1
|
Tao J, Luo J, Li K, Yang R, Lin Y, Ge J. Comprehensive genetic analysis uncovers the mutational spectrum of MFRP and its genotype-phenotype correlation in a large cohort of Chinese microphthalmia patients. Gene 2024; 926:148647. [PMID: 38848879 DOI: 10.1016/j.gene.2024.148647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/21/2024] [Accepted: 06/03/2024] [Indexed: 06/09/2024]
Abstract
PURPOSE Microphthalmia is a severe congenital ocular disease featured by abnormal ocular development. The aim of this study was to detail the genetic and clinical characteristics of a large cohort of Chinese patients with microphthalmia related to MFRP variants, focusing on uncovering genotype-phenotype correlations. METHODS Fifty microphthalmia patients from 44 unrelated Chinese families were recruited. Whole-exome sequencing (WES) was conducted to analyze the coding regions and adjacent intronic regions of MFRP. Axial lengths (AL) were measured for all probands and available family members. Protein structures of mutations with high frequency in our cohort were predicted. The genotype-phenotype correlations were explored by statistical analysis. RESULTS Sixteen MFRP variants were detected in 17 families, accounting for 38.64 % of all microphthalmia families. There were 9 novel mutations (c.427+1G>C, c.428-2A>C, c.561_575del:p.A188_E192del, c.836G>A:p.C279Y, c.1010_1021del:p.H337_E340del:p.Y479*, c.1516_1517del:p.S506Pfs*66, c.1561T>G:p.C521G, c.1616G>A:p.R539H, and c.1735C>T:p.P579S) and six previously reported variants in MFRP, with p.E496K and p.H337_E340del being highly frequent, found in eight (47.06 %) and two families (11.76 %), respectively. Seven variants (43.75 %) were located in the C-terminal cysteine-rich frizzled-related domain (CRD) (7/16, 43.75 %). Protein prediction implicated p.E496K and p.H337_E340del mutations might lead to a destabilization of the MFRP protein. The average AL of all 42 eyes was 16.02 ± 1.05 mm, and 78.36 % of eyes with AL < 16 mm harbored p.E496K variant. Twenty-six eyes with variant variant had shorter AL than that of the other 16 eyes without this variant (p = 0.006), highlighting a novel genotype-phenotype correlation. CONCLUSIONS In this largest cohort of Chinese patients with microphthalmia, the 9 novel variants, high frequency of p.E496W, and mutation hotspots in CRD reveals unique insights into the MFRP mutation spectrum among Chinese patients, indicating ethnic variability. A new genotype-phenotype correlation that p.E496K variant associated with a shorter AL is unveiled. Our findings enhance the current knowledge of MFRP-associated microphthalmia and provide valuable information for prenatal diagnosis as well as future therapy.
Collapse
Affiliation(s)
- Jing Tao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing 100730, China
| | - Jingyi Luo
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510000, China
| | - Kaijing Li
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510000, China
| | - Runcai Yang
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510000, China
| | - Yixiu Lin
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510000, China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong 510000, China.
| |
Collapse
|
2
|
Li Z, Ma R, Ma M, Xiao X, Qi X, Ma H, Sheng X, Rong W. MFRP variations cause nanophthalmos in five Chinese families with distinct phenotypic diversity. Front Genet 2024; 15:1407361. [PMID: 39076172 PMCID: PMC11284154 DOI: 10.3389/fgene.2024.1407361] [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: 03/26/2024] [Accepted: 06/21/2024] [Indexed: 07/31/2024] Open
Abstract
Purpose Nanophthalmos is a congenital ocular structural anomaly that can cause significant visual loss in children. The early diagnosis and then taking appropriate clinical and surgical treatment remains a challenge for many ophthalmologists because of genetic and phenotypic heterogeneity. The objective of this study is to identify the genetic cause of nanophthalmos in the affected families and analyze the clinical phenotype of nanophthalmos with MFRP gene variation (Microphthalmia, isolated; OMIM#611040 and Nanophthalmos 2; OMIM#609549, respectively). Methods Comprehensive ophthalmic examinations were performed on participants to confirm the phenotype. The genotype was identified using whole exome sequencing, and further verified the results among other family members by Sanger sequencing. The normal protein structure was constructed using Alphafold. Mutant proteins were visualized using pymol software. Pathogenicity of identified variant was determined by in silico analysis and the guidelines of American College of Medical Genetics and Genomics (ACMG). The relationship between genetic variants and clinical features was analyzed. Results Five nanophthalmos families were autosomal recessive, of which four families carried homozygous variants and one family had compound heterozygous variants in the MFRP gene. Both family one and family three carried the homozygous missense variant c.1486G>A (p.Glu496Lys) in the MFRP gene (Clinvar:SCV005060845), which is a novel variant and evaluated as likely pathogenic according to the ACMG guidelines and in silico analysis. The proband of family one presented papilloedema in both eyes, irregular borders, thickened retinas at the posterior pole, tortuous and dilated retinal vessels, and indistinguishable arteries and veins, while the proband of family three presented uveal effusion syndrome-like changes in the right eye. In families one and 3, despite carrying the same gene variant, the probands had completely different clinical phenotypes. The homozygous nonsense variant c.271C>T (p.Gln91Ter) (Clinvar:SCV005060846) of the MFRP gene was detected in family 2, presenting shallow anterior chamber in both eyes, pigmentation of peripheral retina 360° from the equator to the serrated rim showing a clear demarcation from the normal retina in the form of strips. Family four proband carried the homozygous missense variant c.1411G>A (p.Val471Met) in the MFRP gene (Clinvar:SCV005060847), family five proband carried compound heterozygous missense variants c.1486G>A (p.Glu496Lys) and c.602G>T (p.Arg201Leu) in the MFRP gene (Clinvar:SCV005060848), which is a novel variant and evaluated as likely pathogenic according to the ACMG guidelines and in silico analysis, and they all presented clinically with binocular angle-closure glaucoma, family four also had retinal vein occlusion in the right eye during the follow-up. Conclusion In this study, pathogenic variants of the MFRP gene were detected in five nanophthalmos families, including two novel variants. It also revealed a distinct phenotypic diversity among five probands harboring variants in the MFRP gene. Our findings extend the phenotype associated with MFRP variants and is helpful for ophthalmologists in early diagnosis and making effective treatment and rehabilitation strategies.
Collapse
Affiliation(s)
- Zhen Li
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| | - Runqing Ma
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| | - Meijiao Ma
- Gansu Aier Optometry Hospital, Lanzhou City, China
| | - Xue Xiao
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| | - Xiaolong Qi
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| | - Hongjuan Ma
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| | - Xunlun Sheng
- Gansu Aier Optometry Hospital, Lanzhou City, China
| | - Weining Rong
- Ningxia Eye Hospital, People’s Hospital of Ningxia Hui Autonomous Region, Ningxia Medical University, Yinchuan, China
| |
Collapse
|
3
|
Amaral RAS, Zin OA, Moraes RT, Porto FBO, Carricondo PC, Pimentel SLG, Kestelman BP, Watanabe SES, Sallum JMF. Posterior microphthalmos with retinal involvement related to MFRP gene: a report of 10 Brazilian patients. Ophthalmic Genet 2024:1-8. [PMID: 38557281 DOI: 10.1080/13816810.2024.2322650] [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: 09/20/2022] [Accepted: 06/01/2023] [Indexed: 04/04/2024]
Abstract
BACKGROUND To describe the phenotype and genotype of 10 Brazilian patients with variants in MFRP, posterior microphthalmos and retinal findings. METHODS Complete ophthalmological evaluation was done at 4 different Brazilian centers. Genetic analysis was performed using commercial next generation sequencing panels for inherited retinal disorders. RESULTS Ages of the patients ranged from 10 to 65 years and visual acuities from 0,05 to no perception of light. All were hyperopes (+4,25 to + 17,50) with a short axial length (14,4 mm to 18 mm). Common posterior segment features, though not present in all, were optic disc drusen (5/10), foveoschisis (5/10) and retinal pigmentary changes (8/10). Isolated patients presented with macular atrophy, serous retinal detachment, and chorioretinal folds. The most common variant in MFRP found in our patients was a deletion in exon 5 (c.498delC; p.Asn267Thrfs *25), present in all except 2 patients. Other variants found were c.523C>T (p.Gln175*), c.298delG (p.Ala100Argfs *37), c.666del (p.Thr223Argfs *83) and the novel variant c.257C>A (p.Ala86Asp). CONCLUSIONS This is the first report of Brazilian patients with posterior microphthalmos and pathogenic variants in MFRP and the first describe of the variant p.Ala86Asp in literature. Our cases confirm the previously reported phenotype of high hyperopia, optic disc drusen, alterations in foveal architecture, retinal pigmentary changes with loss of photoreceptor function and visual field constriction. Report of such a rare condition is important to increase awareness to the phenotype of posterior microphthalmia with associated retinal conditions.
Collapse
Affiliation(s)
- Rebeca A S Amaral
- Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
- Instituto de Genética Ocular (IGO), São Paulo, Brazil
| | - Olivia A Zin
- Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
- Brazilian Institute of Ophthalmology (IBOL), Rio de Janeiro, Brazil
| | - Remo T Moraes
- Brazilian Institute of Ophthalmology (IBOL), Rio de Janeiro, Brazil
| | - Fernanda B O Porto
- INRET Clínica e Centro de Pesquisa, Brazil
- Centro Oftalmológico de Minas Gerais, Brazil
- Clínica de Olhos da Santa Casa de Belo Horizonte, Brazil
| | | | | | | | - Sung E S Watanabe
- Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
| | - Juliana M F Sallum
- Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
- Instituto de Genética Ocular (IGO), São Paulo, Brazil
| |
Collapse
|
4
|
Fernández-Vigo JI, Gómez-de-Liaño CN, Rodríguez-Quet O, Burgos-Blasco B, Montolío-Marzo E, de-Pablo-Gómez-de-Liaño L, González-Martin-Moro J, García-Feijóo J. Clinical update in nanophthalmos: Features, diseases and complications associated. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2023; 98:687-702. [PMID: 37813187 DOI: 10.1016/j.oftale.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/25/2023] [Indexed: 10/11/2023]
Abstract
Nanophthalmos is a rare congenital condition of the eyeball that is characterised by a smaller size of the anterior and posterior segments without associated ocular malformations. Typical features that have traditionally been described in these eyes are short axial length, thickened sclera, cornea with a smaller diameter, narrow anterior chamber, and an increased lens to globe volume ratio. However, at present, there is still a lack of recognised diagnostic criteria for nanophthalmos and a classification of its severity. Its clinical relevance stems from the increased risk of multiple ocular conditions, such as high hyperopia, amblyopia, angle-closure glaucoma, retinal detachment, and cataracts. Likewise, in relation to surgery in these eyes, there are particularities in cataract and glaucoma surgery and with a greater risk of associated intra- and postoperative complications. In this way, the treatment of nanophthalmos focuses on controlling the associated eye conditions and reducing and controlling surgical complications. This review aims to update what has been published in recent years regarding nanophthalmos.
Collapse
Affiliation(s)
- J I Fernández-Vigo
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain; Centro Internacional de Oftalmología Avanzada, Madrid, Spain.
| | - C N Gómez-de-Liaño
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | - O Rodríguez-Quet
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | - B Burgos-Blasco
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | - E Montolío-Marzo
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| | | | - J González-Martin-Moro
- Departamento de Oftalmología, Hospital Universitario del Henares, Coslada, Madrid, Spain
| | - J García-Feijóo
- Departamento de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Madrid, Spain
| |
Collapse
|
5
|
Ota J, Inooka T, Okado S, Maeda N, Koyanagi Y, Kominami T, Nishiguchi KM, Ueno S. Pathogenic variants of MFRP and PRSS56 genes are major causes of nanophthalmos in Japanese patients. Ophthalmic Genet 2023; 44:423-429. [PMID: 37501562 DOI: 10.1080/13816810.2023.2208220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/23/2023] [Accepted: 04/24/2023] [Indexed: 07/29/2023]
Abstract
BACKGROUND Nanophthalmos (NNO) is a rare condition with significantly shorter axial length than normal. Several genes are known to cause NNO, among them the MFRP and PRSS56 genes have been reported to cause majority of NNOs. The purpose of this study was to determine the genetic basis of Japanese patients with NNO. MATERIALS AND METHODS We studied seven patients with NNO. Whole exome sequencing (WES) and Sanger sequencing were performed to determine the variants causing the NNO. We also reviewed the medical charts of the patients to determine the phenotype of these seven patients. RESULTS WES revealed that four patients from three families carried homozygous frameshift variants of the PRSS56 gene (c.1066dupC). Two novel variants of the MFRP gene were detected in the other two patients: one proband had a homozygous missense variant (c.1486 G>A) and the other had a compound heterozygous variant (c.1486 G>A and c.662_663insT). The axial length of the eight eyes with the PRSS56 variant was 15.69 ± 0.48 mm (mean ± SD) and that for the 4 eyes with the MFRP variant was 15.63 ± 0.69 mm. Three of the six cases with the PRSS56 or MFRP variant had the uveal effusion syndrome. CONCLUSIONS NNOs in Japanese patients are caused by variants of the PRSS56 and MFRP genes as in other ethnic populations. In addition, two new variants of the MFRP gene were found in our cohort. The phenotypes and anomalies in Japanese patients with NNO were similar to those reported for other ethnic populations.
Collapse
Affiliation(s)
- Junya Ota
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Taiga Inooka
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Satoshi Okado
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Natsuki Maeda
- Department of Ophthalmology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Yoshito Koyanagi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Taro Kominami
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Koji M Nishiguchi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Department of Ophthalmology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| |
Collapse
|
6
|
Jackson D, Moosajee M. The Genetic Determinants of Axial Length: From Microphthalmia to High Myopia in Childhood. Annu Rev Genomics Hum Genet 2023; 24:177-202. [PMID: 37624667 DOI: 10.1146/annurev-genom-102722-090617] [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] [Indexed: 08/27/2023]
Abstract
The axial length of the eye is critical for normal visual function by enabling light to precisely focus on the retina. The mean axial length of the adult human eye is 23.5 mm, but the molecular mechanisms regulating ocular axial length remain poorly understood. Underdevelopment can lead to microphthalmia (defined as a small eye with an axial length of less than 19 mm at 1 year of age or less than 21 mm in adulthood) within the first trimester of pregnancy. However, continued overgrowth can lead to axial high myopia (an enlarged eye with an axial length of 26.5 mm or more) at any age. Both conditions show high genetic and phenotypic heterogeneity associated with significant visual morbidity worldwide. More than 90 genes can contribute to microphthalmia, and several hundred genes are associated with myopia, yet diagnostic yields are low. Crucially, the genetic pathways underpinning the specification of eye size are only now being discovered, with evidence suggesting that shared molecular pathways regulate under- or overgrowth of the eye. Improving our mechanistic understanding of axial length determination will help better inform us of genotype-phenotype correlations in both microphthalmia and myopia, dissect gene-environment interactions in myopia, and develop postnatal therapies that may influence overall eye growth.
Collapse
Affiliation(s)
- Daniel Jackson
- Institute of Ophthalmology, University College London, London, United Kingdom;
| | - Mariya Moosajee
- Institute of Ophthalmology, University College London, London, United Kingdom;
- The Francis Crick Institute, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| |
Collapse
|
7
|
Tian X, Zheng Q, Xie J, Zhou Q, Liang L, Xu G, Chen H, Ling C, Lu D. Improved gene therapy for MFRP deficiency-mediated retinal degeneration by knocking down endogenous bicistronic Mfrp and Ctrp5 transcript. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 32:843-856. [PMID: 37273779 PMCID: PMC10238587 DOI: 10.1016/j.omtn.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 05/04/2023] [Indexed: 06/06/2023]
Abstract
The membrane frizzled-related protein (Mfrp) and C1-tumor necrosis factor related protein 5 (Ctrp5) genes are transcribed as a bicistronic unit and dysregulation of either gene is associated with retinal degeneration in the retinal pigment epithelium (RPE) cells. However, the mechanisms that regulate the expression of the bicistronic transcript remain controversial. Here, we identified a microRNA-based negative feedback loop that helps maintain a normal expression level of the bicistronic Mfrp and Ctrp5 transcript. Specifically, miR-149-3p, a conserved microRNA, binds to the 3'UTR of the Mfrp gene. In MFRP-deficient rd6 mice, the miR-149-3p levels were compromised compared with those in WT mice, resulting in an increase in the bicistronic transcript. We also report a capsid-modified rAAVDJ-3M vector that is capable of robustly and specifically transducing RPE cells following subretinal delivery. Compared with the parental vector, the modified vector elicited similar levels of serum anti-rAAV antibodies, but recruited fewer microglial infiltrations. Most significantly, we also demonstrate that simultaneous overexpressing of MFRP and knockdown of the bicistronic transcript was more effective in rescuing vision than MFRP overexpression alone. Our findings offer new insights into the function of MFRP and provide a promising therapeutic strategy for the treatment of MFRP-associated ocular diseases.
Collapse
Affiliation(s)
- Xiao Tian
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Qingyun Zheng
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Jinyan Xie
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Qinlinglan Zhou
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Letong Liang
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Guotong Xu
- Department of Ophthalmology of Tongji Hospital and Laboratory of Clinical and Visual Sciences of Tongji Eye Institute, Tongji University School of Medicine, Shanghai 200092, China
| | - Hongyan Chen
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
| | - Chen Ling
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Daru Lu
- State Key Laboratory of Genetic Engineering and Engineering Research Center of Gene Technology (Ministry of Education), School of Life Sciences, Fudan University, Shanghai 200438, China
- NHC Key Laboratory of Birth Defects and Reproductive Health, Chongqing Key Laboratory of Birth Defects and Reproductive Health, Chongqing Population and Family Planning, Science and Technology Research Institute, Chongqing 404100, China
| |
Collapse
|
8
|
Swinkels D, Baes M. The essential role of docosahexaenoic acid and its derivatives for retinal integrity. Pharmacol Ther 2023; 247:108440. [PMID: 37201739 DOI: 10.1016/j.pharmthera.2023.108440] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/08/2023] [Accepted: 05/15/2023] [Indexed: 05/20/2023]
Abstract
The fatty acid composition of photoreceptor outer segment (POS) phospholipids diverges from other membranes, being highly enriched in polyunsaturated fatty acids (PUFAs). The most abundant PUFA is docosahexaenoic acid (DHA, C22:6n-3), an omega-3 PUFA that amounts to over 50% of the POS phospholipid fatty acid side chains. Interestingly, DHA is the precursor of other bioactive lipids such as elongated PUFAs and oxygenated derivatives. In this review, we present the current view on metabolism, trafficking and function of DHA and very long chain polyunsaturated fatty acids (VLC-PUFAs) in the retina. New insights on pathological features generated from PUFA deficient mouse models with enzyme or transporter defects and corresponding patients are discussed. Not only the neural retina, but also abnormalities in the retinal pigment epithelium are considered. Furthermore, the potential involvement of PUFAs in more common retinal degeneration diseases such as diabetic retinopathy, retinitis pigmentosa and age-related macular degeneration are evaluated. Supplementation treatment strategies and their outcome are summarized.
Collapse
Affiliation(s)
- Daniëlle Swinkels
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Myriam Baes
- Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, 3000 Leuven, Belgium.
| |
Collapse
|
9
|
Drinking hydrogen water improves photoreceptor structure and function in retinal degeneration 6 mice. Sci Rep 2022; 12:13610. [PMID: 35948585 PMCID: PMC9365798 DOI: 10.1038/s41598-022-17903-8] [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: 04/15/2022] [Accepted: 08/02/2022] [Indexed: 11/08/2022] Open
Abstract
Retinitis pigmentosa (RP) is a genetically heterogeneous group of inherited retinal disorders involving the progressive dysfunction of photoreceptors and the retinal pigment epithelium, for which there is currently no treatment. The rd6 mouse is a natural model of autosomal recessive retinal degeneration. Given the known contributions of oxidative stress caused by reactive oxygen species (ROS) and selective inhibition of potent ROS peroxynitrite and OH·by H2 gas we have previously demonstrated, we hypothesized that ingestion of H2 water may delay the progression of photoreceptor death in rd6 mice. H2 mice showed significantly higher retinal thickness as compared to controls on optical coherence tomography. Histopathological and morphometric analyses revealed higher thickness of the outer nuclear layer for H2 mice than controls, as well as higher counts of opsin red/green-positive cells. RNA sequencing (RNA-seq) analysis of differentially expressed genes in the H2 group versus control group revealed 1996 genes with significantly different expressions. Gene and pathway ontology analysis showed substantial upregulation of genes responsible for phototransduction in H2 mice. Our results show that drinking water high in H2 (1.2-1.6 ppm) had neuroprotective effects and inhibited photoreceptor death in mice, and suggest the potential of H2 for the treatment of RP.
Collapse
|
10
|
Non-vasogenic cystoid maculopathies. Prog Retin Eye Res 2022; 91:101092. [PMID: 35927124 DOI: 10.1016/j.preteyeres.2022.101092] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 05/30/2022] [Accepted: 06/01/2022] [Indexed: 11/23/2022]
Abstract
Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM) may be detected on optical coherence tomography but not on fluorescein angiography. Various causes may disrupt retinal cell cohesion or impair retinal pigment epithelium (RPE) and Müller cell functions in the maintenance of retinal dehydration, resulting in cystoid spaces formation. Tractional causes include vitreomacular traction, epiretinal membranes and myopic foveoschisis. Surgical treatment does not always allow cystoid space resorption. In inherited retinal dystrophies, cystoid spaces may be part of the disease as in X-linked retinoschisis or enhanced S-cone syndrome, or occur occasionally as in bestrophinopathies, retinitis pigmentosa and allied diseases, congenital microphthalmia, choroideremia, gyrate atrophy and Bietti crystalline dystrophy. In macular telangiectasia type 2, cystoid spaces and cavitations do not depend on the fluid leakage from telangiectasia. Various causes affecting RPE function may result in NVCM such as chronic central serous chorioretinopathy and paraneoplastic syndromes. Non-exudative age macular degeneration may also be complicated by intraretinal cystoid spaces in the absence of fluorescein leakage. In these diseases, cystoid spaces occur in a context of retinal cell loss. Various causes of optic atrophy, including open-angle glaucoma, result in microcystoid spaces in the inner nuclear layer due to a retrograde transsynaptic degeneration. Lastly, drug toxicity may also induce cystoid maculopathy. Identifying NVCM on multimodal imaging, including fluorescein angiography if needed, allows guiding the diagnosis of the causative disease and choosing adequate treatment when available.
Collapse
|
11
|
Lopez-Cañizares A, Carletti P, Berrocal AM. A Young Boy With Changes in the Retinal Pigment Epithelium. JAMA Ophthalmol 2022; 140:1015-1016. [PMID: 35862055 DOI: 10.1001/jamaophthalmol.2022.1653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
12
|
Ren X, Gao Y, Lin Y, Fu X, Xiao L, Wang X, Zeng Z, Bao L, Yan N, Zhang M, Tang L. A Novel Mutation in the Membrane Frizzled-Related Protein Gene for Posterior Microphthalmia, Non-pigmented Retinitis Pigmentosa, Optic Nerve Drusen, and Retinoschisis in a Consanguineous Family. Front Med (Lausanne) 2022; 9:835621. [PMID: 35402469 PMCID: PMC8987310 DOI: 10.3389/fmed.2022.835621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background Microphthalmos (MCO) is a rare developmental defect characterized by small malformed eyes. Our study aimed to describe the clinical characteristics of posterior microphthalmos syndrome caused by a novel variant in MFRP gene in a Chinese patient. Methods Complete ophthalmologic examinations were performed for the proband and proband's family members. Whole exon sequencing (WES) and Sanger sequencing were used to identify the mutated genes, and bioinformatic analysis was undertaken to predict the effect of this variant. Results Clinical analysis showed that the proband had reduced axial length (17.95 and 17.98 mm) with normal-size corneas and shallow anterior chamber depth. Fundus photography showed scattered yellowish-white spots in the whole retina with cup-to-disc ratios of 0.95 in both eyes. Retinoschisis in the inner nuclear layer and reduced outer retina thickness were apparent on OCT examination, and optic nerve drusen demonstrated increased autofluorescence in fundus autofluorescence (FAF). Perimeter examination revealed a tubular visual field for the right eye, and electroretinography (ERG) revealed a moderately reduced rod response combined with compromised cone response. Ocular examinations of the patient's family members were unremarkable. WES revealed that the proband had homozygous mutations in c.55-1 (IVS1) G>A in intron 1 for the MFRP gene. Both the proband's parents and offspring were confirmed to be heterozygous by Sanger sequencing. Bioinformatic analysis showed this mutation was deleterious. Conclusion We reported autosomal recessive posterior microphthalmia, atypical retinitis pigmentosa, and retinoschisis caused by a novel mutation in the MFRP gene in this consanguineous marriage family. Our study further broadens the mutation and phenotype spectrum of the MFRP gene in microphthalmia.
Collapse
Affiliation(s)
- Xiang Ren
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yunxia Gao
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yu Lin
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiangyu Fu
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Lirong Xiao
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiaoyue Wang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Zhibing Zeng
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Li Bao
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Naihong Yan
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Ming Zhang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Ming Zhang
| | - Li Tang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Li Tang
| |
Collapse
|
13
|
Quint WH, Tadema KCD, Crins JHC, Kokke NCCJ, Meester-Smoor MA, Willemsen R, Klaver CCW, Iglesias AI. Zebrafish: An In Vivo Screening Model to Study Ocular Phenotypes. Transl Vis Sci Technol 2022; 11:17. [PMID: 35285860 PMCID: PMC8934544 DOI: 10.1167/tvst.11.3.17] [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] [Indexed: 11/24/2022] Open
Abstract
Purpose To establish a set of assays that allow the in vivo screening of candidate genes for ocular diseases in zebrafish, with an emphasis on refractive error. Methods Our pipeline includes the most relevant ocular screening measurements to assess (1) ocular biometry using spectral domain optical coherence tomography, (2) refractive status using an eccentric photorefractor, (3) intraocular pressure by tonometry, and (4) optokinetic response to study visual capability in zebrafish. To validate our pipeline and to demonstrate the potential of zebrafish as a valid animal model, we chose two well-characterized genes with an ocular phenotype (PRSS56 and FBN1) and generated two mutant zebrafish lines (prss56 and fbn1). Mutant fish were assessed at 2, 4, and 6 months after fertilization. Results With the proposed phenotyping pipeline, we showed that ocular biometry, refractive status, intraocular pressure, and visual function can be studied in zebrafish. In the prss56 mutant, the pipeline revealed a dramatic decrease in axial length, mainly owing to a decreased vitreous chamber depth, whereas in the fbn1 mutant, ectopia lentis was the most distinctive ocular phenotype observed. Tonometry in both mutant lines showed an increase in intraocular pressure. Conclusions The proposed pipeline was applied successfully in zebrafish and can be used for future genetic screenings of candidate genes. While validating our pipeline, we found a close resemblance between the ocular manifestations in the zebrafish mutants and patients harboring mutations in PRSS56 and FBN1. Our results support the validity of our pipeline and highlight the potential of zebrafish as an animal model for in vivo screening of candidate genes for ocular diseases.
Collapse
Affiliation(s)
- Wim H Quint
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Kirke C D Tadema
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Johan H C Crins
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Nina C C J Kokke
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Magda A Meester-Smoor
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Rob Willemsen
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Caroline C W Klaver
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Epidemiology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Ophthalmology, Radboud University Medical Center, Nijmegen, the Netherlands.,Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland
| | - Adriana I Iglesias
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, the Netherlands.,Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| |
Collapse
|
14
|
Genetic Interaction between Mfrp and Adipor1 Mutations Affect Retinal Disease Phenotypes. Int J Mol Sci 2022; 23:ijms23031615. [PMID: 35163536 PMCID: PMC8835889 DOI: 10.3390/ijms23031615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 12/12/2022] Open
Abstract
Adipor1tm1Dgen and Mfrprd6 mutant mice share similar eye disease characteristics. Previously, studies established a functional relationship of ADIPOR1 and MFRP proteins in maintaining retinal lipidome homeostasis and visual function. However, the independent and/or interactive contribution of both genes to similar disease phenotypes, including fundus spots, decreased axial length, and photoreceptor degeneration has yet to be examined. We performed a gene-interaction study where homozygous Adipor1tm1Dgen and Mfrprd6 mice were bred together and the resulting doubly heterozygous F1 offspring were intercrossed to produce 210 F2 progeny. Four-month-old mice from all nine genotypic combinations obtained in the F2 generation were assessed for white spots by fundus photo documentation, for axial length by caliper measurements, and for photoreceptor degeneration by histology. Two-way factorial ANOVA was performed to study individual as well as gene interaction effects on each phenotype. Here, we report the first observation of reduced axial length in Adipor1tmlDgen homozygotes. We show that while Adipor1 and Mfrp interact to affect spotting and degeneration, they act independently to control axial length, highlighting the complex functional association between these two genes. Further examination of the molecular basis of this interaction may help in uncovering mechanisms by which these genes perturb ocular homeostasis.
Collapse
|
15
|
Brandt ZJ, Collery RF, Besharse JC, Link BA. Ablation of mpeg+ Macrophages Exacerbates mfrp-Related Hyperopia. Invest Ophthalmol Vis Sci 2021; 62:13. [PMID: 34913948 PMCID: PMC8684298 DOI: 10.1167/iovs.62.15.13] [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] [Indexed: 11/24/2022] Open
Abstract
Purpose Proper refractive development of the eye, termed emmetropization, is critical for focused vision and is impacted by both genetic determinants and several visual environment factors. Improper emmetropization caused by genetic variants can lead to congenital hyperopia, which is characterized by small eyes and relatively short ocular axial length. To date, variants in only four genes have been firmly associated with human hyperopia, one of which is MFRP. Zebrafish mfrp mutants also have hyperopia and, similar to reports in mice, exhibit increased macrophage recruitment to the retina. The goal of this research was to examine the effects of macrophage ablation on emmetropization and mfrp-related hyperopia. Methods We utilized a chemically inducible, cell-specific ablation system to deplete macrophages in both wild-type and mfrp mutant zebrafish. Spectral-domain optical coherence tomography was then used to measure components of the eye and determine relative refractive state. Histology, immunohistochemistry, and transmission electron microscopy were used to further study the eyes. Results Although macrophage ablation does not cause significant changes to the relative refractive state of wild-type zebrafish, macrophage ablation in mfrp mutants significantly exacerbates their hyperopic phenotype, resulting in a relative refractive error 1.3 times higher than that of non-ablated mfrp siblings. Conclusions Genetic inactivation of mfrp leads to hyperopia, as well as abnormal accumulation of macrophages in the retina. Ablation of the mpeg1-positive macrophage population exacerbates the hyperopia, suggesting that macrophages may be recruited in an effort help preserve emmetropization and ameliorate hyperopia.
Collapse
Affiliation(s)
- Zachary J Brandt
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Ross F Collery
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Joseph C Besharse
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Brian A Link
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| |
Collapse
|
16
|
Balikov DA, Jacobson A, Prasov L. Glaucoma Syndromes: Insights into Glaucoma Genetics and Pathogenesis from Monogenic Syndromic Disorders. Genes (Basel) 2021; 12:genes12091403. [PMID: 34573386 PMCID: PMC8471311 DOI: 10.3390/genes12091403] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/02/2021] [Accepted: 09/08/2021] [Indexed: 11/21/2022] Open
Abstract
Monogenic syndromic disorders frequently feature ocular manifestations, one of which is glaucoma. In many cases, glaucoma in children may go undetected, especially in those that have other severe systemic conditions that affect other parts of the eye and the body. Similarly, glaucoma may be the first presenting sign of a systemic syndrome. Awareness of syndromes associated with glaucoma is thus critical both for medical geneticists and ophthalmologists. In this review, we highlight six categories of disorders that feature glaucoma and other ocular or systemic manifestations: anterior segment dysgenesis syndromes, aniridia, metabolic disorders, collagen/vascular disorders, immunogenetic disorders, and nanophthalmos. The genetics, ocular and systemic features, and current and future treatment strategies are discussed. Findings from rare diseases also uncover important genes and pathways that may be involved in more common forms of glaucoma, and potential novel therapeutic strategies to target these pathways.
Collapse
Affiliation(s)
- Daniel A. Balikov
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA; (D.A.B.); (A.J.)
| | - Adam Jacobson
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA; (D.A.B.); (A.J.)
| | - Lev Prasov
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA; (D.A.B.); (A.J.)
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
- Correspondence:
| |
Collapse
|
17
|
Retinal Stem Cell 'Retirement Plans': Growth, Regulation and Species Adaptations in the Retinal Ciliary Marginal Zone. Int J Mol Sci 2021; 22:ijms22126528. [PMID: 34207050 PMCID: PMC8234741 DOI: 10.3390/ijms22126528] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
The vertebrate retina develops from a specified group of precursor cells that adopt distinct identities and generate lineages of either the neural retina, retinal pigmented epithelium, or ciliary body. In some species, including teleost fish and amphibians, proliferative cells with stem-cell-like properties capable of continuously supplying new retinal cells post-embryonically have been characterized and extensively studied. This region, termed the ciliary or circumferential marginal zone (CMZ), possibly represents a conserved retinal stem cell niche. In this review, we highlight the research characterizing similar CMZ-like regions, or stem-like cells located at the peripheral margin, across multiple different species. We discuss the proliferative parameters, multipotency and growth mechanisms of these cells to understand how they behave in vivo and how different molecular factors and signalling networks converge at the CMZ niche to regulate their activity. The evidence suggests that the mature retina may have a conserved propensity for homeostatic growth and plasticity and that dysfunction in the regulation of CMZ activity may partially account for dystrophic eye growth diseases such as myopia and hyperopia. A better understanding of the properties of CMZ cells will enable important insight into how an endogenous generative tissue compartment can adapt to altered retinal physiology and potentially even restore vision loss caused by retinal degenerative conditions.
Collapse
|
18
|
Lang E, Koller S, Atac D, Pfäffli OA, Hanson JV, Feil S, Bähr L, Bahr A, Kottke R, Joset P, Fasler K, Barthelmes D, Steindl K, Konrad D, Wille D, Berger W, Gerth‐Kahlert C. Genotype-phenotype spectrum in isolated and syndromic nanophthalmos. Acta Ophthalmol 2021; 99:e594-e607. [PMID: 32996714 DOI: 10.1111/aos.14615] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 08/01/2020] [Indexed: 12/11/2022]
Abstract
PURPOSE To (i) describe a series of patients with isolated or syndromic nanophthalmos with the underlying genetic causes, including novel pathogenic variants and their functional characterization and (ii) to study the association of retinal dystrophy in patients with MFRP variants, based on a detailed literature review of genotype-phenotype correlations. METHODS Patients with nanophthalmos and available family members received a comprehensive ophthalmological examination. Genetic analysis was based on whole-exome sequencing and variant calling in core genes including MFRP, BEST1, TMEM98, PRSS56, CRB1, GJA1, C1QTNF5, MYRF and FAM111A. A minigene assay was performed for functional characterization of a splice site variant. RESULTS Seven patients, aged between three and 65 years, from five unrelated families were included. Novel pathogenic variants in MFRP (c.497C>T, c.899-3C>A, c.1180G>A), and PRSS56 (c.1202C>A), and a recurrent de novo variant in FAM111A (c.1706G>A) in a patient with Kenny-Caffey syndrome type 2, were identified. In addition, we report co-inheritance of MFRP-related nanophthalmos and ADAR-related Aicardi-Goutières syndrome. CONCLUSION Nanophthalmos is a genetically heterogeneous condition, and the severity of ocular manifestations appears not to correlate with variants in a specific gene. However, retinal dystrophy is only observed in patients harbouring pathogenic MFRP variants. Furthermore, heterozygous carriers of MFRP and PRSS56 should be screened for the presence of high hyperopia. Identifying nanophthalmos as an isolated condition or as part of a syndrome has implications for counselling and can accelerate the interdisciplinary care of patients.
Collapse
Affiliation(s)
- Elena Lang
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
| | - Samuel Koller
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
| | - David Atac
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
| | - Oliver A. Pfäffli
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
| | - James V.M. Hanson
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
| | - Silke Feil
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
| | - Luzy Bähr
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
| | - Angela Bahr
- Institute of Medical Genetics University of Zurich Zurich Switzerland
| | - Raimund Kottke
- Department of Diagnostic Imaging University Children's Hospital Zurich Zurich Switzerland
| | - Pascal Joset
- Institute of Medical Genetics University of Zurich Zurich Switzerland
| | - Katrin Fasler
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
| | - Daniel Barthelmes
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
- Save Sight Institute The University of Sydney Sydney NSW Australia
| | - Katharina Steindl
- Institute of Medical Genetics University of Zurich Zurich Switzerland
| | - Daniel Konrad
- Department of Pediatric Endocrinology and Diabetology University Children’s Hospital Zurich Switzerland
| | | | - Wolfgang Berger
- Institute of Medical Molecular Genetics University of Zurich Schlieren Switzerland
- Zurich Center for Integrative Human Physiology University of Zurich Zurich Switzerland
- Neuroscience Center Zurich, University and ETH Zurich Zurich Switzerland
| | - Christina Gerth‐Kahlert
- Department of Ophthalmology University Hospital Zurich and University of Zurich Zurich Switzerland
| |
Collapse
|
19
|
Koli S, Labelle-Dumais C, Zhao Y, Paylakhi S, Nair KS. Identification of MFRP and the secreted serine proteases PRSS56 and ADAMTS19 as part of a molecular network involved in ocular growth regulation. PLoS Genet 2021; 17:e1009458. [PMID: 33755662 PMCID: PMC8018652 DOI: 10.1371/journal.pgen.1009458] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 04/02/2021] [Accepted: 03/01/2021] [Indexed: 12/24/2022] Open
Abstract
Precise regulation of ocular size is a critical determinant of normal visual acuity. Although it is generally accepted that ocular growth relies on a cascade of signaling events transmitted from the retina to the sclera, the factors and mechanism(s) involved are poorly understood. Recent studies have highlighted the importance of the retinal secreted serine protease PRSS56 and transmembrane glycoprotein MFRP, a factor predominantly expressed in the retinal pigment epithelium (RPE), in ocular size determination. Mutations in PRSS56 and MFRP constitute a major cause of nanophthalmos, a condition characterized by severe reduction in ocular axial length/extreme hyperopia. Interestingly, common variants of these genes have been implicated in myopia, a condition associated with ocular elongation. Consistent with these findings, mice with loss of function mutation in PRSS56 or MFRP exhibit a reduction in ocular axial length. However, the molecular network and cellular processes involved in PRSS56- and MFRP-mediated ocular axial growth remain elusive. Here, we show that Adamts19 expression is significantly upregulated in the retina of mice lacking either Prss56 or Mfrp. Importantly, using genetic mouse models, we demonstrate that while ADAMTS19 is not required for ocular growth during normal development, its inactivation exacerbates ocular axial length reduction in Prss56 and Mfrp mutant mice. These results suggest that the upregulation of retinal Adamts19 is part of an adaptive molecular response to counteract impaired ocular growth. Using a complementary genetic approach, we show that loss of PRSS56 or MFRP function prevents excessive ocular axial growth in a mouse model of early-onset myopia caused by a null mutation in Irbp, thus, demonstrating that PRSS56 and MFRP are also required for pathological ocular elongation. Collectively, our findings provide new insights into the molecular network involved in ocular axial growth and support a role for molecular crosstalk between the retina and RPE involved in refractive development. During ocular refractive development, the eye’s growth is modulated, such that the ocular axial length matches the optical power enabling the eyes to achieve optimal focus. Alterations in ocular growth mainly contribute to refractive errors. Mutations in human PRSS56 and MFRP are responsible for nanophthalmos that exhibit a severe reduction in ocular axial length, and high hyperopia. Importantly, mutant mouse models lacking either Müller glia expressed PRSS56, or retinal pigment epithelium (RPE) localized MFRP exhibit ocular axial length reduction. Here, we have identified Adamts19 as a factor whose levels were significantly upregulated in the retina of mice lacking either Prss56 or Mfrp. Importantly, utilizing Adamts19 knockout mice we demonstrate that upregulation of retinal Adamts19 expression constitutes a compensatory mechanism that provides partial protection against ocular axial reduction due to mutation in Prss56 and Mfrp. Next, utilizing a mouse model of early-onset myopia, we demonstrate that the mutant Irbp induced ocular axial elongation is completely dependent on Prss56 as well as Mfrp, suggesting an interplay between Müller glia and RPE in the regulation of ocular axial growth. Collectively, these findings suggest that ocular refractive development relies on complex interactions occurring between genetic factors in the retina and RPE.
Collapse
Affiliation(s)
- Swanand Koli
- Department of Ophthalmology, University of California, San Francisco, California, United States of America
| | - Cassandre Labelle-Dumais
- Department of Ophthalmology, University of California, San Francisco, California, United States of America
| | - Yin Zhao
- Department of Ophthalmology, University of California, San Francisco, California, United States of America
| | - Seyyedhassan Paylakhi
- Department of Ophthalmology, University of California, San Francisco, California, United States of America
| | - K. Saidas Nair
- Department of Ophthalmology, University of California, San Francisco, California, United States of America
- Department of Anatomy, University of California, San Francisco, California, United States of America
- * E-mail:
| |
Collapse
|
20
|
Prasov L, Guan B, Ullah E, Archer SM, Ayres BM, Besirli CG, Wiinikka-Buesser L, Comer GM, Del Monte MA, Elner SG, Garnai SJ, Huryn LA, Johnson K, Kamat SS, Lieu P, Mian SI, Rygiel CA, Serpen JY, Pawar HS, Brooks BP, Moroi SE, Richards JE, Hufnagel RB. Novel TMEM98, MFRP, PRSS56 variants in a large United States high hyperopia and nanophthalmos cohort. Sci Rep 2020; 10:19986. [PMID: 33203948 PMCID: PMC7672112 DOI: 10.1038/s41598-020-76725-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/26/2020] [Indexed: 12/18/2022] Open
Abstract
Nanophthalmos is a rare condition defined by a small, structurally normal eye with resultant high hyperopia. While six genes have been implicated in this hereditary condition (MFRP, PRSS56, MYRF, TMEM98, CRB1,VMD2/BEST1), the relative contribution of these to nanophthalmos or to less severe high hyperopia (≥ + 5.50 spherical equivalent) has not been fully elucidated. We collected probands and families (n = 56) with high hyperopia or nanophthalmos (≤ 21.0 mm axial length). Of 53 families that passed quality control, plausible genetic diagnoses were identified in 10/53 (18.8%) by high-throughput panel or pooled exome sequencing. These include 1 TMEM98 family (1.9%), 5 MFRP families (9.4%), and 4 PRSS56 families (7.5%), with 4 additional families having single allelic hits in MFRP or PRSS56 (7.5%). A novel deleterious TMEM98 variant (NM_015544.3, c.602G>C, p.(Arg201Pro)) segregated with disease in 4 affected members of a family. Multiple novel missense and frameshift variants in MFRP and PRSS56 were identified. PRSS56 families were more likely to have choroidal folds than other solved families, while MFRP families were more likely to have retinal degeneration. Together, this study defines the prevalence of nanophthalmos gene variants in high hyperopia and nanophthalmos and indicates that a large fraction of cases remain outside of single gene coding sequences.
Collapse
Affiliation(s)
- Lev Prasov
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA. .,Department of Human Genetics, University of Michigan, Ann Arbor, MI, 48109, USA.
| | - Bin Guan
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Ehsan Ullah
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Steven M Archer
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Bernadete M Ayres
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Cagri G Besirli
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Laurel Wiinikka-Buesser
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Grant M Comer
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Monte A Del Monte
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Susan G Elner
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Sarah J Garnai
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Laryssa A Huryn
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kayla Johnson
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Shivani S Kamat
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Philip Lieu
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Shahzad I Mian
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Christine A Rygiel
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Jasmine Y Serpen
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA.,Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.,Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Hemant S Pawar
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Brian P Brooks
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sayoko E Moroi
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA.,Department of Ophthalmology and Visual Sciences, The Ohio State University, Columbus, OH, 43212, USA
| | - Julia E Richards
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Robert B Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|
21
|
Sen P, Robson AG, Webster AR, Nicholson L, Sivaprasad S, Hykin PG. Long-term follow-up of a case of posterior microphthalmos (PRSS56) with hyperautofluorescent retinal pigment epithelial deposits. Eur J Ophthalmol 2020; 32:NP163-NP167. [PMID: 32806950 DOI: 10.1177/1120672120949756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To report a case of posterior microphthalomos (PM) related to PRSS56 gene mutation with long term follow up with multimodal imaging findings. METHODS Single retrospective case report. RESULTS A 43-year old male patient presented in 2009 with bilateral reduced vision. Clinical examination and multimodal imaging showed features consistent with posterior microphthalmos with prominent bilateral horizontal papillomacular retinal folds. Posterior pole hyperautofluorescent RPE deposits were present. Gradual worsening of visual acuity and rod and cone photoreceptor function more so on the left was demonstrated during the 8 years of follow up. CONCLUSION Hyperautofluorescent RPE deposits may occur in patients with posterior microphthalmos and such patient's may experience only gradual disease progression over long term follow up.
Collapse
Affiliation(s)
- Piyali Sen
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK.,UCL Institute of Ophthalmology, London, UK
| | - Anthony G Robson
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| | - Andrew R Webster
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK.,UCL Institute of Ophthalmology, London, UK
| | - Luke Nicholson
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| | - Sobha Sivaprasad
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK.,UCL Institute of Ophthalmology, London, UK
| | - Philip G Hykin
- National Institute for Health Research Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| |
Collapse
|
22
|
Collin GB, Gogna N, Chang B, Damkham N, Pinkney J, Hyde LF, Stone L, Naggert JK, Nishina PM, Krebs MP. Mouse Models of Inherited Retinal Degeneration with Photoreceptor Cell Loss. Cells 2020; 9:cells9040931. [PMID: 32290105 PMCID: PMC7227028 DOI: 10.3390/cells9040931] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal degeneration (RD) leads to the impairment or loss of vision in millions of individuals worldwide, most frequently due to the loss of photoreceptor (PR) cells. Animal models, particularly the laboratory mouse, have been used to understand the pathogenic mechanisms that underlie PR cell loss and to explore therapies that may prevent, delay, or reverse RD. Here, we reviewed entries in the Mouse Genome Informatics and PubMed databases to compile a comprehensive list of monogenic mouse models in which PR cell loss is demonstrated. The progression of PR cell loss with postnatal age was documented in mutant alleles of genes grouped by biological function. As anticipated, a wide range in the onset and rate of cell loss was observed among the reported models. The analysis underscored relationships between RD genes and ciliary function, transcription-coupled DNA damage repair, and cellular chloride homeostasis. Comparing the mouse gene list to human RD genes identified in the RetNet database revealed that mouse models are available for 40% of the known human diseases, suggesting opportunities for future research. This work may provide insight into the molecular players and pathways through which PR degenerative disease occurs and may be useful for planning translational studies.
Collapse
Affiliation(s)
- Gayle B. Collin
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Navdeep Gogna
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Bo Chang
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Nattaya Damkham
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Jai Pinkney
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Lillian F. Hyde
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Lisa Stone
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Jürgen K. Naggert
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Patsy M. Nishina
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Correspondence: (P.M.N.); (M.P.K.); Tel.: +1-207-2886-383 (P.M.N.); +1-207-2886-000 (M.P.K.)
| | - Mark P. Krebs
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Correspondence: (P.M.N.); (M.P.K.); Tel.: +1-207-2886-383 (P.M.N.); +1-207-2886-000 (M.P.K.)
| |
Collapse
|