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Nassisi M, Coarelli G, Blanchard B, Dubec-Fleury C, Drine K, Kitic N, Sancho S, Hilab R, Tezenas du Montcel S, Junge C, Lane R, Arnold HM, Durr A, Audo I. ATXN7-Related Cone-Rod Dystrophy: The Integrated Functional Evaluation of the Cerebellum (CERMOI) Study. JAMA Ophthalmol 2024; 142:301-308. [PMID: 38421662 PMCID: PMC10905377 DOI: 10.1001/jamaophthalmol.2024.0001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/15/2023] [Indexed: 03/02/2024]
Abstract
Importance Reliable biomarkers with diagnostic and prognostic values are needed for upcoming gene therapy trials for spinocerebellar ataxias. Objective To identify ophthalmological biomarkers in a sample of spinocerebellar ataxia type 7 (SCA7) carriers. Design, Setting, and Participants This article presents baseline data from a cross-sectional natural history study conducted in Paris, France, reference centers for rare diseases from May 2020 to April 2021. Data were analyzed from September to December 2022. Fifteen adult ATXN7 pathogenic expansion carriers (9 with preataxia and 6 with ataxia) were included, all with a Scale for the Assessment and Rating of Ataxia (SARA) score of 15 of 40 or lower. Patients were recruited at the Paris Brain Institute, and all contacted patients accepted to participate in the study. Main Outcomes and Measures Three visits (baseline, 6 months, and 12 months) were planned, including neurological examination (SARA and Composite Cerebellar Functional Severity Score), ophthalmological examination (best-corrected visual acuity, microperimetry, full-field electroretinogram, optical coherence tomography, and fundus autofluorescence imaging), and neurofilament light chain (NfL) measurements. Here we report the baseline ophthalmic data from the cohort and determine whether there is a correlation between disease scores and ophthalmic results. Results Among the 15 included SCA7 carriers (median [range] age, 38 [18-60] years; 8 women and 7 men), 12 displayed cone or cone-rod dystrophy, with the number of CAG repeats correlating with disease severity (ρ, 0.73, 95% CI, 0.34 to 0.90; P < .001). Two patients with cone-rod dystrophy exhibited higher repeat numbers and greater ataxia scores (median [range] SARA score, 9 [7-15]) compared to those with only cone dystrophy (median [range] SARA score, 2 [0-5]). A correlation emerged for outer nuclear layer thickness with SARA score (ρ, -0.88; 95% CI, -0.96 to -0.59; P < .001) and NfL levels (ρ, -0.87; 95% CI, -0.86 to 0.96; P < .001). Moreover, ataxia severity was correlated with visual acuity (ρ: 0.89; 95% CI, 0.68 to 0.96; P < .001) and retinal sensitivity (ρ, -0.88; 95% CI, -0.96 to 0.59; P < .001). Conclusions and Relevance In this cross-sectional study, retinal abnormalities were found at preataxic stages of the disease. Most of the carriers presented with cone dystrophy and preserved rod function. The outer nuclear layer thickness correlated with SARA score and plasma NfL levels suggesting nuclear layer thickness to be a biomarker of disease severity. These findings contribute to understanding the dynamics of SCA7-related retinal dystrophy and may help lay the groundwork for future therapeutic intervention monitoring and clinical trials. Trial Registration ClinicalTrials.gov Identifier: NCT04288128.
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Affiliation(s)
- Marco Nassisi
- Sorbonne Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Institut de la Vision, Paris, France
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
| | - Giulia Coarelli
- Sorbonne Université, Institut du Cerveau, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Paris, France
- Assistance Publique – Hôpitaux de Paris, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Benoit Blanchard
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
| | - Charlotte Dubec-Fleury
- Sorbonne Université, Institut du Cerveau, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Paris, France
- Assistance Publique – Hôpitaux de Paris, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Karima Drine
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
| | - Nicolas Kitic
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
| | - Serge Sancho
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
| | - Rania Hilab
- Sorbonne Université, Institut du Cerveau, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Paris, France
- Assistance Publique – Hôpitaux de Paris, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Sophie Tezenas du Montcel
- Sorbonne Université, Institut du Cerveau, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Paris, France
- Assistance Publique – Hôpitaux de Paris, Hôpital de la Pitié Salpêtrière, Paris, France
| | | | - Roger Lane
- Ionis Pharmaceuticals, Carlsbad, California
| | | | - Alexandra Durr
- Sorbonne Université, Institut du Cerveau, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Paris, France
- Assistance Publique – Hôpitaux de Paris, Hôpital de la Pitié Salpêtrière, Paris, France
| | - Isabelle Audo
- Sorbonne Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Institut de la Vision, Paris, France
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, National Rare Disease Center REFERET and Institut national de la santé et de la recherche médicale Directorate General of Health Care Provision, Centres d’Investigations Cliniques 1423, Paris, France
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Hizem S, Maamouri R, Zaouak A, Rejeb I, Karoui S, Sebai M, Jilani H, Elaribi Y, Fenniche S, Cheour M, Bilan F, Ben Jemaa L. Absent meibomian glands and cone dystrophy in ADULT syndrome: identification by whole exome sequencing of pathogenic variants in two causal genes TP63 and CNGB3. Ophthalmic Genet 2024; 45:84-94. [PMID: 37158316 DOI: 10.1080/13816810.2023.2206891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 04/20/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Ectrodactyly is a rare congenital limb malformation characterized by a deep median cleft of the hand and/or foot due to the absence of central rays. It could be isolated or depicts a part of diverse syndromic forms. Heterozygous pathogenic variants in the TP63 gene are responsible for at least four rare syndromic human disorders associated with ectrodactyly. Among them, ADULT (Acro-Dermato-Ungual-Lacrimal-Tooth) syndrome is characterized by ectodermal dysplasia, excessive freckling, nail dysplasia, and lacrimal duct obstruction, in addition to ectrodactyly and/or syndactyly. Ophthalmic findings are very common in TP63-related disorders, consisting mainly of lacrimal duct hypoplasia. Absent meibomian glands have also been well documented in EEC3 (Ectrodactyly Ectodermal dysplasia Cleft lip/palate) syndrome but not in ADULT syndrome. METHODS We report a case of syndromic ectrodactyly consistent with ADULT syndrome, with an additional ophthalmic manifestation of agenesis of meibomian glands. The proband, as well as her elder sister, presented with congenital cone dystrophy.The molecular investigation was performed in the proband using Whole Exome Sequencing. Family segregation of the identified variants was confirmed by Sanger sequencing. RESULTS Two clinically relevant variants were found in the proband: the novel de novo heterozygous missense c.931A > G (p.Ser311Gly) in the TP63 gene classified as pathogenic, and the homozygous nonsense pathogenic c.1810C > T (p.Arg604Ter) in the CNGB3 gene. The same homozygous CNGB3 variation was also found in the sister, explaining the cone dystrophy in both cases. CONCLUSIONS Whole Exome Sequencing allowed dual molecular diagnoses: de novo TP63-related syndromic ectrodactyly and familial CNGB3-related congenital cone dystrophy.
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Affiliation(s)
- Syrine Hizem
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Human genetics laboratory, LR99ES10- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Rym Maamouri
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Department of Ophthalmology, Habib Thameur hospital, Tunis, Tunisia
| | - Anissa Zaouak
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Department of Dermatology, Genodermatosis and Cancers Laboratory LR12SP03, Habib Thameur Hospital, Tunis, Tunisia
| | - Imen Rejeb
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Maternal and Child health laboratory, LR22SP01- Mongi Slim Hospital, Tunis, Tunisia
| | - Sana Karoui
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Maternal and Child health laboratory, LR22SP01- Mongi Slim Hospital, Tunis, Tunisia
| | - Molka Sebai
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Human genetics laboratory, LR99ES10- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Houweyda Jilani
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Yasmina Elaribi
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Sami Fenniche
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Department of Dermatology, Genodermatosis and Cancers Laboratory LR12SP03, Habib Thameur Hospital, Tunis, Tunisia
| | - Monia Cheour
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Department of Ophthalmology, Habib Thameur hospital, Tunis, Tunisia
| | - Frédéric Bilan
- Laboratoire de Génétique, Service de Génétique, CHU Poitiers, Poitiers, France
| | - Lamia Ben Jemaa
- Department of congenital and hereditary diseases, Mongi Slim hospital, La Marsa, Tunisia
- Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia
- Maternal and Child health laboratory, LR22SP01- Mongi Slim Hospital, Tunis, Tunisia
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3
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Kolawole OU, Gregory-Evans CY, Bikoo R, Huang AZ, Gregory-Evans K. Novel pathogenic variants in Tubulin Tyrosine Like 5 ( TTLL5) associated with cone-dominant retinal dystrophies and an abnormal optical coherence tomography phenotype. Mol Vis 2023; 29:329-337. [PMID: 38264610 PMCID: PMC10805330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 12/10/2023] [Indexed: 01/25/2024] Open
Abstract
Purpose Autosomal recessive cone and cone-rod dystrophies (CD/CRD) are inherited forms of vison loss. Here, we report on and correlate the clinical phenotypes with the underlying genetic mutations. Methods Clinical information was collected from subjects, including a family history with a chart review. They underwent a full ophthalmic examination, including best-corrected visual acuity, direct and indirect ophthalmoscopy, color vision testing, color fundus photography, contrast sensitivity, autofluorescence, and spectral domain-optical coherence tomography (SD-OCT), and full-field electroretinography. Next-generation panel-based genetic testing was used to identify DNA variants in subject buccal swab samples. Results Genetic testing in two patients revealed three novel variants in the TTLL5 gene associated with CD/CRD: two missense variants (c.1433G>A;p.(Arg478Gln), c.241C>G;p.(Leu81Val), and one loss-of-function variant (c.2384_2387del;p.(Ala795Valfs*9). Based on in-silico analysis, structural modeling, and comparison to previously reported mutations, these novel variants are very likely to be disease-causing mutations. Combining retinal imaging with SD-OCT analysis, we observed an unusual sheen in the CD/CRD phenotypes. Conclusion Based on the protein domain location of novel TTLL5 variants and the localization of TTLL5 to the connecting cilium, we conclude that the CD/CRD disease phenotype is characterized as a ciliopathy caused by protein tracking dysfunction. This initially affects cone photoreceptors, where photoreceptor cilia express a high level of TTLL5, but extends to rod photoreceptors over time. Fundus photography correlated with SD-OCT imaging suggests that the macular sheen characteristically seen with TTLL5 mutations derives from the photoreceptor's outer segments at the posterior pole.
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Affiliation(s)
- Olubayo U Kolawole
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | | | - Riyaz Bikoo
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | - Albert Z Huang
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
| | - Kevin Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Canada
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Pasquier L, Coursimault J, Side W, Goldenberg A, Muraine M. [KCNV2-associated cone dystrophy case report: Clinical and electrophysiological features]. J Fr Ophtalmol 2023; 46:e374-e377. [PMID: 37661494 DOI: 10.1016/j.jfo.2023.05.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 09/05/2023]
Affiliation(s)
- L Pasquier
- Service d'ophtalmologie, CHU de Charles-Nicolle, 1, rue de Germont, 76031 Rouen cedex, France.
| | - J Coursimault
- Service de génétique clinique, CHU de Charles-Nicolle, 1, rue de Germont, 76031 Rouen cedex, France
| | - W Side
- Cabinet d'ophtalmologie, 304, rue Jean-Badin, 76360 Barentin, France
| | - A Goldenberg
- Service de génétique clinique, CHU de Charles-Nicolle, 1, rue de Germont, 76031 Rouen cedex, France
| | - M Muraine
- Service d'ophtalmologie, CHU de Charles-Nicolle, 1, rue de Germont, 76031 Rouen cedex, France
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Bonetti G, Cozza W, Bernini A, Kaftalli J, Mareso C, Cristofoli F, Medori MC, Colombo L, Martella S, Staurenghi G, Salvetti AP, Falsini B, Placidi G, Attanasio M, Pertile G, Bengala M, Bosello F, Petracca A, D’Esposito F, Toschi B, Lanzetta P, Ricci F, Viola F, Marceddu G, Bertelli M. Towards a Long-Read Sequencing Approach for the Molecular Diagnosis of RPGR ORF15 Genetic Variants. Int J Mol Sci 2023; 24:16881. [PMID: 38069202 PMCID: PMC10706286 DOI: 10.3390/ijms242316881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
Sequencing of the low-complexity ORF15 exon of RPGR, a gene correlated with retinitis pigmentosa and cone dystrophy, is difficult to achieve with NGS and Sanger sequencing. False results could lead to the inaccurate annotation of genetic variants in dbSNP and ClinVar databases, tools on which HGMD and Ensembl rely, finally resulting in incorrect genetic variants interpretation. This paper aims to propose PacBio sequencing as a feasible method to correctly detect genetic variants in low-complexity regions, such as the ORF15 exon of RPGR, and interpret their pathogenicity by structural studies. Biological samples from 75 patients affected by retinitis pigmentosa or cone dystrophy were analyzed with NGS and repeated with PacBio. The results showed that NGS has a low coverage of the ORF15 region, while PacBio was able to sequence the region of interest and detect eight genetic variants, of which four are likely pathogenic. Furthermore, molecular modeling and dynamics of the RPGR Glu-Gly repeats binding to TTLL5 allowed for the structural evaluation of the variants, providing a way to predict their pathogenicity. Therefore, we propose PacBio sequencing as a standard procedure in diagnostic research for sequencing low-complexity regions such as RPGRORF15, aiding in the correct annotation of genetic variants in online databases.
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Affiliation(s)
- Gabriele Bonetti
- MAGI’s LAB, 38068 Rovereto, Italy; (M.C.M.); (M.B.)
- Department of Pharmaceutical Sciences, University of Perugia, 06123 Perugia, Italy
| | - William Cozza
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Andrea Bernini
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, 53100 Siena, Italy;
| | - Jurgen Kaftalli
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Chiara Mareso
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | | | | | - Leonardo Colombo
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, 20142 Milan, Italy; (L.C.); (S.M.)
| | - Salvatore Martella
- Department of Ophthalmology, ASST Santi Paolo e Carlo Hospital, University of Milan, 20142 Milan, Italy; (L.C.); (S.M.)
| | - Giovanni Staurenghi
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, 20157 Milan, Italy; (G.S.); (A.P.S.)
| | - Anna Paola Salvetti
- Eye Clinic, Department of Biomedical and Clinical Science, Luigi Sacco Hospital, University of Milan, 20157 Milan, Italy; (G.S.); (A.P.S.)
| | - Benedetto Falsini
- UOC Oculistica, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, Largo Gemelli 8, 00168 Rome, Italy (G.P.)
- Istituto di Oftalmologia, Università Cattolica del Sacro Cuore, Largo Francesco Vito 1, 00168 Rome, Italy
| | - Giorgio Placidi
- UOC Oculistica, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, Largo Gemelli 8, 00168 Rome, Italy (G.P.)
| | - Marcella Attanasio
- Ospedale Sacrocuore Don Calabria, Viale Luigi Rizzardi, 4, 37024 Negrar di Valpolicella, Italy; (M.A.); (G.P.)
| | - Grazia Pertile
- Ospedale Sacrocuore Don Calabria, Viale Luigi Rizzardi, 4, 37024 Negrar di Valpolicella, Italy; (M.A.); (G.P.)
| | - Mario Bengala
- Medical Genetics Unit, Department of Oncohematology, Policlinico Tor Vergata, 00133 Rome, Italy;
| | - Francesca Bosello
- Department of Surgical Sciences, Dentistry, Paediatrics and Gynaecology, Section of Ophthalmology, University of Verona, 37134 Verona, Italy;
| | - Antonio Petracca
- Division of Medical Genetics, Fondazione IRCCS-Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy;
| | - Fabiana D’Esposito
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
- Imperial College Ophthalmic Research Group (ICORG) Unit, Imperial College, London NW1 5QH, UK
- Eye Clinic, Department of Neurosciences, Reproductive Sciences and Dentistry, University of Naples Federico II, 80138 Naples, Italy
| | - Benedetta Toschi
- Section of Medical Genetics, Department of Medical and Oncological Area, University Hospital of Pisa, 56126 Pisa, Italy;
| | - Paolo Lanzetta
- Department of Medicine-Ophthalmology, University of Udine, 33100 Udine, Italy;
- Istituto Europeo di Microchirurgia Oculare (IEMO), 33100 Udine, Italy
| | - Federico Ricci
- Department of Experimental Medicine, Tor Vergata University of Rome, Viale Oxford, 00133 Rome, Italy;
| | - Francesco Viola
- Department of Ophthalmology, Fondazione IRCCS Cà Granda, Clinica Regina Elena, 20122 Milan, Italy;
| | - Giuseppe Marceddu
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
| | - Matteo Bertelli
- MAGI’s LAB, 38068 Rovereto, Italy; (M.C.M.); (M.B.)
- MAGI Euregio, 39100 Bolzano, Italy; (W.C.); (J.K.); (C.M.); (F.D.); (G.M.)
- MAGISNAT, Atlanta Tech Park, 107 Technology Parkway, Peachtree Corners, GA 30092, USA
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Zhang LJ, Li Y, You Y, Lei B. [Supernormal rod response mediated by a novel KCNV2 variant in a cone dystrophy type 3B patient]. Zhonghua Yan Ke Za Zhi 2022; 58:376-379. [PMID: 35511665 DOI: 10.3760/cma.j.cn112142-20210916-00431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The proband was an 8-year-old boy, complaining of progressively decreased vision in both eyes for 3 years. The electroretinogram was characterized by supernormal rod response. While the responses of the rod and cone system were reduced, the amplitudes of dark-adapted electroretinogram responses at a high intensity were supernormal. A homozygous non-frameshift deletion variant c.1002-1004del (p. L335del) in KCNV2 was found by the Next Generation Sequencing using a custom designed panel. His father was a heterozygous carrier of this variant. In silico analysis indicated the variant was harmful. The proband was diagnosed as cone dystrophy type 3B which also known as cone dystrophy with supernormal rod response.
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Affiliation(s)
- L J Zhang
- Henan Eye Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Zhengzhou 450003, China
| | - Y Li
- Henan Eye Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Zhengzhou 450003, China
| | - Y You
- Henan Eye Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Zhengzhou 450003, China
| | - B Lei
- Henan Eye Hospital, Henan Provincial People's Hospital, Henan Eye Institute, Zhengzhou 450003, China
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7
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Affiliation(s)
- Akash Belenje
- Smt Kanuri Santhamma Centre for Vitreoretinal diseases, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Brijesh Takkar
- Smt Kanuri Santhamma Centre for Vitreoretinal diseases, LV Prasad Eye Institute, Hyderabad, Telangana, India
- Center of Excellence for Rare Eye Diseases, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Raja Narayanan
- Smt Kanuri Santhamma Centre for Vitreoretinal diseases, LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Subhadra Jalali
- Smt Kanuri Santhamma Centre for Vitreoretinal diseases, LV Prasad Eye Institute, Hyderabad, Telangana, India
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