute for Organic Chemistry and Chemical BiologyGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
| | - Santosh L. Gande
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute for Organic Chemistry and Chemical BiologyGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
| | - Josef Wachtveitl
- Institute of Physical and Theoretical ChemistryGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
| | - Clemens Glaubitz
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute of Biophysical ChemistryGoethe University FrankfurtMax-von-Laue-Strasse 960438FrankfurtGermany
| | - Harald Schwalbe
- Center for Biomolecular Magnetic ResonanceGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
- Institute for Organic Chemistry and Chemical BiologyGoethe University FrankfurtMax-von-Laue-Strasse 760438FrankfurtGermany
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Sallah SR, Sergouniotis PI, Barton S, Ramsden S, Taylor RL, Safadi A, Kabir M, Ellingford JM, Lench N, Lovell SC, Black GCM. Using an integrative machine learning approach utilising homology modelling to clinically interpret genetic variants: CACNA1F as an exemplar. Eur J Hum Genet 2020; 28:1274-1282. [PMID: 32313206 PMCID: PMC7608274 DOI: 10.1038/s41431-020-0623-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 01/13/2020] [Accepted: 03/10/2020] [Indexed: 02/04/2023] Open
Abstract
Advances in DNA sequencing technologies have revolutionised rare disease diagnostics and have led to a dramatic increase in the volume of available genomic data. A key challenge that needs to be overcome to realise the full potential of these technologies is that of precisely predicting the effect of genetic variants on molecular and organismal phenotypes. Notably, despite recent progress, there is still a lack of robust in silico tools that accurately assign clinical significance to variants. Genetic alterations in the CACNA1F gene are the commonest cause of X-linked incomplete Congenital Stationary Night Blindness (iCSNB), a condition associated with non-progressive visual impairment. We combined genetic and homology modelling data to produce CACNA1F-vp, an in silico model that differentiates disease-implicated from benign missense CACNA1F changes. CACNA1F-vp predicts variant effects on the structure of the CACNA1F encoded protein (a calcium channel) using parameters based upon changes in amino acid properties; these include size, charge, hydrophobicity, and position. The model produces an overall score for each variant that can be used to predict its pathogenicity. CACNA1F-vp outperformed four other tools in identifying disease-implicated variants (area under receiver operating characteristic and precision recall curves = 0.84; Matthews correlation coefficient = 0.52) using a tenfold cross-validation technique. We consider this protein-specific model to be a robust stand-alone diagnostic classifier that could be replicated in other proteins and could enable precise and timely diagnosis.
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Affiliation(s)
- Shalaw R Sallah
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK.
| | - Panagiotis I Sergouniotis
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
| | - Stephanie Barton
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
| | - Simon Ramsden
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
| | - Rachel L Taylor
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
| | - Amro Safadi
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Mitra Kabir
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Jamie M Ellingford
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
| | - Nick Lench
- Congenica Ltd, Biodata Innovation Centre, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Simon C Lovell
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Graeme C M Black
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicines and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
- Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Sciences Centre, St Mary's Hospital, Manchester, UK
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127
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De Silva SR, Arno G, Robson AG, Fakin A, Pontikos N, Mohamed MD, Bird AC, Moore AT, Michaelides M, Webster AR, Mahroo OA. The X-linked retinopathies: Physiological insights, pathogenic mechanisms, phenotypic features and novel therapies. Prog Retin Eye Res 2020; 82:100898. [PMID: 32860923 DOI: 10.1016/j.preteyeres.2020.100898] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/07/2020] [Accepted: 08/21/2020] [Indexed: 02/08/2023]
Abstract
X-linked retinopathies represent a significant proportion of monogenic retinal disease. They include progressive and stationary conditions, with and without syndromic features. Many are X-linked recessive, but several exhibit a phenotype in female carriers, which can help establish diagnosis and yield insights into disease mechanisms. The presence of affected carriers can misleadingly suggest autosomal dominant inheritance. Some disorders (such as RPGR-associated retinopathy) show diverse phenotypes from variants in the same gene and also highlight limitations of current genetic sequencing methods. X-linked disease frequently arises from loss of function, implying potential for benefit from gene replacement strategies. We review X-inactivation and X-linked inheritance, and explore burden of disease attributable to X-linked genes in our clinically and genetically characterised retinal disease cohort, finding correlation between gene transcript length and numbers of families. We list relevant genes and discuss key clinical features, disease mechanisms, carrier phenotypes and novel experimental therapies. We consider in detail the following: RPGR (associated with retinitis pigmentosa, cone and cone-rod dystrophy), RP2 (retinitis pigmentosa), CHM (choroideremia), RS1 (X-linked retinoschisis), NYX (complete congenital stationary night blindness (CSNB)), CACNA1F (incomplete CSNB), OPN1LW/OPN1MW (blue cone monochromacy, Bornholm eye disease, cone dystrophy), GPR143 (ocular albinism), COL4A5 (Alport syndrome), and NDP (Norrie disease and X-linked familial exudative vitreoretinopathy (FEVR)). We use a recently published transcriptome analysis to explore expression by cell-type and discuss insights from electrophysiology. In the final section, we present an algorithm for genes to consider in diagnosing males with non-syndromic X-linked retinopathy, summarise current experimental therapeutic approaches, and consider questions for future research.
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Affiliation(s)
- Samantha R De Silva
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Gavin Arno
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony G Robson
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Ana Fakin
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Ljubljana University Medical Centre, Ljubljana, Slovenia
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Moin D Mohamed
- Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK
| | - Alan C Bird
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, UCSF School of Medicine, San Francisco, CA, USA
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Andrew R Webster
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Omar A Mahroo
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK; Section of Ophthalmology, King's College London, UK; Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.
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128
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Kubatova N, Mao J, Eckert CE, Saxena K, Gande SL, Wachtveitl J, Glaubitz C, Schwalbe H. Light Dynamics of the Retinal‐Disease‐Relevant G90D Bovine Rhodopsin Mutant. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003671] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Nina Kubatova
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute for Organic Chemistry and Chemical Biology Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
| | - Jiafei Mao
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute of Biophysical Chemistry Goethe University Frankfurt Max-von-Laue-Strasse 9 60438 Frankfurt Germany
| | - Carl Elias Eckert
- Institute of Physical and Theoretical Chemistry Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
| | - Krishna Saxena
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute for Organic Chemistry and Chemical Biology Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
| | - Santosh L. Gande
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute for Organic Chemistry and Chemical Biology Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
| | - Josef Wachtveitl
- Institute of Physical and Theoretical Chemistry Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
| | - Clemens Glaubitz
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute of Biophysical Chemistry Goethe University Frankfurt Max-von-Laue-Strasse 9 60438 Frankfurt Germany
| | - Harald Schwalbe
- Center for Biomolecular Magnetic Resonance Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
- Institute for Organic Chemistry and Chemical Biology Goethe University Frankfurt Max-von-Laue-Strasse 7 60438 Frankfurt Germany
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129
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Abstract
Horses perform in a variety of disciplines that are visually demanding, and any disease impacting the eye has the potential to threaten vision and thus the utility of the horse. Advances in equine genetics have enabled the understanding of some inherited ocular disorders and ocular manifestations and are enabling cross-species comparisons. Genetic testing for multiple congenital ocular anomalies, congenital stationary night blindness, equine recurrent uveitis, and squamous cell carcinoma can identify horses with or at risk for disease and thus can assist in clinical management and breeding decisions. This article describes the current knowledge of inherited ocular disorders.
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Affiliation(s)
- Rebecca R Bellone
- Department of Population Health and Reproduction, Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
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130
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Di Scipio M, Tavares E, Deshmukh S, Audo I, Green-Sanderson K, Zubak Y, Zine-Eddine F, Pearson A, Vig A, Tang CY, Mollica A, Karas J, Tumber A, Yu CW, Billingsley G, Wilson MD, Zeitz C, Héon E, Vincent A. Phenotype Driven Analysis of Whole Genome Sequencing Identifies Deep Intronic Variants that Cause Retinal Dystrophies by Aberrant Exonization. Invest Ophthalmol Vis Sci 2020; 61:36. [PMID: 32881472 PMCID: PMC7443117 DOI: 10.1167/iovs.61.10.36] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/16/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To demonstrate the effectiveness of combining retinal phenotyping and focused variant filtering from genome sequencing (GS) in identifying deep intronic disease causing variants in inherited retinal dystrophies. Methods Affected members from three pedigrees with classical enhanced S-cone syndrome (ESCS; Pedigree 1), congenital stationary night blindness (CSNB; Pedigree 2), and achromatopsia (ACHM; Pedigree 3), respectively, underwent detailed ophthalmologic evaluation, optical coherence tomography, and electroretinography. The probands underwent panel-based genetic testing followed by GS analysis. Minigene constructs (NR2E3, GPR179 and CNGB3) and patient-derived cDNA experiments (NR2E3 and GPR179) were performed to assess the functional effect of the deep intronic variants. Results The electrophysiological findings confirmed the clinical diagnosis of ESCS, CSNB, and ACHM in the respective pedigrees. Panel-based testing revealed heterozygous pathogenic variants in NR2E3 (NM_014249.3; c.119-2A>C; Pedigree 1) and CNGB3 (NM_019098.4; c.1148delC/p.Thr383Ilefs*13; Pedigree 3). The GS revealed heterozygous deep intronic variants in Pedigrees 1 (NR2E3; c.1100+1124G>A) and 3 (CNGB3; c.852+4751A>T), and a homozygous GPR179 variant in Pedigree 2 (NM_001004334.3; c.903+343G>A). The identified variants segregated with the phenotype in all pedigrees. All deep intronic variants were predicted to generate a splice acceptor gain causing aberrant exonization in NR2E3 [89 base pairs (bp)], GPR179 (197 bp), and CNGB3 (73 bp); splicing defects were validated through patient-derived cDNA experiments and/or minigene constructs and rescued by antisense oligonucleotide treatment. Conclusions Deep intronic mutations contribute to missing heritability in retinal dystrophies. Combining results from phenotype-directed gene panel testing, GS, and in silico splice prediction tools can help identify these difficult-to-detect pathogenic deep intronic variants.
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Affiliation(s)
- Matteo Di Scipio
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Erika Tavares
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Shriya Deshmukh
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC1423, Paris, France
- University College London Institute of Ophthalmology, London, United Kingdom
| | - Kit Green-Sanderson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Yuliya Zubak
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Fayçal Zine-Eddine
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Alexander Pearson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anjali Vig
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Chen Yu Tang
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Antonio Mollica
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Jonathan Karas
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anupreet Tumber
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | - Caberry W. Yu
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Gail Billingsley
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Michael D. Wilson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Elise Héon
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
| | - Ajoy Vincent
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
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131
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Agosto MA, Wensel TG. LRRTM4 is a member of the transsynaptic complex between rod photoreceptors and bipolar cells. J Comp Neurol 2020; 529:221-233. [PMID: 32390181 DOI: 10.1002/cne.24944] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 04/09/2020] [Accepted: 05/01/2020] [Indexed: 12/22/2022]
Abstract
Leucine rich repeat transmembrane (LRRTM) proteins are synaptic adhesion molecules with roles in synapse formation and signaling. LRRTM4 transcripts were previously shown to be enriched in rod bipolar cells (BCs), secondary neurons of the retina that form synapses with rod photoreceptors. Using two different antibodies, LRRTM4 was found to reside primarily at rod BC dendritic tips, where it colocalized with the transduction channel protein, TRPM1. LRRTM4 was not detected at dendritic tips of ON-cone BCs. Following somatic knockout of LRRTM4 in BCs by subretinal injection and electroporation of CRISPR/Cas9, LRRTM4 was abolished or reduced in the dendritic tips of transfected cells. Knockout cells had a normal complement of TRPM1 at their dendritic tips, while GPR179 accumulation was partially reduced. In experiments with heterologously expressed protein, the extracellular domain of LRRTM4 was found to engage in heparan-sulfate dependent binding with pikachurin. These results implicate LRRTM4 in the GPR179-pikachurin-dystroglycan transsynaptic complex at rod synapses.
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Affiliation(s)
- Melina A Agosto
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Theodore G Wensel
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
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132
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Senapati S, Park PSH. Differential adaptations in rod outer segment disc membranes in different models of congenital stationary night blindness. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183396. [PMID: 32533975 DOI: 10.1016/j.bbamem.2020.183396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 04/01/2020] [Accepted: 06/08/2020] [Indexed: 01/20/2023]
Abstract
Rod photoreceptor cells initiate scotopic vision when the light receptor rhodopsin absorbs a photon of light to initiate phototransduction. These photoreceptor cells are exquisitely sensitive and have adaptive mechanisms in place to maintain optimal function and to overcome dysfunctional states. One adaptation rod photoreceptor cells exhibit is in the packing properties of rhodopsin within the membrane. The mechanism underlying these adaptations is unclear. Mouse models of congenital stationary night blindness with different molecular causes were investigated to determine which signals are important for adaptations in rod photoreceptor cells. Night blindness in these mice is caused by dysfunction in either rod photoreceptor cell signaling or bipolar cell signaling. Changes in the packing of rhodopsin within photoreceptor cell membranes were examined by atomic force microscopy. Mice expressing constitutively active rhodopsin did not exhibit any adaptations, even under constant dark conditions. Mice with disrupted bipolar cell signaling exhibited adaptations, however, they were distinct from those in mice with disrupted phototransduction. These differential adaptations demonstrate that although multiple molecular defects can lead to a similar primary defect causing disease (i.e., night blindness), they can cause different secondary effects (i.e., adaptations). The lighting environment or signaling defects present from birth and during early rearing can condition mice and affect the adaptations occurring in more mature animals. A comparison of effects in wild-type mice, mice with defective phototransduction, and mice with defective bipolar cell signaling, indicated that bipolar cell signaling plays a role in this conditioning but is not required for adaptations in more mature animals.
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Affiliation(s)
- Subhadip Senapati
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Paul S-H Park
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, OH 44106, USA.
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Mechaussier S, Almoallem B, Zeitz C, Van Schil K, Jeddawi L, Van Dorpe J, Dueñas Rey A, Condroyer C, Pelle O, Polak M, Boddaert N, Bahi-Buisson N, Cavallin M, Bacquet JL, Mouallem-Bézière A, Zambrowski O, Sahel JA, Audo I, Kaplan J, Rozet JM, De Baere E, Perrault I. Loss of Function of RIMS2 Causes a Syndromic Congenital Cone-Rod Synaptic Disease with Neurodevelopmental and Pancreatic Involvement. Am J Hum Genet 2020; 106:859-871. [PMID: 32470375 PMCID: PMC7273530 DOI: 10.1016/j.ajhg.2020.04.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 04/29/2020] [Indexed: 12/13/2022] Open
Abstract
Congenital cone-rod synaptic disorder (CRSD), also known as incomplete congenital stationary night blindness (iCSNB), is a non-progressive inherited retinal disease (IRD) characterized by night blindness, photophobia, and nystagmus, and distinctive electroretinographic features. Here, we report bi-allelic RIMS2 variants in seven CRSD-affected individuals from four unrelated families. Apart from CRSD, neurodevelopmental disease was observed in all affected individuals, and abnormal glucose homeostasis was observed in the eldest affected individual. RIMS2 regulates synaptic membrane exocytosis. Data mining of human adult bulk and single-cell retinal transcriptional datasets revealed predominant expression in rod photoreceptors, and immunostaining demonstrated RIMS2 localization in the human retinal outer plexiform layer, Purkinje cells, and pancreatic islets. Additionally, nonsense variants were shown to result in truncated RIMS2 and decreased insulin secretion in mammalian cells. The identification of a syndromic stationary congenital IRD has a major impact on the differential diagnosis of syndromic congenital IRD, which has previously been exclusively linked with degenerative IRD.
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Affiliation(s)
- Sabrina Mechaussier
- Laboratory of Genetics in Ophthalmology, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France
| | - Basamat Almoallem
- Center for Medical Genetics and Department of Biomolecular Medicine, Ghent University and Ghent University Hospital, 9000 Ghent, Belgium; Department of Ophthalmology, King Abdul-Aziz University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Christina Zeitz
- Sorbonne Université, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, 75012 Paris, France
| | - Kristof Van Schil
- Center for Medical Genetics and Department of Biomolecular Medicine, Ghent University and Ghent University Hospital, 9000 Ghent, Belgium
| | - Laila Jeddawi
- Pediatric Ophthalmology Division, Dhahran Eye Specialist Hospital, Dhahran 34257, Saudi Arabia
| | - Jo Van Dorpe
- Department of Pathology, Ghent University and Ghent University Hospital, 9000 Ghent, Belgium
| | - Alfredo Dueñas Rey
- Center for Medical Genetics and Department of Biomolecular Medicine, Ghent University and Ghent University Hospital, 9000 Ghent, Belgium
| | - Christel Condroyer
- Sorbonne Université, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, 75012 Paris, France
| | - Olivier Pelle
- Cell Sorting Facility, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France
| | - Michel Polak
- Endocrinology, Gynecology, and Pediatric Diabetology Department, University Hospital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, 75015 Paris, France
| | - Nathalie Boddaert
- Department of Pediatric Radiology, University Hospital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, 75015 Paris, France
| | - Nadia Bahi-Buisson
- Pediatric Neurology Department, University Hospital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, 75015 Paris, France
| | - Mara Cavallin
- Laboratory of Embryology and Genetics of Human Malformation, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France
| | - Jean-Louis Bacquet
- Service d'Ophtalmologie, Centre Hospitalier Intercommunal de Créteil, Assistance Publique-Hôpitaux de Paris, 94000 Créteil, France
| | - Alexandra Mouallem-Bézière
- Service d'Ophtalmologie, Centre Hospitalier Intercommunal de Créteil, Assistance Publique-Hôpitaux de Paris, 94000 Créteil, France
| | - Olivia Zambrowski
- Service d'Ophtalmologie, Centre Hospitalier Intercommunal de Créteil, Assistance Publique-Hôpitaux de Paris, 94000 Créteil, France; Ophthalmology Department, University Hospital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, 75015 Paris, France
| | - José Alain Sahel
- Sorbonne Université, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, 75012 Paris, France; Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, INSERM, Direction de l'Hospitalisation et de l'Organisation des Soins (DHOS), Centres d'Investigations Cliniques (CIC) 1423, 75012 Paris, France; Fondation Ophtalmologique Adolphe de Rothschild, 75019 Paris, France; Académie des Sciences, Institut de France, 75006 Paris, France; Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, PA 15213, USA
| | - Isabelle Audo
- Sorbonne Université, INSERM, Centre National de la Recherche Scientifique, Institut de la Vision, 75012 Paris, France; Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, INSERM, Direction de l'Hospitalisation et de l'Organisation des Soins (DHOS), Centres d'Investigations Cliniques (CIC) 1423, 75012 Paris, France; Institute of Ophthalmology, University College of London, London EC1V 9EL, UK
| | - Josseline Kaplan
- Laboratory of Genetics in Ophthalmology, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France; Service d'Ophtalmologie, Centre Hospitalier Intercommunal de Créteil, Assistance Publique-Hôpitaux de Paris, 94000 Créteil, France
| | - Jean-Michel Rozet
- Laboratory of Genetics in Ophthalmology, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France
| | - Elfride De Baere
- Center for Medical Genetics and Department of Biomolecular Medicine, Ghent University and Ghent University Hospital, 9000 Ghent, Belgium.
| | - Isabelle Perrault
- Laboratory of Genetics in Ophthalmology, INSERM UMR 1163, Institute of Genetic Diseases, Imagine and Paris University, 75015 Paris, France.
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Jiman OA, Taylor RL, Lenassi E, Smith JC, Douzgou S, Ellingford JM, Barton S, Hardcastle C, Fletcher T, Campbell C, Ashworth J, Biswas S, Ramsden SC, Manson FD, Black GC. Diagnostic yield of panel-based genetic testing in syndromic inherited retinal disease. Eur J Hum Genet 2020; 28:576-586. [PMID: 31836858 PMCID: PMC7171123 DOI: 10.1038/s41431-019-0548-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 10/22/2019] [Accepted: 10/29/2019] [Indexed: 01/22/2023] Open
Abstract
Thirty percent of all inherited retinal disease (IRD) is accounted for by conditions with extra-ocular features. This study aimed to establish the genetic diagnostic pick-up rate for IRD patients with one or more extra-ocular features undergoing panel-based screening in a clinical setting. One hundred and six participants, tested on a gene panel which contained both isolated and syndromic IRD genes, were retrospectively ascertained from the Manchester Genomic Diagnostics Laboratory database spanning 6 years (2012-2017). Phenotypic features were extracted from the clinical notes and classified according to Human Phenotype Ontology; all identified genetic variants were interpreted in accordance to the American College of Medical Genetics and Genomics guidelines. Overall, 49% (n = 52) of patients received a probable genetic diagnosis. A further 6% (n = 6) had a single disease-associated variant in an autosomal recessive disease-relevant gene. Fifty-two percent (n = 55) of patients had a clinical diagnosis at the time of testing. Of these, 71% (n = 39) received a probable genetic diagnosis. By contrast, for those without a provisional clinical diagnosis (n = 51), only 25% (n = 13) received a probable genetic diagnosis. The clinical diagnosis of Usher (n = 33) and Bardet-Biedl syndrome (n = 10) was confirmed in 67% (n = 22) and 80% (n = 8), respectively. The testing diagnostic rate in patients with clinically diagnosed multisystemic IRD conditions was significantly higher than those without one (71% versus 25%; p value < 0.001). The lower pick-up rate in patients without a clinical diagnosis suggests that panel-based approaches are unlikely to be the most effective means of achieving a molecular diagnosis for this group. Here, we suggest that genome-wide approaches (whole exome or genome) are more appropriate.
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Affiliation(s)
- Omamah A Jiman
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Rachel L Taylor
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Eva Lenassi
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jill Clayton Smith
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Sofia Douzgou
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jamie M Ellingford
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Stephanie Barton
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Claire Hardcastle
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Tracy Fletcher
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Christopher Campbell
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Jane Ashworth
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Susmito Biswas
- Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - Simon C Ramsden
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK
| | - Forbes D Manson
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK
| | - Graeme C Black
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre (MAHSC), University of Manchester, Manchester, UK.
- Manchester Centre for Genomic Medicine, St Mary's Hospital, Central Manchester University Hospitals NHS Foundation Trust, MAHSC, Manchester, UK.
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135
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Varin J, Reynolds MM, Bouzidi N, Tick S, Wohlschlegel J, Becquart O, Michiels C, Dereure O, Duvoisin RM, Morgans CW, Sahel JA, Samaran Q, Guillot B, Pulido JS, Audo I, Zeitz C. Identification and characterization of novel TRPM1 autoantibodies from serum of patients with melanoma-associated retinopathy. PLoS One 2020; 15:e0231750. [PMID: 32324760 PMCID: PMC7179873 DOI: 10.1371/journal.pone.0231750] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/31/2020] [Indexed: 12/15/2022] Open
Abstract
Melanoma-associated retinopathy (MAR) is a rare paraneoplastic retinal disorder usually occurring in the context of metastatic melanoma. Patients present with night blindness, photopsias and a constriction of the visual field. MAR is an auto-immune disorder characterized by the production of autoantibodies targeting retinal proteins, especially autoantibodies reacting to the cation channel TRPM1 produced in melanocytes and ON-bipolar cells. TRPM1 has at least three different isoforms which vary in the N-terminal region of the protein. In this study, we report the case of three new MAR patients presenting different anti-TRPM1 autoantibodies reacting to the three isoforms of TRPM1 with variable binding affinity. Two sera recognized all isoforms of TRPM1, while one recognized only the two longest isoforms upon immunolocalization studies on overexpressing cells. Similarly, the former two sera reacted with all TRPM1 isoforms on western blot, but an immunoprecipitation enrichment step was necessary to detect all isoforms with the latter serum. In contrast, all sera labelled ON-bipolar cells on Tprm1+/+ but not on Trpm1-/- mouse retina as shown by co-immunolocalization. This confirms that the MAR sera specifically detect TRPM1. Most likely, the anti-TRPM1 autoantibodies of different patients vary in affinity and concentration. In addition, the binding of autoantibodies to TRPM1 may be conformation-dependent, with epitopes being inaccessible in some constructs (truncated polypeptides versus full-length TRPM1) or applications (western blotting versus immunohistochemistry). Therefore, we propose that a combination of different methods should be used to test for the presence of anti-TRPM1 autoantibodies in the sera of MAR patients.
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Affiliation(s)
- Juliette Varin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Margaret M. Reynolds
- Department of Ophthalmology, Washington University, Saint Louis, MO, United States of America
| | - Nassima Bouzidi
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Sarah Tick
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
| | | | - Ondine Becquart
- Department of Dermatology and INSERM U1058 “Pathogenesis and control of chronic infections”, University of Montpellier, Montpellier, France
| | | | - Olivier Dereure
- Department of Dermatology and INSERM U1058 “Pathogenesis and control of chronic infections”, University of Montpellier, Montpellier, France
| | - Robert M. Duvoisin
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, United States of America
| | - Catherine W. Morgans
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, United States of America
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
- Fondation Ophtalmologique Adolphe de Rothschild, Paris, France
- Académie des Sciences, Institut de France, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Quentin Samaran
- Department of Dermatology and INSERM U1058 “Pathogenesis and control of chronic infections”, University of Montpellier, Montpellier, France
| | - Bernard Guillot
- Department of Dermatology and INSERM U1058 “Pathogenesis and control of chronic infections”, University of Montpellier, Montpellier, France
| | - José S. Pulido
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN, United States of America
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
- Institute of Ophthalmology, University College of London, London, United Kingdom
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- * E-mail:
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136
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Alsalamah AK, Khan AO. Electronegative Electroretinograms in the United Arab Emirates. Middle East Afr J Ophthalmol 2020; 27:86-90. [PMID: 32874040 PMCID: PMC7442078 DOI: 10.4103/meajo.meajo_106_20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 11/05/2022] Open
Abstract
PURPOSE An electronegative electroretinogram (ERG), defined as having a b:a wave ratio ≤1 in the scotopic flash ERG response, indicates relative inner retinal dysfunction. Causes vary depending upon the study population. In the Arabian Gulf, where inherited retinal disease is relatively prevalent, common diagnoses associated with electronegative ERGs have not been described. In this study, we report the frequency and causes of electronegative ERGs in a cohort of Emirati patients with inherited retinal disease. METHODS A retrospective review was performed of all full-field ERGs done for Emirati patients in the Ocular Genetics Service of Cleveland Clinic Abu Dhabi from January 2017 to December 2019. Those who had an electronegative ERG in at least one eye were included in the study. RESULTS Out of 137 patients, 9 probands (6.6%) had an electronegative ERG. The mean age at presentation was 24 years (range 5-48 years), and five patients (55.6%) were male. The final clinical diagnoses were congenital stationary night blindness (CSNB) (two TRPM1-related and one Oguchi disease), X-linked retinoschisis (XLRS) (one genetically confirmed and two not genetically tested), cone-rod dystrophy (one CRX-related and one not genetically tested), and enhanced S-cone syndrome (ESCS) (one NRL-related). The one patient who did not have bilateral electronegative ERGs was a male with XLRS whose fellow eye had an unrecordable ERG. CONCLUSIONS In this series of Emirati patients, an electronegative ERG was most commonly associated with the inherited retinal diseases recessive CSNB and XLRS. An electronegative ERG was noted in a case of NRL-related ESCS.
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Affiliation(s)
- Abrar K. Alsalamah
- Vitreoretinal and Uveitis Divisions, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Arif O. Khan
- Eye Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western University, Cleveland, Ohio, USA
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137
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Furukawa T, Ueno A, Omori Y. Molecular mechanisms underlying selective synapse formation of vertebrate retinal photoreceptor cells. Cell Mol Life Sci 2020; 77:1251-1266. [PMID: 31586239 PMCID: PMC11105113 DOI: 10.1007/s00018-019-03324-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 09/21/2019] [Accepted: 09/25/2019] [Indexed: 11/29/2022]
Abstract
In vertebrate central nervous systems (CNSs), highly diverse neurons are selectively connected via synapses, which are essential for building an intricate neural network. The vertebrate retina is part of the CNS and is comprised of a distinct laminar organization, which serves as a good model system to study developmental synapse formation mechanisms. In the retina outer plexiform layer, rods and cones, two types of photoreceptor cells, elaborate selective synaptic contacts with ON- and/or OFF-bipolar cell terminals as well as with horizontal cell terminals. In the mouse retina, three photoreceptor subtypes and at least 15 bipolar subtypes exist. Previous and recent studies have significantly progressed our understanding of how selective synapse formation, between specific subtypes of photoreceptor and bipolar cells, is designed at the molecular level. In the ON pathway, photoreceptor-derived secreted and transmembrane proteins directly interact in trans with the GRM6 (mGluR6) complex, which is localized to ON-bipolar cell dendritic terminals, leading to selective synapse formation. Here, we review our current understanding of the key factors and mechanisms underlying selective synapse formation of photoreceptor cells with bipolar and horizontal cells in the retina. In addition, we describe how defects/mutations of the molecules involved in photoreceptor synapse formation are associated with human retinal diseases and visual disorders.
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Affiliation(s)
- Takahisa Furukawa
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Akiko Ueno
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yoshihiro Omori
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
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138
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Karatsai E, Robson AG, Taylor SRJ. Outcomes Associated With Sustained-Release Intraocular Fluocinolone Implants in a Case of Melanoma-Associated Retinopathy Treated Without Systemic Immunosuppression. JAMA Ophthalmol 2020; 137:564-567. [PMID: 30896772 DOI: 10.1001/jamaophthalmol.2019.0284] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Importance Melanoma-associated retinopathy (MAR) is a paraneoplastic syndrome in which antiretinal antibodies crossreact with retinal ON-bipolar cells, resulting in night blindness and progressive visual field loss. Current therapeutic options include cytoreductive surgery in combination with immunoglobulin, corticosteroids, or plasmapheresis, but their effectiveness is limited and may be contraindicated, given the possible protective role of circulating autoantibodies against metastatic spread. We report 3-year follow-up of the first case (to our knowledge) of MAR treated with intravitreal long-acting steroid implants. Objective To report on a patient with MAR who was treated with intravitreal fluocinolone acetonide implants in the absence of systemic immunosuppression. Design, Setting, and Participants This is a 3-year follow-up of a 73-year-old woman with a history of surgical excision of a malignant melanoma of the left pinna who presented with visual symptoms of shimmering and nyctalopia. Fundus examination, fundus autofluorescence, and optical coherence tomography were normal, with no evidence of cystoid macular edema. Automated perimetry showed a reduction in visual field and full-field electroretinography (ERG) demonstrated findings consistent with generalized ON-bipolar cell dysfunction, typical of MAR. The patient was treated with bilateral fluocinolone acetonide intravitreal implants. Main Outcomes and Measures Visual acuity, visual field, and electroretinography testing for 3 years after treatment. Results Visual fields improved in this 73-year-old patient from 20/30 (Snellen measured as 6/9) OD and 20/16 (6/5) OS at baseline to 20/20 OU within 1 week of treatment. Detailed electroretinography monitoring indicated characteristic abnormalities that partly resolved after treatment, consistent with improved inner retinal ON-bipolar cell function. Bilateral cataracts developed approximately 2 years after injection; cataract surgery was performed uneventfully. At 3 years posttreatment, the patient remained visually stable and in systemic disease remission, with best-corrected visual acuity remaining at 20/20 OU. Conclusions and Relevance We report what is, to our knowledge, the first case of MAR treated with intravitreal slow-release corticosteroid implants, which shows improvements in visual symptoms, visual fields, and retinal function. Sustained-release intraocular steroid implants may offer an effective and safe alternative to systemic immunosuppression in MAR, although results from 1 case should be generalized with abundant caution.
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Affiliation(s)
| | - Anthony G Robson
- Moorfields Eye Hospital, London, United Kingdom.,University College London Institute of Ophthalmology, London, United Kingdom
| | - Simon R J Taylor
- Royal Surrey County Hospital, Guildford, United Kingdom.,University of Surrey, Guildford, United Kingdom
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139
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Metabolic and Redox Signaling of the Nucleoredoxin-Like-1 Gene for the Treatment of Genetic Retinal Diseases. Int J Mol Sci 2020; 21:ijms21051625. [PMID: 32120883 PMCID: PMC7084304 DOI: 10.3390/ijms21051625] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 02/06/2023] Open
Abstract
The loss of cone photoreceptor function in retinitis pigmentosa (RP) severely impacts the central and daily vision and quality of life of patients affected by this disease. The loss of cones follows the degeneration of rods, in a manner independent of the causing mutations in numerous genes associated with RP. We have explored this phenomenon and proposed that the loss of rods triggers a reduction in the expression of rod-derived cone viability factor (RdCVF) encoded by the nucleoredoxin-like 1 (NXNL1) gene which interrupts the metabolic and redox signaling between rods and cones. After providing scientific evidence supporting this mechanism, we propose a way to restore this lost signaling and prevent the cone vision loss in animal models of RP. We also explain how we could restore this signaling to prevent cone vision loss in animal models of the disease and how we plan to apply this therapeutic strategy by the administration of both products of NXNL1 encoding the trophic factor RdCVF and the thioredoxin enzyme RdCVFL using an adeno-associated viral vector. We describe in detail all the steps of this translational program, from the design of the drug, its production, biological validation, and analytical and preclinical qualification required for a future clinical trial that would, if successful, provide a treatment for this incurable disease.
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140
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Shiels A. TRPM3_miR-204: a complex locus for eye development and disease. Hum Genomics 2020; 14:7. [PMID: 32070426 PMCID: PMC7027284 DOI: 10.1186/s40246-020-00258-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 02/06/2020] [Indexed: 02/07/2023] Open
Abstract
First discovered in a light-sensitive retinal mutant of Drosophila, the transient receptor potential (TRP) superfamily of non-selective cation channels serve as polymodal cellular sensors that participate in diverse physiological processes across the animal kingdom including the perception of light, temperature, pressure, and pain. TRPM3 belongs to the melastatin sub-family of TRP channels and has been shown to function as a spontaneous calcium channel, with permeability to other cations influenced by alternative splicing and/or non-canonical channel activity. Activators of TRPM3 channels include the neurosteroid pregnenolone sulfate, calmodulin, phosphoinositides, and heat, whereas inhibitors include certain drugs, plant-derived metabolites, and G-protein subunits. Activation of TRPM3 channels at the cell membrane elicits a signal transduction cascade of mitogen-activated kinases and stimulus response transcription factors. The mammalian TRPM3 gene hosts a non-coding microRNA gene specifying miR-204 that serves as both a tumor suppressor and a negative regulator of post-transcriptional gene expression during eye development in vertebrates. Ocular co-expression of TRPM3 and miR-204 is upregulated by the paired box 6 transcription factor (PAX6) and mutations in all three corresponding genes underlie inherited forms of eye disease in humans including early-onset cataract, retinal dystrophy, and coloboma. This review outlines the genomic and functional complexity of the TRPM3_miR-204 locus in mammalian eye development and disease.
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Affiliation(s)
- Alan Shiels
- Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 S. Euclid Ave., Box 8096, St. Louis, MO, 63110, USA.
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141
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Orozco LD, Chen HH, Cox C, Katschke KJ, Arceo R, Espiritu C, Caplazi P, Nghiem SS, Chen YJ, Modrusan Z, Dressen A, Goldstein LD, Clarke C, Bhangale T, Yaspan B, Jeanne M, Townsend MJ, van Lookeren Campagne M, Hackney JA. Integration of eQTL and a Single-Cell Atlas in the Human Eye Identifies Causal Genes for Age-Related Macular Degeneration. Cell Rep 2020; 30:1246-1259.e6. [PMID: 31995762 DOI: 10.1016/j.celrep.2019.12.082] [Citation(s) in RCA: 120] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/04/2019] [Accepted: 12/19/2019] [Indexed: 12/11/2022] Open
Abstract
Age-related macular degeneration (AMD) is a leading cause of vision loss. To better understand disease pathogenesis and identify causal genes in GWAS loci for AMD risk, we present a comprehensive database of human retina and retinal pigment epithelium (RPE). Our database comprises macular and non-macular RNA sequencing (RNA-seq) profiles from 129 donors, a genome-wide expression quantitative trait loci (eQTL) dataset that includes macula-specific retina and RPE/choroid, and single-nucleus RNA-seq (NucSeq) from human retina and RPE with subtype resolution from more than 100,000 cells. Using NucSeq, we find enriched expression of AMD candidate genes in RPE cells. We identify 15 putative causal genes for AMD on the basis of co-localization of genetic association signals for AMD risk and eye eQTL, including the genes TSPAN10 and TRPM1. These results demonstrate the value of our human eye database for elucidating genetic pathways and potential therapeutic targets for ocular diseases.
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Affiliation(s)
- Luz D Orozco
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA 94080, USA
| | - Hsu-Hsin Chen
- Department of Biomarker Discovery OMNI, Genentech, South San Francisco, CA 94080, USA
| | - Christian Cox
- Department of Immunology Discovery, Genentech, South San Francisco, CA 94080, USA
| | - Kenneth J Katschke
- Department of Immunology Discovery, Genentech, South San Francisco, CA 94080, USA
| | - Rommel Arceo
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Carmina Espiritu
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Patrick Caplazi
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | | | - Ying-Jiun Chen
- Department of Molecular Biology, Genentech, South San Francisco, CA 94080, USA
| | - Zora Modrusan
- Department of Molecular Biology, Genentech, South San Francisco, CA 94080, USA
| | - Amy Dressen
- Department of Human Genetics, Genentech, South San Francisco, CA 94080, USA
| | - Leonard D Goldstein
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA 94080, USA; Department of Molecular Biology, Genentech, South San Francisco, CA 94080, USA
| | - Christine Clarke
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA 94080, USA
| | - Tushar Bhangale
- Department of Human Genetics, Genentech, South San Francisco, CA 94080, USA
| | - Brian Yaspan
- Department of Human Genetics, Genentech, South San Francisco, CA 94080, USA
| | - Marion Jeanne
- Department of Immunology Discovery, Genentech, South San Francisco, CA 94080, USA
| | - Michael J Townsend
- Department of Biomarker Discovery OMNI, Genentech, South San Francisco, CA 94080, USA.
| | | | - Jason A Hackney
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA 94080, USA.
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142
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Ninomiya W, Mizobuchi K, Hayashi T, Okude S, Katagiri S, Kubo A, Masuhara N, Nakano T. Electroretinographic abnormalities associated with pregabalin: a case report. Doc Ophthalmol 2020; 140:279-287. [DOI: 10.1007/s10633-019-09743-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Accepted: 12/18/2019] [Indexed: 12/29/2022]
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143
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Suppiej A, Marino S, Reffo ME, Maritan V, Vitaliti G, Mailo J, Falsaperla R. Early onset retinal dystrophies: clinical clues to diagnosis for pediatricians. Ital J Pediatr 2019; 45:168. [PMID: 31864384 PMCID: PMC6925422 DOI: 10.1186/s13052-019-0760-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 12/11/2019] [Indexed: 11/10/2022] Open
Abstract
Introduction Inherited retinal dystrophies are major cause of severe progressive vision loss in children. Early recognition and diagnosis are essential for timely visual rehabilitation during the appropriate stages of the visual development, as well as for genetic diagnosis and possible gene therapy. The aim of this study is to characterize a pattern of the initial visual symptoms, which could help the pediatricians and the primary care providers to suspect an inherited retinal disorder in its early stage. Methods We analyzed the initial clinical symptoms, based on parental report during the first visit to specialist, in 50 children diagnosed with retinal dystrophy confirmed by full-field electroretinography. The analysis included the age of symptoms onset and the type of visual symptoms, both in the total population and in the following diagnostic subgroups: rod-cone dystrophy (n.17), cone-rod dystrophy (n.12), achromatopsia (n.13), congenital stationary night blindness (n.6) and Leber’s congenital amaurosis (n.2). Results The majority of children (80%) had the onset of clinical symptoms before one year of age. The most frequent visual complaints reported by parents were nystagmus (76%), visual loss (28%) and photophobia (8%). Nystagmus was the first symptom reported by parents if the disease onset was before the age of six months, while the onset after the six months of age was more likely associated with the complain of vision loss. Conclusions Low vision and nystagmus observed by parents, particularly in the first year of life, may represent a red flag, prompting an appropriate ophthalmological workup for inherited retinal dystrophy.
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Affiliation(s)
- Agnese Suppiej
- Department of Medical Sciences - Pediatric Section, University of Ferrara, Ferrara, Italy. .,Robert Hollman Foundation, Padua, Italy.
| | - Silvia Marino
- Paediatric Operative Unit and Acute and Emergency, Policlinico Vittorio Emanuele University Hospital of Catania, Catania, Italy
| | | | | | - Giovanna Vitaliti
- Paediatric Operative Unit and Acute and Emergency, Policlinico Vittorio Emanuele University Hospital of Catania, Catania, Italy
| | - Janette Mailo
- Division of Pediatric Neurology, Stoller Children's Hospital, Edmonton, Alberta, Canada
| | - Raffaele Falsaperla
- Paediatric Operative Unit and Acute and Emergency, Policlinico Vittorio Emanuele University Hospital of Catania, Catania, Italy
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144
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Liang Q, Dharmat R, Owen L, Shakoor A, Li Y, Kim S, Vitale A, Kim I, Morgan D, Liang S, Wu N, Chen K, DeAngelis MM, Chen R. Single-nuclei RNA-seq on human retinal tissue provides improved transcriptome profiling. Nat Commun 2019; 10:5743. [PMID: 31848347 PMCID: PMC6917696 DOI: 10.1038/s41467-019-12917-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 10/02/2019] [Indexed: 12/23/2022] Open
Abstract
Single-cell RNA-seq is a powerful tool in decoding the heterogeneity in complex tissues by generating transcriptomic profiles of the individual cell. Here, we report a single-nuclei RNA-seq (snRNA-seq) transcriptomic study on human retinal tissue, which is composed of multiple cell types with distinct functions. Six samples from three healthy donors are profiled and high-quality RNA-seq data is obtained for 5873 single nuclei. All major retinal cell types are observed and marker genes for each cell type are identified. The gene expression of the macular and peripheral retina is compared to each other at cell-type level. Furthermore, our dataset shows an improved power for prioritizing genes associated with human retinal diseases compared to both mouse single-cell RNA-seq and human bulk RNA-seq results. In conclusion, we demonstrate that obtaining single cell transcriptomes from human frozen tissues can provide insight missed by either human bulk RNA-seq or animal models.
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Affiliation(s)
- Qingnan Liang
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, 77030, TX, USA
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Rachayata Dharmat
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, 77030, TX, USA
- St. Jude Children's Research Hospital, 262 Danny Thomas Pl, Memphis, TN, 38105, USA
| | - Leah Owen
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
| | - Akbar Shakoor
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
| | - Yumei Li
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Sangbae Kim
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Albert Vitale
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
| | - Ivana Kim
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
| | - Denise Morgan
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
- Department of Pharmacotherapy, the College of Pharmacy, University of Utah, Salt Lake City, UT, 84132, USA
| | - Shaoheng Liang
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Nathaniel Wu
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Ken Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Margaret M DeAngelis
- Department of Ophthalmology and Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA.
- Department of Pharmacotherapy, the College of Pharmacy, University of Utah, Salt Lake City, UT, 84132, USA.
- Department of Population Health Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA.
| | - Rui Chen
- HGSC, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, 77030, TX, USA.
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
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145
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Ivanova ME, Zolnikova IV, Gorgisheli KV, Atarshchikov DS, Ghosh P, Barh D. Novel frameshift mutation in NYX gene in a Russian family with complete congenital stationary night blindness. Ophthalmic Genet 2019; 40:558-563. [PMID: 31826698 DOI: 10.1080/13816810.2019.1698617] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: The complete form of X-linked congenital stationary night blindness (CSNB1A) is a very rare genetic disease caused by mutation in the NYX gene. CSNB1A-associated several mutations in the NYX gene have been reported earlier.Methods: In this case report, we have clinically diagnosed and genetically confirmed a novel mutation associated with CSNB1A in four members of a Russian family. Two male siblings from a family of four siblings (two girls, two boys) with non-progressive stable night blindness since early childhood and high myopia underwent - visual acuity test, perimetry, biomicroscopy, OCT, ophthalmoscopy, electroretinography, color vision Hue test, NGS based whole exome analysis and Sanger sequencing for clinical characterization and genetic confirmation of CSNB.Results: The members are clinically diagnosed and genetically confirmed with CSNB1A. All the patients had a novel frameshift mutation in the NYX gene (c.283delC, p.His95fs, NM_022567.2) that is found to segregate in X-linked mannerConclusions: This is probably the first case report with a novel mutation from Russia associated with CSNB1A.
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Affiliation(s)
| | | | | | | | - Preetam Ghosh
- Department of Computer Science, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Debmalya Barh
- Oftalmic LLC, Moscow, Russia.,Center for Genomics and Applied Gene Technology, Institute of Integrative Omics and Applied Biotechnology (IIOAB), Purba Medinipur, India
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146
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Malerba N, De Nittis P, Merla G. The Emerging Role of Gβ Subunits in Human Genetic Diseases. Cells 2019; 8:E1567. [PMID: 31817184 PMCID: PMC6952978 DOI: 10.3390/cells8121567] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 11/23/2019] [Accepted: 11/29/2019] [Indexed: 12/20/2022] Open
Abstract
Environmental stimuli are perceived and transduced inside the cell through the activation of signaling pathways. One common type of cell signaling transduction network is initiated by G-proteins. G-proteins are activated by G-protein-coupled receptors (GPCRs) and transmit signals from hormones, neurotransmitters, and other signaling factors, thus controlling a number of biological processes that include synaptic transmission, visual photoreception, hormone and growth factors release, regulation of cell contraction and migration, as well as cell growth and differentiation. G-proteins mainly act as heterotrimeric complexes, composed of alpha, beta, and gamma subunits. In the last few years, whole exome sequencing and biochemical studies have shown causality of disease-causing variants in genes encoding G-proteins and human genetic diseases. This review focuses on the G-protein β subunits and their emerging role in the etiology of genetically inherited rare diseases in humans.
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Affiliation(s)
- Natascia Malerba
- Division of Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, Viale Cappuccini, 71013 San Giovanni Rotondo (FG), Italy;
| | - Pasquelena De Nittis
- Center for Integrative Genomics, University of Lausanne, CH-1015 Lausanne, Switzerland;
| | - Giuseppe Merla
- Division of Medical Genetics Unit, IRCCS Casa Sollievo della Sofferenza, Viale Cappuccini, 71013 San Giovanni Rotondo (FG), Italy;
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147
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Kubota D, Oishi N, Gocho K, Kikuchi S, Yamaki K, Igarashi T, Takahashi H, Ishida N, Iwata T, Mizota A, Kameya S. Novel homozygous in-frame deletion of GNAT1 gene causes golden appearance of fundus and reduced scotopic ERGs similar to that in Oguchi disease in Japanese family. Ophthalmic Genet 2019; 40:480-487. [PMID: 31696758 DOI: 10.1080/13816810.2019.1686159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: The GNAT1 gene encodes the alpha-subunit of transducin in rod photoreceptors and is an important part of the phototransduction cascade. Defects in GNAT1 are very rare but have been identified in autosomal dominant and recessive congenital stationary night blindness (CSNB) and autosomal recessive rod-cone dystrophy. The purpose of this study was to determine the phenotype-genotype relationship in a non-consanguineous Japanese family with a GNAT1 mutation.Methods: Detailed ophthalmic examinations were performed on the patients and their family members. Whole exome sequencing (WES) was applied to the DNA obtained from the family members. Sanger sequencing and co-segregation analyses were performed to identify the most likely pathogenic variant.Results: Two female (13- and 11-years) and one male (15-years) patients from a family had night blindness from their childhood. The fundus had a mild golden appearance regardless of the state of light- or dark-adaptation. Electroretinographic (ERG) analyses showed that the scotopic a-wave was extinguished, and the mixed rod-cone responses were severely reduced with an electronegative form in patients. The shapes of the dark-adapted ERGs were similar to those recorded from patients with Oguchi disease. We identified a homozygous in-frame deletion c.818_820delAGA, p.Lys273del in the GNAT1 gene. Variants were verified by Sanger sequencing and co-segregated with the disease in five members of the family.Conclusions: Our findings indicate that a recessive GNAT1 mutation found in this family could be the cause of the golden appearance of the fundus and negative ERGs with reduced a-waves, and nearly absent b-waves in the mixed rod-cone ERGs.
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Affiliation(s)
- Daiki Kubota
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Noriko Oishi
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Kiyoko Gocho
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Sachiko Kikuchi
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Kunihiko Yamaki
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
| | - Tsutomu Igarashi
- Department of Ophthalmology, Nippon Medical School, Tokyo, Japan
| | | | | | - Takeshi Iwata
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, Tokyo, Japan
| | - Atsushi Mizota
- Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan
| | - Shuhei Kameya
- Department of Ophthalmology, Nippon Medical School Chiba Hokusoh Hospital, Inzai, Chiba, Japan
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148
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Liu HY, Huang J, Xiao H, Zhang MJ, Shi FF, Jiang YH, Du H, He Q, Wang ZY. Pseudodominant inheritance of autosomal recessive congenital stationary night blindness in one family with three co-segregating deleterious GRM6 variants identified by next-generation sequencing. Mol Genet Genomic Med 2019; 7:e952. [PMID: 31677249 PMCID: PMC6900388 DOI: 10.1002/mgg3.952] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The congenital stationary night blindness (CSNB) affects the patients' dim light vision or dark adaption by impairing the normal function of retina. It is a clinically and genetically heterogeneous disorder and can be inherited in an X-linked, autosomal dominant or autosomal recessive pattern. Several genetic alterations to the genes involved in visual signal transduction of photoreceptors and/or bipolar cells underlie its pathogenesis. METHODS In this study, we used Sanger sequencing and next-generation sequencing (NGS)-based gene panel screening to investigate a family of three patients with CSNB inherited in an apparent autosomal dominant pattern. We expected to find out the disease-causing gene defects carried by this family. RESULTS We found that the patients in this family did not carry the RHO, GNAT1, or PDE6B mutation, but carried compound heterozygotes mutations of GRM6. Three deleterious GRM6 variants, p.Arg621Ter, p.Gly51Val, and p.Gly464Arg, were found to be co-segregating with the disease, causing a pseudodominant inheritance of GRM6-related autosomal recessive complete CSNB. CONCLUSION This study presents a rare case of autosomal recessive CSNB (arCSNB) pseudodominant inheritance, which potentially leads us to expand our gene candidate list in future genetic testing for apparent dominant pedigrees. The discovery of the two novel likely pathogenic variants p.Gly51Val and p.Gly464Arg could broaden our knowledge about the genetics of CSNB and provide insights into the structure and function of the GRM6 protein.
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Affiliation(s)
- Hong-Yan Liu
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Jia Huang
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Hai Xiao
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Ming-Jie Zhang
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Fei-Fei Shi
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Ying-Hai Jiang
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
| | - Han Du
- Institute of Medical Genetics, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, China
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Kimchi A, Meiner V, Silverstein S, Macarov M, Mor-Shaked H, Blumenfeld A, Audo I, Zeitz C, Mechoulam H, Banin E, Sharon D, Yahalom C. An Ashkenazi Jewish founder mutation in CACNA1F causes retinal phenotype in both hemizygous males and heterozygous female carriers. Ophthalmic Genet 2019; 40:443-448. [PMID: 31651202 DOI: 10.1080/13816810.2019.1681008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Background: Mutations in CACNA1F have been mainly associated with X-linked incomplete congenital stationary night blindness (icCSNB). Variable phenotypic expression in females was reported in some families. We report here three non-related Ashkenazi Jewish families originating in Eastern Europe, that included males and a many affected females, initially diagnosed with variable retinal phenotypes.Materials and Methods: Whole exome sequencing (WES), Sanger sequencing and microsatellite haplotyping were used for genetic analysis. Complete ophthalmologic examination was performed including visual acuity, refraction, colour vision, slit-lamp, fundoscopy and electroretinography (ERG).Results: We identified four affected males, showing moderate visual impairment, and seven female carriers, six of them presenting mild to moderate visual impairment. Infantile nystagmus was found in all affected males and in 5/7 females. Nyctalopia and myopia were common in both males and females. Initial clinical differential diagnosis included cone-dystrophy, cone-rod dystrophy, cone-dystrophy with supernormal rod response or CSNB based on ERG results. WES and Sanger sequencing revealed a previously described missense mutation c.2225T>G; p.(F742C) in CACNA1F (NM_001256789.2) in all three families, encompassed by a shared haplotypeConclusions: Our data suggests that p.(F742C) in CACNA1F is an X-linked founder mutation in Ashkenazi Jews originating in Eastern Europe. This mutation causes a mild-to-moderate icCSNB phenotype, expressed in most female carriers. A targeted test for this variant in suspected patients may initiate diagnostic analysis. Our results highlight the relevance of WES in the clinic, allowing fast and accurate diagnosis for unclear and variable clinical phenotype and in pedigrees with multiple possible inheritance patterns.
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Affiliation(s)
- Adva Kimchi
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.,Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Vardiella Meiner
- Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Shira Silverstein
- Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Michal Macarov
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.,Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Hagar Mor-Shaked
- Department of Genetics and Metabolic Diseases, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Anat Blumenfeld
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Isabelle Audo
- Institut de la vision, Sorbonne Université, INSERM, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS, Paris, France.,Institute of Ophthalmology, University College of London, London, UK
| | - Christina Zeitz
- Institut de la vision, Sorbonne Université, INSERM, Paris, France
| | - Hadas Mechoulam
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Sharon
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Claudia Yahalom
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Allon G, Friedrich Y, Mezer E, Itzhaki A, Leibu R, Perlman I. Verifying complaints of difficulties in night vision using electroretinography and dark adaptation tests. Doc Ophthalmol 2019; 140:169-180. [PMID: 31621038 DOI: 10.1007/s10633-019-09729-z] [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: 04/21/2019] [Accepted: 10/04/2019] [Indexed: 10/25/2022]
Abstract
PURPOSE To determine the electroretinographical and psychophysical parameters that can help to verify patients' complaints of reduced night vision. METHODS We tested 275 consecutive patients with normal appearing fundi, complaining of visual difficulties at night, using flash electroretinography (ERG) and dark adaptation (DA) test. Two ERG parameters were used to assess a scotopic retinal function: the amplitude of the response to dim blue flash (the rod response) and the b-wave ratio (measured/expected). Dark adaptation was measured with green- and red-light stimuli after exposure to a bright, bleaching light. The psychophysical parameter of night vision was defined as the threshold for detection of the blue-green stimulus that was measured after 40-45 min in complete darkness. RESULTS Fifty-five patients were excluded from the analysis because of a discrepancy between the two ERG parameters in assessment of scotopic retinal function. The remaining 220 patients were divided into 4 groups: (1) normal ERG and normal DA, (2) subnormal ERG and subnormal DA, (3) normal ERG and subnormal DA and (4) subnormal ERG and normal DA. The ERG and DA tests supported the complaint of visual difficulties at night in 67 patients (group 2), while 34 patients were characterized as having normal scotopic visual function (group 1). The other 119 patients (groups 3 and 4) presented a diagnostic dilemma because one test (ERG or dark adaptation) showed normal scotopic function, while the other indicated subnormal scotopic function. CONCLUSION Our findings indicate that ERG is an essential, but not sufficient test for verifying patient's complaint on visual difficulties in the dark. We suggest using both electroretinography and psychophysical dark adaptation to test patients complaining of reduced night vision.
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Affiliation(s)
- Gilad Allon
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,Department of Ophthalmology, Rambam Health Care Campus, Haifa, Israel
| | | | - Eedy Mezer
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.,Department of Ophthalmology, Rambam Health Care Campus, Haifa, Israel
| | - Aviran Itzhaki
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Rina Leibu
- Department of Ophthalmology, Rambam Health Care Campus, Haifa, Israel
| | - Ido Perlman
- Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
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