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Liu Y, Tai J, Yu C, Xu D, Xiao D, Pang J. Unlocking therapeutic potential: dual gene therapy for ameliorating the disease phenotypes in a mouse model of RPE65 Leber congenital amaurosis. Front Med (Lausanne) 2024; 10:1291795. [PMID: 38264046 PMCID: PMC10803578 DOI: 10.3389/fmed.2023.1291795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Accepted: 12/27/2023] [Indexed: 01/25/2024] Open
Abstract
Leber congenital amaurosis (LCA) is the most common genetic cause of congenital visual impairment in infants and children. Patients with LCA who harbor RPE65 mutations exhibit a deficiency in photoreceptor rhodopsin, leading to severe night blindness and visual impairment following birth. Since either gene replacement therapy or anti-apoptosis therapy alone cannot maintain both functional and morphological normality for a long time in the animal model, we propose a robust treatment strategy, that is, gene replacement therapy combined with anti-apoptotic therapy to protect photoreceptors from further degeneration while compensating for lost RPE65 function. Here, rd12 mice were injected subretinally at postnatal day 14 with four vector administrations, respectively. At 6 months after treatment, it was discovered that injection of three vectors, AAV8 (Y733F)-CBA-hRPE65, AAV8(Y733F)-CBA-hRPE65-BCL-2-L10 and mixture of half-dose AAV8(Y733F)-CBA-hRPE65 and half-dose AAV8 (Y733F)-CBA-BCL-2-L10, could partially restore the visual function of rd12 mice. Meanwhile, these treated eyes also exhibited a thicker outer nuclear layer (ONL) structure. However, despite the fact that the eyes of rd12 mice injected with the AAV8 (Y733F)-CBA-BCL-2-L10 vector displayed a slightly thicker ONL structure compared to untreated eyes, the visual function of the treated eyes did not recover. Continuing the observation period to 12 months after treatment, we found that compared to rd12 mice at 6-month post-treatment, rd12 mice injected with AAV8 (Y733F)-CBA-hRPE65 or mixture of half-dose AAV8(Y733F)-CBA-hRPE65 and half-dose AAV8 (Y733F)-CBA-BCL-2-L10 exhibited varying degrees of decline in both visual function and ONL thickness. However, in the case of rd12 mice injected with the AAV8(Y733F)-CBA-hRPE65-BCL-2-L10 vector, the ONL thickness remains consistent at both 6 and 12 months after treatment. These mice continued to maintain a relatively strong visual function and showed restoration in the levels of RPE65 and Rhodopsin protein expression. Our findings illustrate that early postnatal treatment with AAV vectors containing both the hRPE65 gene and the Bcl-2L10 anti-apoptotic gene provide enhanced and sustained retinal protection.
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Affiliation(s)
- Yanbo Liu
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, School of Medicine, Xiamen University, Xiamen, China
| | - Jingjie Tai
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, School of Medicine, Xiamen University, Xiamen, China
| | - Chaofeng Yu
- Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, School of Medicine, Xiamen University, Xiamen, China
| | - Dan Xu
- Shenyang Weijing Biotechnology Co., Ltd., Shenyang, China
| | - Dan Xiao
- Xiamen University Affiliated Xiamen Eye Center, Xiamen, China
| | - Jijing Pang
- Shenyang Weijing Biotechnology Co., Ltd., Shenyang, China
- Xiamen University Affiliated Xiamen Eye Center, Xiamen, China
- Shenyang He Eye Specialist Hospital, Shenyang, China
- Institute of Innovation Research for Precision Medical Treatment, He University, Shenyang, China
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Wong WM, Tham YC, Simunovic MP, Chen FK, Luu CD, Chen H, Jin ZB, Shen RJ, Li S, Sui R, Zhao C, Yang L, Bhende M, Raman R, Sen P, Ghosh A, Poornachandra B, Sasongko MB, Arianti A, Chia V, Mangunsong CO, Manurung F, Fujinami K, Ikeda H, Woo SJ, Kim SJ, Mohd Khialdin S, Othman O, Bastion MLC, Kamalden AT, Lott PWP, Fong K, Shunmugam M, Lim A, Thapa R, Pradhan E, Rajkarnikar SP, Adhikari S, Ibañez BMBI, Koh A, Chan CMM, Fenner BJ, Tan TE, Laude A, Ngo WK, Holder GE, Su X, Chen TC, Wang NK, Kang EYC, Huang CH, Surawatsatien N, Pisuchpen P, Sujirakul T, Kumaramanickavel G, Singh M, Leroy B, Michaelides M, Cheng CY, Chen LJ, Chan HW. Rationale and protocol paper for the Asia Pacific Network for inherited eye diseases. Asia Pac J Ophthalmol (Phila) 2024; 13:100030. [PMID: 38233300 DOI: 10.1016/j.apjo.2023.100030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/16/2023] [Accepted: 11/21/2023] [Indexed: 01/19/2024] Open
Abstract
PURPOSE There are major gaps in our knowledge of hereditary ocular conditions in the Asia-Pacific population, which comprises approximately 60% of the world's population. Therefore, a concerted regional effort is urgently needed to close this critical knowledge gap and apply precision medicine technology to improve the quality of lives of these patients in the Asia-Pacific region. DESIGN Multi-national, multi-center collaborative network. METHODS The Research Standing Committee of the Asia-Pacific Academy of Ophthalmology and the Asia-Pacific Society of Eye Genetics fostered this research collaboration, which brings together renowned institutions and experts for inherited eye diseases in the Asia-Pacific region. The immediate priority of the network will be inherited retinal diseases (IRDs), where there is a lack of detailed characterization of these conditions and in the number of established registries. RESULTS The network comprises 55 members from 35 centers, spanning 12 countries and regions, including Australia, China, India, Indonesia, Japan, South Korea, Malaysia, Nepal, Philippines, Singapore, Taiwan, and Thailand. The steering committee comprises ophthalmologists with experience in consortia for eye diseases in the Asia-Pacific region, leading ophthalmologists and vision scientists in the field of IRDs internationally, and ophthalmic geneticists. CONCLUSIONS The Asia Pacific Inherited Eye Disease (APIED) network aims to (1) improve genotyping capabilities and expertise to increase early and accurate genetic diagnosis of IRDs, (2) harmonise deep phenotyping practices and utilization of ontological terms, and (3) establish high-quality, multi-user, federated disease registries that will facilitate patient care, genetic counseling, and research of IRDs regionally and internationally.
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Affiliation(s)
- Wendy M Wong
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, National University Hospital, National University Health System, Singapore
| | - Yih Chung Tham
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Matthew P Simunovic
- Save Sight Institute, The University of Sydney, Sydney, Australia; Retinal Unit, Sydney Eye Hospital, Sydney, Australia
| | - Fred Kuanfu Chen
- Centre for Ophthalmology and Visual Science (Lions Eye Institute), The University of Western Australia, Nedlands, Western Australia, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
| | - Chi D Luu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia; Ophthalmology, Department of Surgery, University of Melbourne, East Melbourne, Victoria, Australia
| | - Haoyu Chen
- Joint Shantou International Eye Center, Shantou University & The Chinese University of Hong Kong, Shantou, China
| | - Zi-Bing Jin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Ren-Juan Shen
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Shiying Li
- Department of Ophthalmology in Xiang'an Hospital of Xiamen University and Medical Center of Xiamen University, School of Medicine in Xiamen University, Eye Institute of Xiamen University, Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Fujian Engineering and Research Center of Eye Regenerative Medicine, Xiamen, Fujian, China
| | - Ruifang Sui
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, No. 1, Shuai Fu Yuan, Beijing, China
| | - Chen Zhao
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Liping Yang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China; Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Muna Bhende
- Shri Bhagwan Mahavir Vitreoretinal services, Medical Research Foundation, Sankara Nethralaya, Chennai, India
| | - Rajiv Raman
- Shri Bhagwan Mahavir Vitreoretinal services, Medical Research Foundation, Sankara Nethralaya, Chennai, India
| | - Parveen Sen
- Shri Bhagwan Mahavir Vitreoretinal services, Medical Research Foundation, Sankara Nethralaya, Chennai, India; Dr Agarwal Eye Hospital, Chandigarh, India
| | - Arkasubhra Ghosh
- GROW Lab, Narayana Nethralaya Foundation, Bangalore, Karnataka, India
| | - B Poornachandra
- Vitreo-Retina Services, Narayana Nethralaya, Bangalore, India
| | - Muhammad Bayu Sasongko
- Department of Ophthalmology, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada - Sardjito Eye Center, Dr. Sardjito General Hospital, Yogyakarta, Indonesia
| | - Alia Arianti
- JEC Eye Hospitals and Clinics, Jakarta, Indonesia
| | - Valen Chia
- JEC Eye Hospitals and Clinics, Jakarta, Indonesia
| | | | | | - Kaoru Fujinami
- Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, NHO Tokyo Medical Center, Tokyo, Japan
| | - Hanako Ikeda
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Japan
| | - Se Joon Woo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Sang Jin Kim
- Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Safinaz Mohd Khialdin
- Department of Ophthalmology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia; UKM Specialist Children's Hospital, Kuala Lumpur, Malaysia
| | - Othmaliza Othman
- Department of Ophthalmology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia
| | - Mae-Lynn Catherine Bastion
- Department of Ophthalmology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia; Hospital Canselor Tuanku Muhriz, Jalan Yaacob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia
| | - Ain Tengku Kamalden
- UM Eye Research Centre, Department of Ophthalmology, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Pooi Wah Penny Lott
- UM Eye Research Centre, Department of Ophthalmology, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | | | - Amelia Lim
- Ophthalmology, Penang Gleneagles, Malaysia
| | - Raba Thapa
- Tilganga Institute of Ophthalmology, Kathmandu, Nepal
| | - Eli Pradhan
- Tilganga Institute of Ophthalmology, Kathmandu, Nepal
| | | | | | - B Manuel Benjamin Iv Ibañez
- Makati Medical Center, Makati City, Philippines; DOH Eye Center, East Avenue Medical Center, Quezon City, Philippines
| | - Adrian Koh
- Eye & Retina Surgeons, Camden Medical Centre, Singapore, Singapore
| | - Choi Mun M Chan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (EYE ACP), Duke-NUS Medical School, Singapore
| | - Beau J Fenner
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (EYE ACP), Duke-NUS Medical School, Singapore
| | - Tien-En Tan
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore; Ophthalmology & Visual Sciences Academic Clinical Program (EYE ACP), Duke-NUS Medical School, Singapore
| | - Augustinus Laude
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Wei Kiong Ngo
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore
| | - Graham E Holder
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, National University Hospital, National University Health System, Singapore
| | - Xinyi Su
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, National University Hospital, National University Health System, Singapore
| | - Ta-Ching Chen
- Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan; Center of Frontier Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Nan-Kai Wang
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University, New York, NY, USA; Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan
| | - Eugene Yu-Chuan Kang
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan; Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chu-Hsuan Huang
- Department of Ophthalmology, Cathay General Hospital, Taipei, Taiwan
| | - Nuntachai Surawatsatien
- Center of Excellence in Retina, Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Phattrawan Pisuchpen
- Department of Ophthalmology and Division of Academic Affairs, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Tharikarn Sujirakul
- Department of Ophthalmology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | | | - Mandeep Singh
- Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, MD 21287, USA
| | - Bart Leroy
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium; Department of Ophthalmology, Ghent University Hospital, Ghent, Belgium
| | - Michel Michaelides
- Moorfields Eye Hospital, London, United Kingdom and UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ching-Yu Cheng
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Singapore National Eye Centre, Singapore Eye Research Institute, Singapore
| | - Li Jia Chen
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Hwei Wuen Chan
- Centre for Innovation & Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Ophthalmology, National University Hospital, National University Health System, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
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Murro V, Banfi S, Testa F, Iarossi G, Falsini B, Sodi A, Signorini S, Iolascon A, Russo R, Mucciolo DP, Caputo R, Bacci GM, Bargiacchi S, Turco S, Fortini S, Simonelli F. A multidisciplinary approach to inherited retinal dystrophies from diagnosis to initial care: a narrative review with inputs from clinical practice. Orphanet J Rare Dis 2023; 18:223. [PMID: 37525225 PMCID: PMC10388566 DOI: 10.1186/s13023-023-02798-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: 10/10/2022] [Accepted: 07/05/2023] [Indexed: 08/02/2023] Open
Abstract
BACKGROUND Non-syndromic inherited retinal dystrophies (IRDs) such as retinitis pigmentosa or Leber congenital amaurosis generally manifest between early childhood and late adolescence, imposing profound long-term impacts as a result of vision impairment or blindness. IRDs are highly heterogeneous, with often overlapping symptoms among different IRDs, and achieving a definite diagnosis is challenging. This narrative review provides a clinical overview of the non-syndromic generalized photoreceptor dystrophies, particularly retinitis pigmentosa and Leber congenital amaurosis. The clinical investigations and genetic testing needed to establish a diagnosis are outlined, and current management approaches are discussed, focusing on the importance of the involvement of an interdisciplinary team from diagnosis and initial care to long-term follow-up and support. RESULTS The effective management of IRDs requires a multidisciplinary, and ideally interdisciplinary, team of experts knowledgeable about IRDs, with experienced professionals from fields as diverse as ophthalmology, neuropsychiatry, psychology, neurology, genetics, orthoptics, developmental therapy, typhlology, occupational therapy, otolaryngology, and orientation and mobility specialties. Accurate clinical diagnosis encompasses a range of objective and subjective assessments as a prerequisite for the genetic testing essential in establishing an accurate diagnosis necessary for the effective management of IRDs, particularly in the era of gene therapies. Improvements in genome sequencing techniques, such as next-generation sequencing, have greatly facilitated the complex process of determining IRD-causing gene variants and establishing a molecular diagnosis. Genetic counseling is essential to help the individual and their family understand the condition, the potential risk for offspring, and the implications of a diagnosis on visual prognosis and treatment options. Psychological support for patients and caregivers is important at all stages of diagnosis, care, and rehabilitation and is an essential part of the multidisciplinary approach to managing IRDs. Effective communication throughout is essential, and the patient and caregivers' needs and expectations must be acknowledged and discussed. CONCLUSION As IRDs can present at an early age, clinicians need to be aware of the clinical signs suggesting visual impairment and follow up with multidisciplinary support for timely diagnoses to facilitate appropriate therapeutic or rehabilitation intervention to minimize vision loss.
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Affiliation(s)
- Vittoria Murro
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
- Eye Clinic, Careggi Teaching Hospital, Florence, Italy
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, NA, Italy
- Medical Genetics, Department of Precision Medicine, University of Campania Luigi Vanvitelli, Naples, Italy
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania Luigi Vanvitelli, Naples, Italy.
| | - Giancarlo Iarossi
- Department of Ophthalmology, Bambino Gesù Children's Hospital, Rome, Italy
| | - Benedetto Falsini
- Ophthalmology Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Andrea Sodi
- Eye Clinic, Careggi Teaching Hospital, Florence, Italy
| | - Sabrina Signorini
- Center of Child Neuro-Ophthalmology, IRCCS, Mondino Foundation, Pavia, Italy
| | - Achille Iolascon
- Medical Genetics Unit, Azienda Ospedaliera Universitaria Federico II, Naples, Italy
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Naples, Italy
| | - Roberta Russo
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Naples, Italy
| | - Dario Pasquale Mucciolo
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
- Ophthalmology Unit, San Jacopo Hospital, Pistoia, Italy
| | - Roberto Caputo
- Pediatric Ophthalmology Unit, A. Meyer Children's Hospital IRCCS, Florence, Italy
| | - Giacomo Maria Bacci
- Pediatric Ophthalmology Unit, A. Meyer Children's Hospital IRCCS, Florence, Italy
| | - Sara Bargiacchi
- Medical Genetics Unit, Ospedale Pediatrico Meyer, Florence, Italy
| | - Simona Turco
- National Centre of Services and Research for the Prevention of Blindness and Rehabilitation of the Visually Impaired, International Agency for the Prevention of Blindness-IAPB Italy Onlus, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Stefania Fortini
- National Centre of Services and Research for the Prevention of Blindness and Rehabilitation of the Visually Impaired, International Agency for the Prevention of Blindness-IAPB Italy Onlus, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania Luigi Vanvitelli, Naples, Italy
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Albakri A, Pisuchpen P, Capasso JE, Schneider A, Kopinsky S, Glaser T, Chiang JPW, Yomai AA, McNear D, Levin AV. Novel CRB1 pathogenic variant in Chuuk families with Leber congenital amaurosis. Am J Med Genet A 2023; 191:1007-1012. [PMID: 36595661 PMCID: PMC10262898 DOI: 10.1002/ajmg.a.63108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 01/05/2023]
Abstract
The purpose of this article is to determine the cause of Leber congenital amaurosis (LCA) in Chuuk state, Federated States of Micronesia (FSM). In this prospective observational case series, five patients with early-onset vision loss were examined in Chuuk state, FSM, during an ocular genetics visit to study the elevated incidence of microphthalmia. Because of their low vision these patients were incorrectly assumed to have microphthalmia. A complete ophthalmological exam established a clinical diagnosis of LCA. Candidate gene exons were sequenced with a targeted retinal dystrophy panel. Five subjects in three related families were diagnosed with LCA. All five were from Tonoas Island, within the Chuuk Lagoon, with ages ranging from 6 months to 16 years. DNA sequencing of affected individuals revealed a homozygous CRB1 NM_201253.3:c.3134del pathogenic variant, which was heterozygous in their parents. CRB1 genotypes were confirmed by a PCR restriction assay. We report identification of a founder pathogenic variant in CRB1 responsible for autosomal recessive LCA in this isolated community. This discovery will lead to appropriate recurrence risk counseling.
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Affiliation(s)
- Amani Albakri
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Division of Pediatric Ophthalmology, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Phattrawan Pisuchpen
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, Thailand
| | - Jenina E. Capasso
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
| | - Adele Schneider
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Division of Genetics, Einstein Healthcare Network, Philadelphia, Pennsylvania, USA
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Sarina Kopinsky
- Division of Genetics, Einstein Healthcare Network, Philadelphia, Pennsylvania, USA
| | - Tom Glaser
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, USA
| | | | | | - Donna McNear
- Independent Educational Consultant, Cambridge, Minnesota, USA
| | - Alex V. Levin
- Pediatric and Ocular Genetics, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Challenges and Opportunities in the Genetic Analysis of Inherited Retinal Dystrophies in Africa, a Literature Review. J Pers Med 2023; 13:jpm13020239. [PMID: 36836473 PMCID: PMC9964248 DOI: 10.3390/jpm13020239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/20/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023] Open
Abstract
Inherited retinal dystrophies (IRDs) are a global problem that is largely unaddressed, especially in Africa. Black indigenous Africans are rarely represented in research that develops genetic tests and genetic therapies for IRDs, yet their genomes are more diverse. The aim of this literature review is to synthesize information on the IRD genetic research conducted among indigenous black Africans to identify challenges and opportunities for progress. PubMed was searched to identify empirical publications reporting the genetic analysis of IRDs among indigenous Africans. A total of 11 articles were selected for the review. Based on the information in the articles, the main genetic testing methods in use include next-generation, whole exome, and Sanger sequencing. The main IRDs characterized by the genetic tests include retinitis pigmentosa, Leber Congenital Amaurosis, Stagardt disease, and cone dystrophy. Examples of implicated genes include MERTK, GUCY2D, ABCA4, and KCNV2 for the four IRDs, respectively. Research activities on the genetics of IRDs are generally scanty in Africa. Even in South Africa and North Africa where some research activities were noted, only a few indigenous black Africans were included in the study cohorts. There is an urgent need for genetic research on IRDs, especially in East, Central, and West Africa.
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Kolesnikova M, Lima de Carvalho JR, Parmann R, Kim AH, Mahajan VB, Tsang SH, Sparrow JR. Chorioretinal atrophy following voretigene neparvovec despite the presence of fundus autofluorescence. Mol Genet Genomic Med 2022; 10:e2038. [PMID: 36225124 PMCID: PMC9651599 DOI: 10.1002/mgg3.2038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/06/2022] [Accepted: 07/19/2022] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION Leber congenital amaurosis (LCA) type 2, due to disease-causing variants in RPE65, is characterized by severe visual loss in early infancy. Current treatments include voretigene neparvovec-rzyl (VN) for RPE65-associated LCA. Herein, we present the long-term follow-up of a patient treated with VN using quantitative autofluorescence (488 nm excitation). CASE REPORT A 9-year-old girl with a diagnosis of LCA with biallelic variants in RPE65 presented for evaluation. The patient underwent VN treatment at the age of 11. The patient returned to clinic at age of 19 at which time imaging revealed evidence of chorioretinal atrophy. Quantitative autofluorescence performed prior to gene therapy and at 6- and 8-year follow-up revealed a central area of fundus autofluorescence. DISCUSSION This case report demonstrates acquisition of fundus autofluorescence at 6- and 8-year follow-up despite the development of chorioretinal atrophy.
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Affiliation(s)
- Masha Kolesnikova
- Edward S. Harkness Eye InstituteNew York‐Presbyterian HospitalNew YorkNew YorkUSA
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of OphthalmologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
- College of Medicine at the State University of New York at Downstate Medical CenterBrooklynNew YorkUSA
| | - Jose Ronaldo Lima de Carvalho
- Department of Ophthalmology, Hospital das Clínicas de Pernambuco, Empresa Brasileira de Serviços HospitalaresFederal University of PernambucoRecifeBrazil
| | - Rait Parmann
- Edward S. Harkness Eye InstituteNew York‐Presbyterian HospitalNew YorkNew YorkUSA
| | - Angela H. Kim
- Edward S. Harkness Eye InstituteNew York‐Presbyterian HospitalNew YorkNew YorkUSA
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of OphthalmologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
- College of Medicine at the State University of New York at Downstate Medical CenterBrooklynNew YorkUSA
| | - Vinit B. Mahajan
- Byers Eye Institute, Molecular Surgery ProgramStanford UniversityPalo AltoCaliforniaUSA
| | - Stephen H. Tsang
- Edward S. Harkness Eye InstituteNew York‐Presbyterian HospitalNew YorkNew YorkUSA
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of OphthalmologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
- Department of Pathology & Cell BiologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Janet R. Sparrow
- Edward S. Harkness Eye InstituteNew York‐Presbyterian HospitalNew YorkNew YorkUSA
- Department of Pathology & Cell BiologyColumbia University Irving Medical CenterNew YorkNew YorkUSA
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7
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Duan W, Zhou T, Jiang H, Zhang M, Hu M, Zhang L. A novel nonsense variant (c.1499C>G) in CRB1 caused Leber congenital amaurosis-8 in a Chinese family and a literature review. BMC Med Genomics 2022; 15:197. [PMID: 36115989 PMCID: PMC9482190 DOI: 10.1186/s12920-022-01356-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 09/09/2022] [Indexed: 12/04/2022] Open
Abstract
Background Leber’s congenital amaurosis (LCA) is a severe hereditary retinopathy disease that is characterized by early and severe reduction of vision, nystagmus, and sluggish or absent pupillary responses. To date, the pathogenesis of LCA remains unclear, and the majority of cases are caused by autosomal recessive inheritance. In this study, we explored the variant in the Crumbs homologue 1 (CRB1) gene in a Chinese family with LCA.
Methods We conducted comprehensive ocular examinations and collected 5 ml of blood samples from members of a Chinese family with LCA. A pathogenic variant was identified by capturing (the panel in NGS) and Sanger sequencing validation. Results A nonsense variant (c.1499C>G) in the 6th exon of CRB1 gene in a Chinese family with LCA was identified, which predicted a change in the protein p. S500*, may lead to loss of gene function. We summarized the 76 variants reported thus far in CRB1 that caused LCA8. Conclusions This study reported a novel variant c.1499C>G (p. S500*) of the CRB1 gene occurred in a Chinese family with LCA, thus expanding the spectrum of CRB1 variants causing LCA.
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8
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Girach A, Audo I, Birch DG, Huckfeldt RM, Lam BL, Leroy BP, Michaelides M, Russell SR, Sallum JM, Stingl K, Tsang SH, Yang P. RNA-based therapies in inherited retinal diseases. Ther Adv Ophthalmol 2022; 14:25158414221134602. [PMID: 36388727 PMCID: PMC9643766 DOI: 10.1177/25158414221134602] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/05/2022] [Indexed: 11/10/2023] Open
Abstract
Inherited retinal diseases (IRDs) are a genetically and phenotypically heterogeneous group of genetic eye disorders. There are more than 300 disease entities, and together this group of disorders affects millions of people globally and is a frequent cause of blindness or low-vision certification. However, each type is rare or ultra-rare. Characteristically, the impaired vision in IRDs is due to retinal photoreceptor dysfunction and loss resulting from mutation in a gene that codes for a retinal protein. Historically, IRDs have been considered incurable and individuals living with these blinding conditions could be offered only supportive care. However, the treatment landscape for IRDs is beginning to evolve. Progress is being made, driven by improvements in understanding of genotype-phenotype relationships, through advances in molecular genetic testing and retinal imaging. Alongside this expanding knowledge of IRDs, the current era of precision medicine is fueling a growth in targeted therapies. This has resulted in the first treatment for an IRD being approved. Several other therapies are currently in development in the IRD space, including RNA-based therapies, gene-based therapies (such as augmentation therapy and gene editing), cell therapy, visual prosthetics, and optogenetics. RNA-based therapies are a novel approach within precision medicine that have demonstrated success, particularly in rare diseases. Three antisense oligonucleotides (AONs) are currently in development for the treatment of specific IRD subtypes. These RNA-based therapies bring several key advantages in the setting of IRDs, and the potential to bring meaningful vision benefit to individuals living with inherited blinding disorders. This review will examine the increasing breadth and relevance of RNA-based therapies in clinical medicine, explore the key features that make AONs suitable for treating genetic eye diseases, and provide an overview of the three-leading investigational AONs in clinical trials.
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Affiliation(s)
- Aniz Girach
- ProQR Therapeutics, Zernikedreef 9, 2333 CK
Leiden, the Netherlands
| | - Isabelle Audo
- Centre Hospitalier National d’Ophtalmologie des
Quinze-Vingts, Centre de référence maladies rares REFERET and INSERM-DHOS
CIC 1423, CHNO des Quinze-Vingts, Paris, France
- Institute of Ophthalmology, University College
London, London, UK
- Sorbonne Université, INSERM, CNRS, Institut de
la Vision, Paris, France
| | | | - Rachel M. Huckfeldt
- Department of Ophthalmology, Harvard Medical
School, Massachusetts Eye and Ear Infirmary, Boston, MA, USA
| | - Byron L. Lam
- Bascom Palmer Eye Institute, University of
Miami Miller School of Medicine, Miami, FL, USA
| | - Bart P. Leroy
- Department of Ophthalmology & Center for
Medical Genetics, Ghent University Hospital & Ghent University, Ghent,
Belgium
- Division of Ophthalmology & Center for
Cellular & Molecular Therapeutics, The Children’s Hospital of
Philadelphia, Philadelphia, PA, USA
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University
College London and Moorfields Eye Hospital, London, UK
| | - Stephen R. Russell
- The University of Iowa Institute for Vision
Research, University of Iowa, Iowa City, IA, USA
| | - Juliana M.F. Sallum
- Department of Ophthalmology, Universidade
Federal de São Paulo, São Paulo, Brazil
- Instituto de Genética Ocular, São Paulo,
Brazil
| | - Katarina Stingl
- Center for Ophthalmology, University Eye
Hospital, University of Tübingen, Tübingen, Germany
- Center for Rare Eye Diseases, University of
Tübingen, Tübingen, Germany
| | - Stephen H. Tsang
- Jonas Children’s Vision Care and Bernard and
Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Vagelos
College of Physicians and Surgeons, Columbia University, New York, NY,
USA
- Edward S. Harkness Eye Institute, New
York-Presbyterian Hospital, New York, NY, USA
| | - Paul Yang
- Casey Eye Institute, Oregon Health &
Science University, Portland, OR, USA
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9
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Simonelli F, Sodi A, Falsini B, Bacci G, Iarossi G, Di Iorio V, Giorgio D, Placidi G, Andrao A, Reale L, Fiorencis A, Aoun M. Care Pathway of RPE65-Related Inherited Retinal Disorders from Early Symptoms to Genetic Counseling: A Multicenter Narrative Medicine Project in Italy. Clin Ophthalmol 2021; 15:4591-4605. [PMID: 34880596 PMCID: PMC8648274 DOI: 10.2147/opth.s331218] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/11/2021] [Indexed: 11/28/2022] Open
Abstract
Purpose Timely detection and multidisciplinary management of RPE65-related inherited retinal disorders (IRDs) can significantly improve both disease management and patient care. Thus, this Narrative Medicine (NM) project aimed to investigate the evolution of the care pathway and the expectations on genetic counseling and gene therapy by patients, caregivers, and healthcare professionals. Patients and Methods This project was conducted between July and December 2020, involving five Italian eye clinics specialized in IRDs, targeted pediatric and adult patients, their caregivers, attending retinologists and multidisciplinary healthcare professionals. Narratives and parallel charts, together with a sociodemographic survey, were collected through the project webpage. In-depth interviews were conducted with Patient Association (PA) members and multidisciplinary healthcare professionals. All data were entered into the Nvivo Software for coding and analysis. Results Three pediatric and five adult patients with early-onset RPE65-related IRDs as well as eight caregivers were enrolled; 11 retinologists globally wrote 27 parallel charts; in-depth interviews were done with five multidisciplinary healthcare professionals and one PA member. Early diagnosis remains challenging, and patients reported to have changed up to 10 healthcare professionals before accessing their specialized center. Despite the oftentimes lack of awareness of patients and caregivers on the purpose of genetic testing, participants generally consider gene therapy as a therapeutic chance and a historic breakthrough for the management of RPE65-related IRDs. Well-organized networks to support the patient’s referral to specialized centers – as well as a proper communication of the clinical and genetic diagnosis and the multidisciplinary approach – emerge as crucial aspects in facilitating an early diagnosis and management and a timely initiation of the rehabilitation pathway. Conclusion The project investigated the RPE65-related IRDs care pathway while integrating the different perspectives involved through NM. The analysis explored the patient’s pathway in Italy and confirmed the need for a well-organized network and multidisciplinary care while highlighting several preliminary areas of improvement in the management of RPE65-related IRDs.
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Affiliation(s)
- Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "L. Vanvitelli", Naples, Italy
| | - Andrea Sodi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Benedetto Falsini
- UOC Oftalmologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,Dipartimento Testa-collo e organi di senso, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Giacomo Bacci
- Paediatric Ophthalmology Unit, Children's Hospital "A. Meyer", University of Florence, Florence, Italy
| | - Giancarlo Iarossi
- Ophthalmology Department, Bambino Gesù IRCCS Paediatric Hospital, Rome, Italy
| | - Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "L. Vanvitelli", Naples, Italy
| | - Dario Giorgio
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Giorgio Placidi
- UOC Oftalmologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy.,Dipartimento Testa-collo e organi di senso, Università Cattolica del Sacro Cuore, Rome, Italy
| | | | - Luigi Reale
- Healthcare Department, Fondazione ISTUD, Milan, Italy
| | | | - Manar Aoun
- Medical Department, Novartis Farma, Origgio, Italy
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10
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Kalatzis V, Roux AF, Meunier I. Molecular Therapy for Choroideremia: Pre-clinical and Clinical Progress to Date. Mol Diagn Ther 2021; 25:661-675. [PMID: 34661884 DOI: 10.1007/s40291-021-00558-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2021] [Indexed: 12/01/2022]
Abstract
Choroideremia is an inherited retinal disease characterised by a degeneration of the light-sensing photoreceptors, supporting retinal pigment epithelium and underlying choroid. Patients present with the same symptoms as those with classic rod-cone dystrophy: (1) night blindness early in life; (2) progressive peripheral visual field loss, and (3) central vision decline with a slow progression to legal blindness. Choroideremia is monogenic and caused by mutations in CHM. Eight clinical trials (three phase 1/2, four phase 2, and one phase 3) have started (four of which are already finished) to evaluate the therapeutic efficacy of gene supplementation mediated by subretinal delivery of an adeno-associated virus serotype 2 (AAV2/2) vector expressing CHM. Furthermore, one phase 1 clinical trial has been initiated to evaluate the efficiency of a novel AAV variant to deliver CHM to the outer retina following intravitreal delivery. Lastly, a non-viral-mediated CHM replacement strategy is currently under development, which could lead to a future clinical trial. Here, we summarise the rationale behind these various studies, as well as any results published to date. The diversity of these trials currently places choroideremia at the forefront of the retinal gene therapy field. As a consequence, the trial outcomes, regardless of the results, have the potential to change the landscape of gene supplementation for inherited retinal diseases.
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Affiliation(s)
- Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.
| | - Anne-Françoise Roux
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,National Reference Centre for Inherited Sensory Diseases, University of Montpellier, CHU Montpellier, Montpellier, France
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11
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Roman AJ, Cideciyan AV, Wu V, Garafalo AV, Jacobson SG. Full-field stimulus testing: Role in the clinic and as an outcome measure in clinical trials of severe childhood retinal disease. Prog Retin Eye Res 2021; 87:101000. [PMID: 34464742 DOI: 10.1016/j.preteyeres.2021.101000] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/24/2021] [Accepted: 08/27/2021] [Indexed: 12/27/2022]
Abstract
Disease mechanisms have become better understood in previously incurable forms of early-onset severe retinal dystrophy, such as Leber congenital amaurosis (LCA). This has led to novel treatments and clinical trials that have shown some success. Standard methods to measure vision were difficult if not impossible to perform in severely affected patients with low vision and nystagmus. To meet the need for visual assays, we devised a psychophysical method, which we named full-field stimulus testing (FST). From early versions based on an automated perimeter, we advanced FST to a more available light-emitting diode platform. The journey from invention to use of such a technique in our inherited retinal degeneration clinic is reviewed and many of the lessons learned over the 15 years of application of FST are explained. Although the original purpose and application of FST was to quantify visual thresholds in LCA, there are rare opportunities for FST also to be used beyond LCA to measure aspects of vision in other inherited retinal degenerations; examples are given. The main goal of the current review, however, remains to enable investigators studying and treating LCA to understand how to best use FST and how to reduce artefact and confounding complexities so the test results become more valuable to the understanding of LCA diseases and results of novel interventions.
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Affiliation(s)
- Alejandro J Roman
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Artur V Cideciyan
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Vivian Wu
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Alexandra V Garafalo
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Samuel G Jacobson
- Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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12
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Huang CH, Yang CM, Yang CH, Hou YC, Chen TC. Leber's Congenital Amaurosis: Current Concepts of Genotype-Phenotype Correlations. Genes (Basel) 2021; 12:genes12081261. [PMID: 34440435 PMCID: PMC8392113 DOI: 10.3390/genes12081261] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/15/2021] [Accepted: 08/18/2021] [Indexed: 12/26/2022] Open
Abstract
Leber’s congenital amaurosis (LCA), one of the most severe inherited retinal dystrophies, is typically associated with extremely early onset of visual loss, nystagmus, and amaurotic pupils, and is responsible for 20% of childhood blindness. With advances in molecular diagnostic technology, the knowledge about the genetic background of LCA has expanded widely, while disease-causing variants have been identified in 38 genes. Different pathogenetic mechanisms have been found among these varieties of genetic mutations, all of which result in the dysfunction or absence of their encoded proteins participating in the visual cycle. Hence, the clinical phenotypes also exhibit extensive heterogenicity, including the course of visual impairment, involvement of the macular area, alteration in retinal structure, and residual function of the diseased photoreceptor. By reviewing the clinical course, fundoscopic images, optical coherent tomography examination, and electroretinogram, genotype-phenotype correlations could be established for common genetic mutations in LCA, which would benefit the timing of the diagnosis and thus promote early intervention. Gene therapy is promising in the management of LCA, while several clinical trials are ongoing and preliminary success has been announced, focusing on RPE65 and other common disease-causing genes. This review provides an update on the genetics, clinical examination findings, and genotype-phenotype correlations in the most well-established causative genetic mutations of LCA.
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Affiliation(s)
- Chu-Hsuan Huang
- Department of Ophthalmology, Cathay General Hospital, Taipei 106, Taiwan; (C.-H.H.); (Y.-C.H.)
| | - Chung-May Yang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-M.Y.); (C.-H.Y.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Chang-Hao Yang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-M.Y.); (C.-H.Y.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Yu-Chih Hou
- Department of Ophthalmology, Cathay General Hospital, Taipei 106, Taiwan; (C.-H.H.); (Y.-C.H.)
| | - Ta-Ching Chen
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 100, Taiwan; (C.-M.Y.); (C.-H.Y.)
- Correspondence: ; Tel.: +886-2-23123456
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13
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Medina G, Perry J, Oza A, Kenna M. Hiding in plain sight: genetic deaf-blindness is not always Usher syndrome. Cold Spring Harb Mol Case Stud 2021; 7:mcs.a006088. [PMID: 34021019 PMCID: PMC8327880 DOI: 10.1101/mcs.a006088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 05/03/2021] [Indexed: 11/25/2022] Open
Abstract
Hearing loss (HL) is the most common congenital sensory impairment. Usher syndrome (USH) is the leading genetic etiology of congenital deafness combined with progressive vision loss, and individuals presenting with these symptoms are often assumed to have USH. This can be an erroneous assumption, as there are additional genetic causes of deaf-blindness. Our objective is to describe and accurately diagnose non-USH genetic causes of deaf-blindness. We present three children with hearing and vision loss with clinical and genetic findings suggestive of USH. However, ongoing clinical assessment did not completely support an USH diagnosis, and exome analysis was pursued for all three individuals. Updated genetic testing showed pathogenic variants in ALMS1 in the first individual and TUBB4B in the second and third. Although HL in all three was consistent with USH type 2, vision impairment with retinal changes was noted by age 2 yr, which is unusual for USH. In all three the updated genotype more accurately fit the clinical phenotype. Because USH is the most common form of genetic deaf-blindness, individuals with HL, early vision impairment, and retinal dysfunction are often assumed to have USH. However, additional genes associated with HL and retinal impairment include ALMS1, TUBB4B, CEP78, ABHD12, and PRPS1. Accurate genetic diagnosis is critical to these individuals’ understanding of their genetic conditions, prognosis, vision and hearing loss management, and future access to molecular therapies. If clinically or genetically USH seems uncertain, updated genetic testing for non-USH genes is essential.
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Affiliation(s)
- Genevieve Medina
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - Julia Perry
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Boston, Massachusetts 02115, USA
| | - Andrea Oza
- Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Cambridge, Massachusetts 02139, USA.,Invitae, San Francisco, California 94103, USA
| | - Margaret Kenna
- Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts 02115, USA
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14
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Hong Y, Luo Y. Zebrafish Model in Ophthalmology to Study Disease Mechanism and Drug Discovery. Pharmaceuticals (Basel) 2021; 14:ph14080716. [PMID: 34451814 PMCID: PMC8400593 DOI: 10.3390/ph14080716] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/14/2022] Open
Abstract
Visual impairment and blindness are common and seriously affect people’s work and quality of life in the world. Therefore, the effective therapies for eye diseases are of high priority. Zebrafish (Danio rerio) is an alternative vertebrate model as a useful tool for the mechanism elucidation and drug discovery of various eye disorders, such as cataracts, glaucoma, diabetic retinopathy, age-related macular degeneration, photoreceptor degeneration, etc. The genetic and embryonic accessibility of zebrafish in combination with a behavioral assessment of visual function has made it a very popular model in ophthalmology. Zebrafish has also been widely used in ocular drug discovery, such as the screening of new anti-angiogenic compounds or neuroprotective drugs, and the oculotoxicity test. In this review, we summarized the applications of zebrafish as the models of eye disorders to study disease mechanism and investigate novel drug treatments.
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Affiliation(s)
| | - Yan Luo
- Correspondence: ; Tel.: +86-020-87335931
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15
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Chen HY, Lehmann OJ, Swaroop A. Genetics and therapy for pediatric eye diseases. EBioMedicine 2021; 67:103360. [PMID: 33975254 PMCID: PMC8122153 DOI: 10.1016/j.ebiom.2021.103360] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/29/2021] [Accepted: 04/12/2021] [Indexed: 12/26/2022] Open
Abstract
Ocular morphogenesis in vertebrates is a highly organized process, orchestrated largely by intrinsic genetic programs that exhibit stringent spatiotemporal control. Alternations in these genetic instructions can lead to hereditary or nonhereditary congenital disorders, a major cause of childhood visual impairment, and contribute to common late-onset blinding diseases. Currently, limited treatment options exist for clinical phenotypes involving eye development. This review summarizes recent advances in our understanding of early-onset ocular disorders and highlights genetic complexities in development and diseases, specifically focusing on coloboma, congenital glaucoma and Leber congenital amaurosis. We also discuss innovative paradigms for potential therapeutic modalities.
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Affiliation(s)
- Holly Y Chen
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, MSC0610, 6 Center Drive, Bethesda, MD 20892 USA.
| | - Ordan J Lehmann
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Canada; Department of Medical Genetics, University of Alberta, Edmonton, Canada.
| | - Anand Swaroop
- Neurobiology-Neurodegeneration & Repair Laboratory, National Eye Institute, National Institutes of Health, MSC0610, 6 Center Drive, Bethesda, MD 20892 USA.
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16
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Photoreceptor phosphodiesterase (PDE6): activation and inactivation mechanisms during visual transduction in rods and cones. Pflugers Arch 2021; 473:1377-1391. [PMID: 33860373 DOI: 10.1007/s00424-021-02562-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/27/2021] [Accepted: 03/30/2021] [Indexed: 01/16/2023]
Abstract
Rod and cone photoreceptors of the vertebrate retina utilize cGMP as the primary intracellular messenger for the visual signaling pathway that converts a light stimulus into an electrical response. cGMP metabolism in the signal-transducing photoreceptor outer segment reflects the balance of cGMP synthesis (catalyzed by guanylyl cyclase) and degradation (catalyzed by the photoreceptor phosphodiesterase, PDE6). Upon light stimulation, rapid activation of PDE6 by the heterotrimeric G-protein (transducin) triggers a dramatic drop in cGMP levels that lead to cell hyperpolarization. Following cessation of the light stimulus, the lifetime of activated PDE6 is also precisely regulated by additional processes. This review summarizes recent advances in the structural characterization of the rod and cone PDE6 catalytic and regulatory subunits in the context of previous biochemical studies of the enzymological properties and allosteric regulation of PDE6. Emphasis is given to recent advances in understanding the structural and conformational changes underlying the mechanism by which the activated transducin α-subunit binds to-and relieves inhibition of-PDE6 catalysis that is controlled by its intrinsically disordered, inhibitory γ-subunit. The role of the regulator of G-protein signaling 9-1 (RGS9-1) in regulating the lifetime of the transducin-PDE6 is also briefly covered. The therapeutic potential of pharmacological compounds acting as inhibitors or activators targeting PDE6 is discussed in the context of inherited retinal diseases resulting from mutations in rod and cone PDE6 genes as well as other inherited defects that arise from excessive cGMP accumulation in retinal photoreceptor cells.
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17
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Jaroszynska N, Harding P, Moosajee M. Metabolism in the Zebrafish Retina. J Dev Biol 2021; 9:10. [PMID: 33804189 PMCID: PMC8006245 DOI: 10.3390/jdb9010010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/08/2021] [Accepted: 03/11/2021] [Indexed: 12/12/2022] Open
Abstract
Retinal photoreceptors are amongst the most metabolically active cells in the body, consuming more glucose as a metabolic substrate than even the brain. This ensures that there is sufficient energy to establish and maintain photoreceptor functions during and after their differentiation. Such high dependence on glucose metabolism is conserved across vertebrates, including zebrafish from early larval through to adult retinal stages. As the zebrafish retina develops rapidly, reaching an adult-like structure by 72 hours post fertilisation, zebrafish larvae can be used to study metabolism not only during retinogenesis, but also in functionally mature retinae. The interplay between rod and cone photoreceptors and the neighbouring retinal pigment epithelium (RPE) cells establishes a metabolic ecosystem that provides essential control of their individual functions, overall maintaining healthy vision. The RPE facilitates efficient supply of glucose from the choroidal vasculature to the photoreceptors, which produce metabolic products that in turn fuel RPE metabolism. Many inherited retinal diseases (IRDs) result in photoreceptor degeneration, either directly arising from photoreceptor-specific mutations or secondary to RPE loss, leading to sight loss. Evidence from a number of vertebrate studies suggests that the imbalance of the metabolic ecosystem in the outer retina contributes to metabolic failure and disease pathogenesis. The use of larval zebrafish mutants with disease-specific mutations that mirror those seen in human patients allows us to uncover mechanisms of such dysregulation and disease pathology with progression from embryonic to adult stages, as well as providing a means of testing novel therapeutic approaches.
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Affiliation(s)
| | - Philippa Harding
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK;
| | - Mariya Moosajee
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK;
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
- The Francis Crick Institute, London NW1 1AT, UK
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18
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Abad-Morales V, Wert A, Ruiz Gómez MÁ, Navarro R, Pomares E. New Insights on the Genetic Basis Underlying SHILCA Syndrome: Characterization of the NMNAT1 Pathological Alterations Due to Compound Heterozygous Mutations and Identification of a Novel Alternative Isoform. Int J Mol Sci 2021; 22:2262. [PMID: 33668384 PMCID: PMC7956282 DOI: 10.3390/ijms22052262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/18/2021] [Accepted: 02/21/2021] [Indexed: 01/26/2023] Open
Abstract
This study aims to genetically characterize a two-year-old patient suffering from multiple systemic abnormalities, including skeletal, nervous and developmental involvements and Leber congenital amaurosis (LCA). Genetic screening by next-generation sequencing identified two heterozygous pathogenic variants in nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) as the molecular cause of the disease: c.439+5G>T and c.299+526_*968dup.This splice variant has never been reported to date, whereas pathogenic duplication has recently been associated with cases displaying an autosomal recessive disorder that includes a severe form of spondylo-epiphyseal dysplasia, sensorineural hearing loss, intellectual disability and LCA (SHILCA), as well as some brain anomalies. Our patient presented clinical manifestations which correlated strongly with this reported syndrome. To further study the possible transcriptional alterations resulting from these mutations, mRNA expression assays were performed in the patient and her father. The obtained results detected aberrant alternative transcripts and unbalanced levels of expression, consistent with severe systemic involvement. Moreover, these analyses also detected a novel NMNAT1 isoform, which is variably expressed in healthy human tissues. Altogether, these findings represent new evidence of the correlation of NMNAT1 and SHILCA syndrome, and provide additional insights into the healthy and pathogenic expression of this gene.
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Affiliation(s)
- Víctor Abad-Morales
- Fundació de Recerca de l’Institut de Microcirurgia Ocular, 08035 Barcelona, Spain; (A.W.); (R.N.)
- Department of Genetics, Institut de Microcirurgia Ocular (IMO), 08035 Barcelona, Spain
| | - Ana Wert
- Fundació de Recerca de l’Institut de Microcirurgia Ocular, 08035 Barcelona, Spain; (A.W.); (R.N.)
- Department of Pediatric Ophthalmology, Strabismus and Neurophthalmology, Institut de Microcirurgia Ocular (IMO), 08035 Barcelona, Spain
| | - María Ángeles Ruiz Gómez
- Pediatric Metabolic Unit and Neuropediatrics, Hospital Universitari Son Espases, 07120 Palma de Mallorca, Spain;
| | - Rafael Navarro
- Fundació de Recerca de l’Institut de Microcirurgia Ocular, 08035 Barcelona, Spain; (A.W.); (R.N.)
- Department of Retina, Institut de Microcirurgia Ocular (IMO), 08035 Barcelona, Spain
| | - Esther Pomares
- Fundació de Recerca de l’Institut de Microcirurgia Ocular, 08035 Barcelona, Spain; (A.W.); (R.N.)
- Department of Genetics, Institut de Microcirurgia Ocular (IMO), 08035 Barcelona, Spain
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Leber Congenital Amaurosis Due to GUCY2D Mutations: Longitudinal Analysis of Retinal Structure and Visual Function. Int J Mol Sci 2021; 22:ijms22042031. [PMID: 33670772 PMCID: PMC7922686 DOI: 10.3390/ijms22042031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/12/2021] [Accepted: 02/15/2021] [Indexed: 12/22/2022] Open
Abstract
Gene augmentation therapy is being planned for GUCY2D-associated Leber congenital amaurosis (LCA). To increase our understanding of the natural history of GUCY2D-LCA, patients were evaluated twice with an interval of 4 to 7 years between visits using safety and efficacy outcome measures previously determined to be useful for monitoring this disorder. In this group of molecularly-identified LCA patients (n = 10; ages 7–37 years at first visit), optical coherence tomography (OCT) was used to measure foveal cone outer nuclear layer (ONL) thickness and rod ONL at a superior retinal locus. Full-field stimulus testing (FST) with chromatic stimuli in dark- and light-adapted states was used to assay rod and cone vision. Changes in OCT and FST over the interval were mostly attributable to inter-visit variability. There were no major negative changes in structure or function across the cohort and over the intervals studied. Variation in severity of disease expression between patients occurs; however, despite difficulties in quantifying structure and function in such seriously visually impaired individuals with nystagmus, the present work supports the use of OCT as a safety outcome and FST as an efficacy outcome in a clinical trial of GUCY2D-LCA. A wide age spectrum for therapy was confirmed, and there was relative stability of structure and function during a typical time interval for clinical trials.
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Sunaric Megevand G, Bron AM. Personalising surgical treatments for glaucoma patients. Prog Retin Eye Res 2020; 81:100879. [PMID: 32562883 DOI: 10.1016/j.preteyeres.2020.100879] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/08/2020] [Accepted: 06/12/2020] [Indexed: 02/06/2023]
Abstract
Surgical treatments for glaucoma have relied for decades on traditional filtering surgery such as trabeculectomy and, in more challenging cases, tubes. Antifibrotics were introduced to improve surgical success in patients at increased risk of failure but have been shown to be linked to a greater incidence of complications, some being potentially vision-threatening. As our understanding of glaucoma and its early diagnosis have improved, a more individualised management has been suggested. Recently the term "precision medicine" has emerged as a new concept of an individualised approach to disease management incorporating a wide range of individual data in the choice of therapeutic modalities. For glaucoma surgery, this involves evaluation of the right timing, individual risk factors, targeting the correct anatomical and functional outflow pathways and appropriate prevention of scarring. As a consequence, there is an obvious need for better knowledge of anatomical and functional pathways and for more individualised surgical approaches with new, less invasive and safer techniques allowing for earlier intervention. With the recent advent of minimally invasive glaucoma surgery (MIGS) a large number of novel devices have been introduced targeting potential new sites of the outflow pathway for lowering intraocular pressure (IOP). Their popularity is growing in view of the relative surgical simplicity and apparent lack of serious side effects. However, these new surgical techniques are still in an era of early experiences, short follow-up and lack of evidence of their superiority in safety and cost-effectiveness over the traditional methods. Each year several new devices are introduced while others are withdrawn from the market. Glaucoma continues to be the primary cause of irreversible blindness worldwide and access to safe and efficacious treatment is a serious problem, particularly in the emerging world where the burden of glaucoma-related blindness is important and concerning. Early diagnosis, individualised treatment and, very importantly, safe surgical management should be the hallmarks of glaucoma treatment. However, there is still need for a better understanding of the disease, its onset and progression, the functional and structural elements of the outflow pathways in relation to the new devices as well as their long-term IOP-lowering efficacy and safety. This review discusses current knowledge and the future need for personalised glaucoma surgery.
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Affiliation(s)
- Gordana Sunaric Megevand
- Clinical Eye Research Centre Memorial Adolphe de Rothschild, Geneva, Switzerland; Centre Ophtalmologique de Florissant, Geneva, Switzerland.
| | - Alain M Bron
- Department of Ophthalmology, University Hospital, Dijon, France; Centre des Sciences du Goût et de l'Alimentation, AgroSup Dijon, CNRS, INRAE, Université Bourgogne Franche-Comté, F-21000, Dijon, France
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Switonski M. Impact of gene therapy for canine monogenic diseases on the progress of preclinical studies. J Appl Genet 2020; 61:179-186. [PMID: 32189222 PMCID: PMC7148265 DOI: 10.1007/s13353-020-00554-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/24/2020] [Accepted: 03/09/2020] [Indexed: 12/31/2022]
Abstract
Rapid progress in knowledge of the organization of the dog genome has facilitated the identification of the mutations responsible for numerous monogenic diseases, which usually present a breed-specific distribution. The majority of these diseases have clinical and molecular counterparts in humans. The affected dogs have thus become valuable models for preclinical studies of gene therapy for problems such as eye diseases, immunodeficiency, lysosomal storage diseases, hemophilia, and muscular dystrophy. Successful gene therapies in dogs have significantly contributed to decisions to run clinical trials for several human diseases, such as Leber's congenital amaurosis 2-LCA2 (caused by a mutation of RPE65), X-linked retinitis pigmentosa-XLRP (caused by mutation RPGR), and achromatopsia (caused by mutation of CNGB3). Promising results were also obtained for canine as follows: hemophilia (A and B), mucopolysaccharidoses (MPS I, MPS IIIB, MPS VII), leukocyte adhesion deficiency (CLAD), and muscular dystrophy (a counterpart of human Duchenne dystrophy). Present knowledge on molecular background of canine monogenic diseases and their successful gene therapies prove that dogs have an important contribution to preclinical studies.
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Affiliation(s)
- Marek Switonski
- Department of Genetics and Animal Breeding, Poznan University of Life Sciences, Poznan, Poland.
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