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Chang MS, Jun I, Kim EK. Mini-Review: Clinical Features and Management of Granular Corneal Dystrophy Type 2. KOREAN JOURNAL OF OPHTHALMOLOGY 2023; 37:340-347. [PMID: 37336511 PMCID: PMC10427907 DOI: 10.3341/kjo.2023.0032] [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: 03/17/2023] [Revised: 04/28/2023] [Accepted: 05/23/2023] [Indexed: 06/21/2023] Open
Abstract
Granular corneal dystrophy type 2 (GCD2) is an autosomal dominant corneal stromal dystrophy that is caused by p.Arg124His mutation of transforming growth factor β induced (TGFBI) gene. It is characterized by well demarcated granular shaped opacities in central anterior stroma and as the disease progresses, extrusion of the deposits results in ocular pain due to corneal epithelial erosion. Also, diffuse corneal haze which appears late, causes decrease in visual acuity. The prevalence of GCD2 is high in East Asia including Korea. Homozygous patients show a severe phenotype from an early age, and the heterozygote phenotype varies among patients, depending on several types of compound heterozygous TGFBI mutations. In the initial stage, conservative treatments such as artificial tears, antibiotic eye drops, and bandage contact lenses are used to treat corneal erosion. Different surgical methods are used depending on the depth and extent of the stromal deposits. Phototherapeutic keratectomy removes anterior opacities and is advantageous in terms of its applicability and repeatability. For deeper lesions, deep anterior lamellar keratoplasty can be used as the endothelial layer is not always affected. Recurrence following these treatments are reported within a wide range of rates in different studies due to varying definition of recurrence and follow-up period. In patients who have undergone corneal laser vision-correction surgeries such as photorefractive keratectomy, LASEK, or LASIK including SMILE surgery, corneal opacity exacerbates rapidly with severe deterioration of visual acuity. Further investigations on new treatments of GCD2 are necessary.
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Affiliation(s)
- Myung Soo Chang
- Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul,
Korea
| | - Ikhyun Jun
- Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul,
Korea
- Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul,
Korea
| | - Eung Kweon Kim
- Corneal Dystrophy Research Institute, Yonsei University College of Medicine, Seoul,
Korea
- Saevit Eye Hospital, Goyang,
Korea
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Generation of mouse model of TGFBI-R124C corneal dystrophy using CRISPR/Cas9-mediated homology-directed repair. Sci Rep 2020; 10:2000. [PMID: 32029872 PMCID: PMC7005300 DOI: 10.1038/s41598-020-58876-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/06/2019] [Indexed: 11/12/2022] Open
Abstract
Mutations in transforming growth factor-beta-induced (TGFBI) gene cause clinically distinct types of corneal dystrophies. To delineate the mechanisms driving these dystrophies, we focused on the R124C mutation in TGFBI that causes lattice corneal dystrophy type1 (LCD1) and generated novel transgenic mice harbouring a single amino acid substitution of arginine 124 with cysteine in TGFBI via ssODN-mediated base-pair substitution using CRISPR/Cas9 technology. Eighty percent of homozygous and 9.1% of heterozygous TGFBI-R124C mice developed a corneal opacity at 40 weeks of age. Hematoxylin and eosin and Masson trichrome staining showed eosinophilic deposits in subepithelial corneal stroma that stained negative for Congo-red. Although amyloid deposition was not observed in TGFBI-R124C mice, irregular amorphous deposits were clearly observed via transmission electron microscopy near the basement membrane. Interestingly, we found that the corneal deposition of TGFBI protein (TGFBIp) was significantly increased in homozygous TGFBI-R124C mice, suggesting a pathogenic role for the mutant protein accumulation. Furthermore, as observed in the LCD1 patients, corneal epithelial wound healing was significantly delayed in TGFBI-R124C mice. In conclusion, our novel mouse model of TGFBI-R124C corneal dystrophy reproduces features of the human disease. This mouse model will help delineate the pathogenic mechanisms of human corneal dystrophy.
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Dammacco R, Merlini G, Lisch W, Kivelä TT, Giancipoli E, Vacca A, Dammacco F. Amyloidosis and Ocular Involvement: an Overview. Semin Ophthalmol 2019; 35:7-26. [PMID: 31829761 DOI: 10.1080/08820538.2019.1687738] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Purpose: To describe the ophthalmic manifestations of amyloidosis and the corresponding therapeutic measures.Methods: The 178 patients included in the study had different types of amyloidosis, diagnosed at a single internal medicine institution (Bari, Italy). To provide a comprehensive review of the types of amyloidosis that can be associated with ocular involvement, the images and clinical descriptions of patients with amyloidosis structurally related to gelsolin, keratoepithelin and lactoferrin were obtained in collaborations with the ophthalmology departments of hospitals in Mainz (Germany) and Helsinki (Finland).Results: Overall, ocular morbidity was detected in 41 of the 178 patients with amyloidosis (23%). AL amyloidosis was diagnosed in 18 patients with systemic disease, 3 with multiple myeloma, and 11 with localized amyloidosis. AA amyloidosis was detected in 2 patients with rheumatoid arthritis and 3 with Behçet syndrome, and transthyretin amyloidosis in 4 patients. The treatment of AL amyloidosis is based on chemotherapy to suppress the production of amyloidogenic L-chains and on surgical excision of orbital or conjunctival masses. AA amyloidosis is managed by targeting the underlying condition. Vitreous opacities and additional findings of ocular involvement in patients with transthyretin amyloidosis indicate the need for pars plana vitrectomy. Gelsolin amyloidosis, characterized by lattice corneal amyloidosis and polyneuropathy, results in recurrent keratitis and corneal scarring, such that keratoplasty is inevitable. In patients with lattice corneal dystrophies associated with amyloid deposits of keratoepithelin fragments, corneal transparency is compromised by deposits of congophilic material in the subepithelial layer and deep corneal stroma. Patients with established corneal opacities are treated by corneal transplantation, but the prognosis is poor because recurrent corneal deposits are possible after surgery. In patients with gelatinous drop-like dystrophy, the amyloid fibrils that accumulate beneath the corneal epithelium consist of lactoferrin and can severely impair visual acuity. Keratoplasty and its variants are performed for visual rehabilitation.Conclusion: A routine ophthalmic follow-up is recommended for all patients with established or suspected amyloidosis, independent of the biochemical type of the amyloid. Close collaboration between the ophthalmologist and the internist will facilitate a more precise diagnosis of ocular involvement in amyloidosis and allow the multidisciplinary management of these patients.Abbreviations: CD: corneal dystrophy; CLA: corneal lattice amyloidosis; CNS: central nervous system; CT: computed tomography; FAP: familial amyloidotic polyneuropathy; GDLCD: gelatinous drop-like corneal dystrophy; GLN: gelsolin; LCD: lattice corneal dystrophy; MRI: magnetic resonance imaging; OLT: orthotopic liver transplantation; TEM: transmission electron microscopy; TGFBI: transforming growth factor β induced; TTR: transthyretin.
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Affiliation(s)
- Rosanna Dammacco
- Department of Ophthalmology and Neuroscience, University of Bari "Aldo Moro", Medical School, Bari, Italy
| | - Giampaolo Merlini
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Walter Lisch
- Department of Ophthalmology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Tero T Kivelä
- Department of Ophthalmology, University of Helsinki, Helsinki, Finland.,Helsinki University Central Hospital, Helsinki, Finland
| | - Ermete Giancipoli
- Department of Biomedical Sciences, Ophthalmology Unit, University of Sassari, Sassari, Italy
| | - Angelo Vacca
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Medical School, Bari, Italy
| | - Franco Dammacco
- Department of Biomedical Sciences and Human Oncology, University of Bari "Aldo Moro", Medical School, Bari, Italy
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Kheir V, Cortés-González V, Zenteno JC, Schorderet DF. Mutation update: TGFBI pathogenic and likely pathogenic variants in corneal dystrophies. Hum Mutat 2019; 40:675-693. [PMID: 30830990 DOI: 10.1002/humu.23737] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 02/26/2019] [Accepted: 02/28/2019] [Indexed: 01/07/2023]
Abstract
Human transforming growth factor β-induced (TGFBI), is a gene responsible for various corneal dystrophies. TGFBI produces a protein called TGFBI, which is involved in cell adhesion and serves as a recognition sequence for integrins. An alteration in cell surface interactions could be the underlying cause for the progressive accumulation of extracellular deposits in different layers of the cornea with the resulting changes of refractive index and transparency. To this date, 69 different pathogenic or likely pathogenic variants in TGFBI have been identified in a heterozygous or homozygous state in various corneal dystrophies, including a novel variant reported here. All disease-associated variants were inherited as autosomal-dominant traits but one; this latter was inherited as an autosomal recessive trait. Most corneal dystrophy-associated variants are located at amino acids Arg124 and Arg555. To keep the list of corneal dystrophy-associated variant current, we generated a locus-specific database for TGFBI (http://databases.lovd.nl/shared/variants/TGFBI) containing all pathogenic and likely pathogenic variants reported so far. Non-disease-associated variants are described in specific databases, like gnomAD and ExAC but are not listed here. This article presents the most recent up-to-date list of disease-associated variants.
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Affiliation(s)
- Valeria Kheir
- Institute for Research in Ophthalmology, Sion, Switzerland.,Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Vianney Cortés-González
- Department of Genetics, Hospital "Dr. Luis Sanchez Bulnes", Asociación Para Evitar la Ceguera en México, Mexico City, Mexico
| | - Juan C Zenteno
- Department of Genetics, Institute of Ophthalmology "Conde de Valenciana", Mexico City, Mexico.,Department of Biochemistry, Faculty of Medicine, UNAM, Mexico City, Mexico
| | - Daniel F Schorderet
- Institute for Research in Ophthalmology, Sion, Switzerland.,Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.,Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Shukla S, Tavakkoli F, Singh V, Sangwan VS. Mesenchymal stem cell therapy for corneal diseases. Expert Opin Orphan Drugs 2016. [DOI: 10.1080/21678707.2016.1215906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Sachin Shukla
- Prof. Brien Holden Eye Research Centre, Centre for Ocular Regeneration, Hyderabad Eye Research Foundation, Tej Kohli Cornea Institute, L.V. Prasad Eye Institute, Hyderabad, India
| | - Fatemeh Tavakkoli
- Prof. Brien Holden Eye Research Centre, Centre for Ocular Regeneration, Hyderabad Eye Research Foundation, Tej Kohli Cornea Institute, L.V. Prasad Eye Institute, Hyderabad, India
- Centre for Genetic Disorders, Banaras Hindu University, Varanasi, India
| | - Vivek Singh
- Prof. Brien Holden Eye Research Centre, Centre for Ocular Regeneration, Hyderabad Eye Research Foundation, Tej Kohli Cornea Institute, L.V. Prasad Eye Institute, Hyderabad, India
| | - Virender Singh Sangwan
- Prof. Brien Holden Eye Research Centre, Centre for Ocular Regeneration, Hyderabad Eye Research Foundation, Tej Kohli Cornea Institute, L.V. Prasad Eye Institute, Hyderabad, India
- Srujana-Center for Innovation, Tej Kohli Cornea Institute, L. V. Prasad Eye Institute, Hyderabad, India
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Kamiya K, Kobashi H, Igarashi A, Shoji N, Shimizu K. Effect of Light Scattering and Higher-order Aberrations on Visual Performance in Eyes with Granular Corneal Dystrophy. Sci Rep 2016; 6:24677. [PMID: 27086550 PMCID: PMC4834530 DOI: 10.1038/srep24677] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 04/04/2016] [Indexed: 11/09/2022] Open
Abstract
This study was aimed to assess the relationship of intraocular forward scattering, corneal backward scattering, and corneal higher-order aberrations (HOAs) with corrected distance visual acuity (CDVA) in eyes with granular corneal dystrophy (GCD). We retrospectively examined forty two eyes of 42 consecutive patients who diagnosed GCD, and age-matched 20 eyes of 20 healthy subjects. We assessed objective scattering index (OSI) using the double-pass instrument (OQAS II, Visiometrics), corneal densitometry (CD) using the Scheimpflug rotating camera (Pentacam HR, Oculus), and corneal HOAs using the Hartmann-Shack aberrometry (KR-9000, Topcon). The OSI, CD, and corneal HOAs were significantly larger in the GCD group than those in the control group (Mann-Whitney U test, p < 0.001). We found significant correlations of logMAR CDVA with the OSI (Spearman correlation coefficient r = 0.577, p < 0.001), and with the CD (r = 0.340, p = 0.028), but no significant association with corneal HOAs (r = 0.061, p = 0.701). Intraocular forward scattering, corneal backward scattering, and corneal HOAs in eyes with GCD were higher than that in normal eyes. The CDVA was significantly correlated with intraocular forward scattering, but not with corneal HOAs in eyes with GCD, suggesting that light scattering, especially forward scattering, plays a more vital role in visual performance than corneal aberrations in eyes with GCD.
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Affiliation(s)
- Kazutaka Kamiya
- Department of Ophthalmology, University of Kitasato School of Medicine, Japan
| | - Hidenaga Kobashi
- Department of Ophthalmology, University of Kitasato School of Medicine, Japan
| | - Akihito Igarashi
- Department of Ophthalmology, University of Kitasato School of Medicine, Japan
| | - Nobuyuki Shoji
- Kitasato University School of Allied Health Sciences, Kanagawa, Japan
| | - Kimiya Shimizu
- Department of Ophthalmology, University of Kitasato School of Medicine, Japan
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pH Induced Conformational Transitions in the Transforming Growth Factor β-Induced Protein (TGFβIp) Associated Corneal Dystrophy Mutants. Sci Rep 2016; 6:23836. [PMID: 27030015 PMCID: PMC4814907 DOI: 10.1038/srep23836] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 02/12/2016] [Indexed: 11/24/2022] Open
Abstract
Most stromal corneal dystrophies are associated with aggregation and deposition of the mutated transforming growth factor-β induced protein (TGFβIp). The 4th_FAS1 domain of TGFβIp harbors ~80% of the mutations that forms amyloidogenic and non-amyloidogenic aggregates. To understand the mechanism of aggregation and the differences between the amyloidogenic and non-amyloidogenic phenotypes, we expressed the 4th_FAS1 domains of TGFβIp carrying the mutations R555W (non-amyloidogenic) and H572R (amyloidogenic) along with the wild-type (WT). R555W was more susceptible to acidic pH compared to H572R and displayed varying chemical stabilities with decreasing pH. Thermal denaturation studies at acidic pH showed that while WT did not undergo any conformational transition, the mutants exhibited a clear pH-dependent irreversible conversion from αβ conformation to β-sheet oligomers. The β-oligomers of both mutants were stable at physiological temperature and pH. Electron microscopy and dynamic light scattering studies showed that β-oligomers of H572R were larger compared to R555W. The β-oligomers of both mutants were cytotoxic to primary human corneal stromal fibroblast (pHCSF) cells. The β-oligomers of both mutants exhibit variations in their morphologies, sizes, thermal and chemical stabilities, aggregation patterns and cytotoxicities.
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Pathogenesis and treatments of TGFBI corneal dystrophies. Prog Retin Eye Res 2015; 50:67-88. [PMID: 26612778 DOI: 10.1016/j.preteyeres.2015.11.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 11/12/2015] [Accepted: 11/16/2015] [Indexed: 11/22/2022]
Abstract
Transforming growth factor beta-induced (TGFBI) corneal dystrophies are a group of inherited progressive corneal diseases. Accumulation of transforming growth factor beta-induced protein (TGFBIp) is involved in the pathogenesis of TGFBI corneal dystrophies; however, the exact molecular mechanisms are not fully elucidated. In this review article, we summarize the current knowledge of TGFBI corneal dystrophies including clinical manifestations, epidemiology, most common and recently reported associated mutations for each disease, and treatment modalities. We review our current understanding of the molecular mechanisms of granular corneal dystrophy type 2 (GCD2) and studies of other TGFBI corneal dystrophies. In GCD2 corneal fibroblasts, alterations of morphological characteristics of corneal fibroblasts, increased susceptibility to intracellular oxidative stress, dysfunctional and fragmented mitochondria, defective autophagy, and alterations of cell cycle were observed. Other studies of mutated TGFBIp show changes in conformational structure, stability and proteolytic properties in lattice and granular corneal dystrophies. Future research should be directed toward elucidation of the biochemical mechanism of deposit formation, the relationship between the mutated TGFBIp and the other materials in the extracellular matrix, and the development of gene therapy and pharmaceutical agents.
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Development of a Transgenic Mouse with R124H Human TGFBI Mutation Associated with Granular Corneal Dystrophy Type 2. PLoS One 2015. [PMID: 26197481 PMCID: PMC4511001 DOI: 10.1371/journal.pone.0133397] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To investigate the phenotype and predisposing factors of a granular corneal dystrophy type 2 transgenic mouse model. METHODS Human TGFBI cDNA with R124H mutation was used to make a transgenic mouse expressing human protein (TGFBIR124H mouse). Reverse transcription PCR (RT-PCR) was performed to analyze TGFBIR124H expression. A total of 226 mice including 23 homozygotes, 106 heterozygotes and 97 wild-type mice were examined for phenotype. Affected mice were also examined by histology, immunohistochemistry and electron microcopy. RESULTS RT-PCR confirmed the expression of TGFBIR124H in transgenic mice. Corneal opacity defined as granular and lattice deposits was observed in 45.0% of homozygotes, 19.4% of heterozygotes. The incidence of corneal opacity was significantly higher in homozygotes than in heterozygotes (p = 0.02). Histology of affected mice was similar to histology of human disease. Lesions were Congo red and Masson Trichrome positive, and were observed as a deposit of amorphous material by electron microscopy. Subepithelial stroma was also stained with thioflavin T and LC3, a marker of autophagy activation. The incidence of corneal opacity was higher in aged mice in each group. Homozygotes were not necessarily more severe than heterozygotes, which deffers from human cases. CONCLUSIONS We established a granular corneal dystrophy type 2 mouse model caused by R124H mutation of human TGFBI. Although the phenotype of this mouse model is not equivalent to that in humans, further studies using this model may help elucidate the pathophysiology of this disease.
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Lakshminarayanan R, Chaurasia SS, Anandalakshmi V, Chai SM, Murugan E, Vithana EN, Beuerman RW, Mehta JS. Clinical and genetic aspects of the TGFBI-associated corneal dystrophies. Ocul Surf 2014; 12:234-51. [PMID: 25284770 DOI: 10.1016/j.jtos.2013.12.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 12/05/2013] [Accepted: 12/05/2013] [Indexed: 11/16/2022]
Abstract
Corneal dystrophies are a group of inherited disorders localized to various layers of the cornea that affect corneal transparency and visual acuity. The deposition of insoluble protein materials in the form of extracellular deposits or intracellular cysts is pathognomic. Mutations in TGFBI are responsible for superficial and stromal corneal dystrophies. The gene product, transforming growth factor β induced protein (TGFBIp) accumulates as insoluble deposits in various forms. The severity, clinicopathogenic variations, age of the onset, and location of the deposits depend on the type of amino acid alterations in the protein. Until 2006, 38 different pathogenic mutants were reported for the TGFBI-associated corneal dystrophies. This number has increased to 63 mutants, reported in more than 30 countries. There is no effective treatment to prevent, halt, or reverse the deposition of TGFBIp. This review presents a complete mutation update, classification of phenotypes, comprehensive reported incidents of various mutations, and current treatment options and their shortcomings. Future research directions and possible approaches to inhibiting disease progression are discussed.
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Affiliation(s)
- R Lakshminarayanan
- Singapore Eye Research Institute, Singapore; SRP Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore
| | - Shyam S Chaurasia
- Singapore Eye Research Institute, Singapore; SRP Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Shu-Ming Chai
- Singapore Eye Research Institute, Singapore; Singapore National Eye Centre, Singapore
| | | | - Eranga N Vithana
- Singapore Eye Research Institute, Singapore; SRP Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Roger W Beuerman
- Singapore Eye Research Institute, Singapore; SRP Neuroscience and Behavioral Disorders, Duke-NUS Graduate Medical School, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jodhbir S Mehta
- Singapore Eye Research Institute, Singapore; Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Singapore National Eye Centre, Singapore; Department of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore.
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Analysis of deposit depth and morphology in granular corneal dystrophy type 2 using fourier domain optical coherence tomography. Cornea 2011; 30:729-38. [PMID: 21242786 DOI: 10.1097/ico.0b013e3182000933] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Granular corneal dystrophy type 2 (GCD2) causes the formation of corneal deposits having 3 different morphological types. We used Fourier domain optical coherence tomography to assess the depths of each type according to the morphology. METHODS A prospective study was performed in 54 eyes of 54 heterozygous patients with GCD2. Corneal deposits of 54 patients with GCD2 were classified into 3 morphological types: type 1, diffuse haze; type 2, granular shape (2 subgroups: type 2a, round granulated and type 2b, round spiculated); and type 3, linear shape (2 subgroups: type 3a, short side branched and type 3b, long side branched). Using Fourier domain optical coherence tomography, we measured the distances from the Bowman layer to the upper surface of the deposits (USBL), to the lower surface of the deposits (LSBL), and the thickness of the deposits (TD). The deposits formed along the flap interface were also examined among 19 patients who had LASIK. RESULTS Types 1 and 2 deposits were always adjacent to the Bowman layer; thus the USBLs for each were 0.0 ± 0.0 μm, whereas that of type 3 deposits was 65.4 ± 48.0 μm (P < 0.0001). The LSBL and TD of linear deposits with long side branches (type 3) (313.3 ± 71.4 and 246.2 ± 71.9 μm) were greater than those of type 1 (47.7 ± 10.2 and 47.7 ± 10.2 μm) and type 2 (91.3 ± 39.5 and 91.3 ± 39.5 μm) (P < 0.0001). There were no differences in the measurements between the subgroups type 2a and type 2b or between types 3a and 3b. USBL of the laser in situ keratomileusis group was 54.5 ± 29.8 μm. CONCLUSIONS The depths of corneal deposits in patients with GCD2 were associated with the morphology of the deposits. The linear deposits were located most deeply in the cornea, followed by granular deposits and diffuse haze moving anteriorly. Several deposits have distinct depths according to the morphological types.
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Long Y, Gu YS, Han W, Li XY, Yu P, Qi M. Genotype-phenotype correlations in Chinese patients with TGFBI gene-linked corneal dystrophy. J Zhejiang Univ Sci B 2011; 12:287-92. [PMID: 21462384 DOI: 10.1631/jzus.b1000154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this paper, we report the clinical and molecular features of the distinct TGFBI (human transforming growth factor β-induced, OMIM No. 601692) gene-linked corneal dystrophy. Altogether, five pedigrees and ten unrelated individuals diagnosed as corneal dystrophy were recruited. Peripheral venous DNA was extracted, and then amplified by polymerase chain reaction (PCR) and scanned for mutation by single-stranded conformation polymorphism (SSCP). Direct DNA sequencing was used to analyze the mutations of the TGFBI gene. In our study, thirty patients from five pedigrees and ten sporadic patients were diagnosed as four TGFBI gene-linked corneal dystrophies of granular corneal dystrophy type I (GGCD I), Avellino corneal dystrophy (ACD), lattice corneal dystrophy type I (LCD I), and lattice corneal dystrophy type IIIA (LCD IIIA), and in total, seven disease-causing mutations, namely R555W, A546D, A546T, and T538P mutations in exon 12, R124H and R124C mutations in exon 4, and P501T mutation in exon 11, were identified, while four polymorphisms of V327V, L472L, F540F, and 1665-1666insC were screened in exons 8, 11, and 12. The study ascertained the tight genotype-phenotype relationship and confirmed the clinical and genetic features of four TGFBI gene-linked corneal dystrophies.
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Affiliation(s)
- Yan Long
- Department of Ophthalmology, the First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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Clinical findings and treatments of granular corneal dystrophy type 2 (avellino corneal dystrophy): a review of the literature. Eye Contact Lens 2011; 36:296-9. [PMID: 20724852 DOI: 10.1097/icl.0b013e3181ef0da0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVES To review the literature about clinical findings and treatments of granular corneal dystrophy type 2 (GCD2). METHODS Various literatures on clinical findings, exacerbations after refractive corneal surgery, and treatment modalities of GCD2 were reviewed. RESULTS GCD2 is an autosomal dominant disease. Mutation of transforming growth factor beta-induced gene, TGFBI, or keratoepithelin gene in human chromosome 5 (5q31) is the key pathogenic process in patient with GCD2. Corneal trauma activates TGFBI and then it overproduces transforming growth factor beta-induced gene protein (TGFBIp), which is main component of the corneal opacity. Refractive corneal surgery is a popular procedure to correct refractive error worldwide. However, several cases about exacerbation of GCD2 after corneal refractive surgery such as photorefractive keratectomy, laser in situ keratomileusis, and laser epithelial keratomileusis have been reported. The opacities deteriorate patient's best-corrected visual acuity. Recurrence-free interval varies many factors such as the type of procedure the patient had received and the genotype of the patient. To treat the opacities in GCD2, phototherapeutic keratectomy, lamellar keratoplasty, deep lamellar keratoplasty, and penetrating keratoplasty (PKP) were used. However, the recurrence is still an unsolved problem. CONCLUSIONS Perfect treatment of exacerbation after corneal surface ablation does not exist until now. To prevent exacerbation, refractive surgeons must do a careful preoperative examination of candidates in refractive surgeries.
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Dalton K, Schneider S, Sorbara L, Jones L. Confocal microscopy and optical coherence tomography imaging of hereditary granular dystrophy. Cont Lens Anterior Eye 2009; 33:33-40. [PMID: 19945908 DOI: 10.1016/j.clae.2009.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 09/26/2009] [Accepted: 09/30/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVES This case report examines the clinical characteristics of hereditary granular dystrophy through the use of slit lamp digital photography, confocal microscopy (CM) and optical coherence tomography (OCT). A review of the literature describing the histopathological and genetic associations of stromal dystrophies, suggest it may be possible to differentiate dystrophies based on their clinical manifestations, and appearances of CM and OCT images, with or without the use of genetic testing. CASE REPORT Two sisters, previously diagnosed with Granular (Groenouw I) Dystrophy, were examined. Examination included the use of digital slit lamp photography, CM and OCT imaging. RESULTS "Breadcrumb" opacities were visualized in the anterior two-thirds of the stroma with all three imaging techniques. Opacities were demonstrated in the posterior third of the stroma with the digital photography and OCT techniques. CONCLUSIONS The digital photography, CM and OCT images support the sister's diagnosis of Granular (Groenouw I) Dystrophy. Currently, genetic and histopathological testing are the only techniques available to determine exactly which corneal dystrophy and gene mutation are present. The results of this case report demonstrate that slit lamp digital photography, combined with CM and OCT may be capable of providing sufficient diagnostic information to diagnose corneal granular dystrophies in a clinical setting.
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Affiliation(s)
- Kristine Dalton
- School of Optometry, University of Waterloo, Ontario, Canada.
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Karring H, Runager K, Valnickova Z, Thøgersen IB, Møller-Pedersen T, Klintworth GK, Enghild JJ. Differential expression and processing of transforming growth factor beta induced protein (TGFBIp) in the normal human cornea during postnatal development and aging. Exp Eye Res 2009; 90:57-62. [PMID: 19788893 DOI: 10.1016/j.exer.2009.09.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 09/07/2009] [Accepted: 09/13/2009] [Indexed: 11/17/2022]
Abstract
Transforming growth factor beta induced protein (TGFBIp, also named keratoepithelin) is an extracellular matrix protein abundant in the cornea. The purpose of this study was to determine the expression and processing of TGFBIp in the normal human cornea during postnatal development and aging. TGFBIp in corneas from individuals ranging from six months to 86 years of age was detected and quantified by immunoblotting. The level of TGFBIp in the cornea increases about 30% between 6 and 14 years of age, and adult corneas contain 0.7-0.8 microg TGFBIp per mg wet tissue. Two-dimensional (2-D) immunoblots of the corneal extracts showed a characteristic "zig-zag" pattern formed by different lower-molecular mass TGFBIp isoforms (30-60 kDa). However, the relative abundance of the different isoforms was different between infant corneas (<1 year) and the child/adult corneas (>6 years). Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) data of TGFBIp isoforms separated on large 2-D gels show that TGFBIp is proteolytically processed from the N-terminus. This observation was supported by in silico 2-D gel electrophoresis showing that sequential proteolytical trimming events from the N-terminus of mature TGFBIp generate TGFBIp isoforms which form a similar "zig-zag" pattern when separated by 2-D polyacrylamide gel electrophoresis (PAGE). This study shows that in humans TGFBIp is more abundant in mature corneas than in the developing cornea and that the processing of TGFBIp changes during postnatal development of the cornea. In addition, TGFBIp appears to be degraded in a highly orchestrated manner in the normal human cornea with the resulting C-terminal fragments being retained in the cornea. The age-related changes in the expression and processing of corneal TGFBIp suggests that TGFBIp may play a role in the postnatal development and maturation of the cornea. Furthermore, these observations may be relevant to the age at which mutant TGFBIp deposits in the cornea in those dystrophies caused by mutations in the transforming growth factor beta induced gene (TGFBI) as well as the mechanisms of corneal protein deposition.
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Affiliation(s)
- Henrik Karring
- Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, University of Southern Denmark, Niels Bohrs Allé 1, DK-5230 Odense M, Denmark
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18
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Double mutation (R124H, N544S) of TGFBI in two sisters with combined expression of Avellino and lattice corneal dystrophies. Mol Vis 2009; 15:974-9. [PMID: 19461933 PMCID: PMC2684562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 05/10/2009] [Indexed: 11/21/2022] Open
Abstract
PURPOSE The R124H mutation of the keratoepithelin gene (TGFBI) causes Avellino corneal dystrophy whereas the N544S mutation of this same gene gives rise to lattice corneal dystrophy. We now report two cases with both R124H and N544S mutations of TGFBI. METHODS Genomic DNA and cDNA were isolated from the proband and family members and were subjected to polymerase chain reaction-mediated amplification of exons 1-17 of TGFBI. The amplification products were directly sequenced. Allele-specific cloning and sequencing were applied to evaluate the compound heterozygous mutation. RESULTS Molecular genetic analysis revealed that the proband and one sister harbored both a heterozygous CGC-->CAC (Arg-->His) mutation at codon 124 and a heterozygous AAT-->AGT (Asn-->Ser) mutation at codon 544 of TGFBI. Slit-lamp examination revealed multiple granular regions of opacity and lattice lines in the corneal stroma of the proband and her sister with the double mutation. Allele-specific cloning and sequencing revealed that the R124H and N544S mutations are on different chromosomes. CONCLUSIONS As far as we are aware, this is the first report of a patient with a double mutation (R124H, N544S) of TGFBI causing an autosomal dominant form of corneal dystrophy. The clinical manifestations of the two cases with both R124H and N544S mutations appeared to be a summation of Avellino and lattice corneal dystrophies.
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Cao W, Ge H, Cui X, Zhang L, Bai J, Fu S, Liu P. Reduced penetrance in familial Avellino corneal dystrophy associated with TGFBI mutations. Mol Vis 2009; 15:70-5. [PMID: 19145249 PMCID: PMC2622714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Accepted: 01/08/2009] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To characterize the clinical phenotype, histopathological features, and molecular genetic basis of an Avellino corneal dystrophy (ACD) in a Chinese family. METHODS A complete ophthalmologic examination was performed in 21 individuals (6 affected and 15 unaffected) of the four-generation family. DNA was obtained from peripheral blood leukocytes of each participant. Genetic analysis included TGFBI polymerase chain reaction (PCR) amplification and automated nucleotidic sequenceing of all 17 exons of genomic DNA. Histological analysis of corneal tissue from the proband was performed after a penetrating keratoplasty. One hundred Chinese controls were scanned for the presence of the R124H mutation by amplifying TGFBI exon 4 and then by direct sequencing of PCR products. RESULTS The proband of the pedigree had phenotypic features consistent with diagnosis of ACD. He was homozygous for the same R124H mutation in TGFBI as previously reported in Japan and European countries. In addition, 4 affected and 7 unaffected individuals carried the same variation in the heterozygous state were identified. None of the 100 control subjects was positive for this mutation. Moreover, a variable expressivity and an apparent non-penetrance were observed in the individuals with heterozygous R124H mutation in our pedigree. After excluding the missed diagnosis or a late onset, it could be interpreted as a reduced penetrance. CONCLUSIONS We reported a novel ACD family which exhibited a reduced penetrance of phenotype in northern China. This outcome supports that although the R124H mutation is one of the genetic causes of the disease, different genetic and environmental factors may influence the expressivity and the penetrance. Uncovering the mechanism may facilitate us to inhibit the occurrence of the corneal dystrophy caused by the R124H mutation in TGFBI, irrespective of the homozygous and heterozygous mutation.
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Affiliation(s)
- Wenping Cao
- Eye hospital, The First Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Hongyan Ge
- Eye hospital, The First Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Xiaobo Cui
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, China
| | - Lu Zhang
- Eye hospital, The First Affiliated Hospital, Harbin Medical University, Harbin, China
| | - Jing Bai
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, China
| | - Songbin Fu
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, China
| | - Ping Liu
- Eye hospital, The First Affiliated Hospital, Harbin Medical University, Harbin, China
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Pampukha VN, Kravchenko SA, Tereshchenko F, Drozhzhina GI, Livshits LA. TGFBI gene mutations in the Ukrainian patients with inherited corneal stromal dystrophies. RUSS J GENET+ 2008. [DOI: 10.1134/s1022795408100104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Aldave AJ, Yellore VS, Sonmez B, Bourla N, Salem AK, Khan MA, Rayner SA, Glasgow BJ. A novel variant of combined granular-lattice corneal dystrophy associated with the Met619Lys mutation in the TGFBI gene. ACTA ACUST UNITED AC 2008; 126:371-7. [PMID: 18332318 DOI: 10.1001/archopht.126.3.371] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To report a novel mutation in TGFBI (GenBank NM_000358), p.Met619Lys, associated with a variant of combined granular-lattice corneal dystrophy. METHODS Slitlamp examination and DNA collection from the proband and affected and unaffected relatives. All 17 exons of TGFBI were amplified and sequenced in the proband. Exon 14 was amplified and sequenced in the proband's family members and in 100 controls. Histopathologic examination of the excised corneal buttons from the proband and 3 family members was also performed. RESULTS Affected individuals demonstrated an age-dependent phenotype, with the progression from central subepithelial needlelike deposits in younger individuals to polymorphic anterior stromal opacities in older family members. Screening of TGFBI in the proband demonstrated a novel mutation, p.Met619Lys, which was also present in all affected family members. Histopathologic examination revealed stromal deposits that stained with the Congo red and Masson trichrome stains as well as an antibody to the protein product of TGFBI. CONCLUSIONS We present a unique corneal dystrophy phenotype associated with the novel p.Met619Lys mutation in TGFBI. Clinical Relevance The atypical and variable phenotype and the demonstration of both hyaline and amyloid stromal deposits indicate that neither clinical nor histopathologic features may be relied on to accurately diagnose and classify the corneal dystrophies.
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Affiliation(s)
- Anthony J Aldave
- Jules Stein Eye Institute, University of California, Los Angeles, CA 90095, USA.
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22
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Alavi A, Elahi E, Rahmati-Kamel M, Karimian F, Rezaei-Kanavi M. Mutation screening of TGFBI in two Iranian Avellino corneal dystrophy pedigrees. Clin Exp Ophthalmol 2008; 36:26-30. [PMID: 18290950 DOI: 10.1111/j.1442-9071.2007.01649.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Genetic analysis and phenotypic features of Avellino corneal dystrophy patients from Japan and some European countries have been published. We report for the first time the genetic analysis and phenotypic features of two Avellino corneal dystrophy pedigrees from the Middle East. METHODS Slit-lamp biomicroscope photographs of cornea were obtained, and corneal tissue sections were stained with masson-trichrome and Congo red. DNA was isolated from peripheral blood leucocytes and exons 4 and 12 of TGFBI were screened for mutations by direct sequencing. RESULTS The probands of the pedigrees had phenotypic features consistent with diagnosis of Avellino corneal dystrophy. They were homozygous for the same R124H mutation in TGFBI as previously reported in Avellino patients from Japan and European countries. Heterozygous carriers of the mutation were identified in the pedigree and shown to have symptoms of disease milder than those of the probands. CONCLUSION The finding of R124H in the Middle Eastern (Iranian) population supports the proposal that perhaps only substitution of histidine for arginine at position 124 of tumour growth factor beta induced protein results in the Avellino corneal dystrophy phenotype. As both probands were originally diagnosed with granular corneal dystrophy, and as heterozygous carriers of R124H were unaware of their disease status prior to genetic analysis, the importance of genetic analysis is emphasized.
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Affiliation(s)
- Afagh Alavi
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
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23
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Moon JW, Kim SW, Kim TI, Cristol SM, Chung ES, Kim EK. Homozygous granular corneal dystrophy type II (Avellino corneal dystrophy): natural history and progression after treatment. Cornea 2008; 26:1095-100. [PMID: 17893542 DOI: 10.1097/ico.0b013e3181484013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To describe the clinical features of homozygous granular corneal dystrophy type II (GCDII) with age and with several kinds of treatment in 18 homozygous patients in several different conditions. METHODS Eighteen homozygous GCDII patients, confirmed with DNA analysis, of 13 families were enrolled. Their clinical features that include age at detection by parents, visual acuity, and disease progression were evaluated. We also studied the recurrence patterns for the 13 patients who underwent phototherapeutic keratectomy, penetrating keratoplasty, lamellar keratoplasty, or deep lamellar keratoplasty. RESULTS The age at detection by the parents ranged from 3 to 5 years; visual loss begins in childhood with progression into the 20s. All of the patients who had undergone surgeries acquired better vision immediately after surgery. Corneal deposits reappeared soon after treatments. Recurrences became progressively more rapid and severe with treatments. CONCLUSIONS The clinical features of homozygous GCDII are characterized by a severe granular type of corneal dystrophy with an early onset and rapid progression. After surgical treatment, recurrence is rapid and severe.
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Affiliation(s)
- Jong Wook Moon
- Corneal Dystrophy Research Institute, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea
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24
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Abstract
The lattice corneal dystrophies (LCD) and granular corneal dystrophies (GCD) are autosomal dominant disorders of the corneal stroma. They are bilateral, progressive conditions characterized by the formation of opacities arising due to the deposition of insoluble material in the corneal stroma leading to visual impairment. The LCDs and GCDs are distinguished from each other and are divided into subtypes on the basis of the clinical appearance of the opacities, clinical features of the disease, and on histopathological staining properties of the deposits. The GCDs and most types of LCD arise from mutations in the transforming growth factor beta-induced (TGFBI) gene on chromosome 5q31. Over 30 mutations causing LCD and GCD have been identified so far in the TGFBI. There are two mutation hotspots corresponding to arginine residues at positions 124 and 555 of the transforming growth factor beta induced protein (TGFBIp) and they are the most frequent sites of mutation in various populations. Mutations at either of these two hotspots result in specific types of LCD or GCD. The majority of identified mutations involve residues in the fourth fasciclin-like domain of TGFBIp.
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Affiliation(s)
- Chitra Kannabiran
- Kallam Anji Reddy Molecular Genetics Laboratory, L.V. Prasad Eye Institute, Hyderabad, India.
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25
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Yamada N, Chikama TI, Morishige N, Yanai R, Nishida T, Inui M, Seki K. Homozygous mutation (L527R) of TGFBI in an individual with lattice corneal dystrophy. Br J Ophthalmol 2005; 89:771-3. [PMID: 15923518 PMCID: PMC1772697 DOI: 10.1136/bjo.2004.056168] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Yoshida S, Yamaji Y, Yoshida A, Noda Y, Kumano Y, Ishibashi T. Rapid genotyping for most common TGFBI mutations with real-time polymerase chain reaction. Hum Genet 2005; 116:518-24. [PMID: 15744520 DOI: 10.1007/s00439-005-1269-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Accepted: 01/05/2005] [Indexed: 01/20/2023]
Abstract
Recent studies of the corneal dystrophies (CDs) have shown that most cases of granular CD, Avellino CD, and lattice CD type I are caused by mutations in the human transforming growth factor beta-induced (TGFBI) gene. The aim of this study was to develop a rapid diagnostic assay to detect mutations in the TGFBI gene. Sixty-six patients from 64 families with TGFBI-associated CD were studied. A primer probe set was designed to examine the genome from exons 4 and 12 of the TGFBI gene in order to identify mutant and wild-type alleles. A region spanning the mutations was amplified by the polymerase chain reaction (PCR) in a commercial cycler. Mutations were then identified by melting curve analysis of the hybrid formed between the PCR product and a specific fluorescent probe. Using this system, we clearly distinguished each CD genotype (homozygous and heterozygous 418G-->A, heterozygous 417C-->T, heterozygous 1710C-->T, and wild-type) of all the patients by means of the clearly distinct melting peaks at different temperatures. One thermal cycling took approximately 54 min, and all results were completely in concordance with the genotypes determined by conventional DNA sequencing. Thus, the technique is accurate and can be used for routine clinical diagnosis. We expect that our new method will help in making precise diagnoses of patients with atypical CDs and aid the revision of the clinical classification of inherited corneal diseases based on the genetic pathogenesis.
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Affiliation(s)
- Shigeo Yoshida
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, 812-8582, Japan.
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Mashima Y, Kawashima M, Yamada M. Electrolytic removal of recurrence of granular corneal dystrophy. Eye (Lond) 2003; 17:975-81. [PMID: 14631404 DOI: 10.1038/sj.eye.6700572] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
AIMS To report the efficacy of corneal electrolysis for the treatment of recurrent corneal opacities at the subepithelial region or at the host-graft interface of the stroma in granular corneal dystrophy (GCD). METHODS In patients with recurrences of opacities at the host-graft interface of the stroma after lamellar keratoplasty, the deep aspect of the graft was partially separated from host tissue to expose the deposits. The graft was everted, and electrolysis was applied directly to remove the deposits attached to both surfaces of the host and the graft. Then the graft was returned to its place and sutured. In patients with diffuse subepithelial opacities following penetrating keratoplasty, electrolysis was applied directly to the corneal surface. RESULTS Deposits in the subepithelial region or at the host-graft interface of the stroma disappeared following treatment, and vision recovered. However, GCD recurred 2-3 years after the treatment. CONCLUSIONS Corneal electrolysis is a simple, easy, and inexpensive way to remove deposits that recur after lamellar or penetrating keratoplasty for GCD.
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Affiliation(s)
- Y Mashima
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
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Wang M, Munier F, Araki-Saski K, Schorderet D. TGFBI gene transcript is transforming growth factor-beta1-responsive and cell density-dependent in a human corneal epithelial cell line. Ophthalmic Genet 2002; 23:237-45. [PMID: 12567266 DOI: 10.1076/opge.23.4.237.13884] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE To determine the roles of transforming growth factor-beta( 1) (TGF-beta(1)), epidermal growth factor (EGF), and cell density on the regulation of the TGFBI gene transcript in a human corneal epithelial cell line (HCE-T). METHODS HCE-T cells (40-50% confluent), which possess the biochemical and morphological phenotype of human corneal epithelial cells, were treated with either TGF-beta(1) (20 ng/ml) or EGF (20 ng/ml) for 0, 24, 48, and 72 h. Total RNA was isolated at each time point from the treated cells and the placebo-treated controls. The TGFBI mRNA transcript level was quantitated using Northern blot analysis. RESULTS TGF-beta(1) upregulates TGFBI gene transcript in this human corneal epithelial cell line, reaching a peak of 2.5-fold of upregulation at 48 h after TGF-beta(1) treatment and a 1.5-fold at 72 h. In contrast, EGF treatment showed no effect on the TGFBI mRNA level. In addition, the TGFBI gene transcript appears to be cell density-dependent because the transcript level shows a trend of reduction as the cell density increases from 40-50% to full confluency. CONCLUSION The TGFBI gene transcript in this human corneal epithelial cell line is upregulated by growth factor TGF-beta( 1), but is not affected by growth factor EGF. Furthermore, cell density appears to be an important regulatory mechanism in controlling the level of TGFBI gene expression in corneal epithelial cells.
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Affiliation(s)
- Ming Wang
- Wang Vision Institute and Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
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Inoue T, Watanabe H, Yamamoto S, Maeda N, Inoue Y, Shimomura Y, Tano Y. Recurrence of corneal dystrophy resulting from an R124H Big-h3 mutation after phototherapeutic keratectomy. Cornea 2002; 21:570-3. [PMID: 12131032 DOI: 10.1097/00003226-200208000-00007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The purpose of the study was to investigate the recurrence-free interval after phototherapeutic keratectomy (PTK) in patients with corneal dystrophies resulting from an Arg124His (R124H) mutation of the Big-h3 gene. METHODS Patients with corneal dystrophy resulting from a genetically confirmed Big-h3 R124H mutation were examined with a slit lamp. The patients were divided into two groups on the basis of the mutation genotype, and the recurrence-free interval was analyzed. RESULTS In the 4 eyes of 3 homozygous patients, the mean (+/- standard deviation [SD]) recurrence-free interval was 9.5 +/- 3.1 months, whereas in the 7 eyes of 4 heterozygous patients it was 38.4 +/- 6.2 months. The former interval was statistically shorter than the latter (Kaplan-Meier survival analysis with log-rank test, p = 0.004). CONCLUSIONS These results strongly suggest that the mutation genotype of Big-h3 gene determined the recurrence-free interval as well as the clinical picture after PTK. Therefore, PTK should be considered for patients with Big-h3 R124H corneal dystrophy, on the basis of the expected recurrence-free interval deduced from molecular analysis of the zygosity of the Big-h3 R124H mutation.
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Affiliation(s)
- Tomoyuki Inoue
- Department of Ophthalmology, Osaka University Medical School E-7, 2-2 Yamadaoka, Suita 565-0871, Osaka, Japan
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30
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Pang CP, Lam DSC. Differential occurrence of mutations causative of eye diseases in the Chinese population. Hum Mutat 2002; 19:189-208. [PMID: 11857735 DOI: 10.1002/humu.10053] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ethnic differences and geographic variations affect the frequencies and nature of human mutations. In the literature, descriptions of causative mutations of eye diseases in the Chinese population are few. In this paper we attempt to reveal molecular information on genetic eye diseases involving Chinese patients from published and unpublished works by us and other groups. Our studies on candidate genes of eye diseases in the Chinese population in Hong Kong include MYOC and TISR for primary open angle glaucoma, RHO and RP1 for retinitis pigmentosa, ABCA4 and APOE for age-related macular degeneration, RB1 for retinoblastoma, APC for familial adenomatous polyposis with congenital hypertrophy of retinal pigment epithelium, BIGH3/TGFBI for corneal dystrophies, PAX6 for aniridia and Reiger syndrome, CRYAA and CRYBB2 for cataracts, and mtDNA for Leber hereditary optic neuropathy. We have revealed novel mutations in most of these genes, and in RHO, RP1, RB1, BIGH3, and PAX6 we have reported mutations that contribute to better understanding of the functions and properties of the respective gene products. We showed absence of MYOC does not necessarily cause glaucoma. No disease causative mutations have been identified in MYOC or ABCA4. There are similarities in the patterns of sequence alterations and phenotype-genotype associations in comparison with other ethnic groups, while the MYOC, RB1, APC, and PAX6 genes have more Chinese-specific sequence alterations. Establishment of a mutation database specific for the Chinese is essential for identification of genetic markers with diagnostic, prognostic, or pharmacological values.
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Affiliation(s)
- Chi Pui Pang
- Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong, China.
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Mashima Y, Kawai M, Yamada M. Corneal electrolysis for recurrence of corneal stromal dystrophy after keratoplasty. Br J Ophthalmol 2002; 86:273-5. [PMID: 11864880 PMCID: PMC1771064 DOI: 10.1136/bjo.86.3.273] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To evaluate corneal electrolysis as a treatment for recurrent diffuse corneal opacities at the host-graft interface of the stroma or at the subepithelial region in two types of granular corneal dystrophy (GCD). METHODS Recurrence developed at the host-graft interface of the stroma after lamellar keratoplasty in a patient with Avellino corneal dystrophy (ACD). At surgery, the deep aspect of the graft in this patient was partially separated from host tissue to expose the deposits, with one third of the host-graft junction left intact. The graft was everted, and electrolysis was applied directly to remove the deposits attached to both surfaces of the host and the graft. Then the graft was returned to its place and sutured. In two patients with homozygous ACD and one patient with the superficial variant of GCD, diffuse subepithelial opacities developed following penetrating keratoplasty. Electrolysis was applied directly to the corneal surface. RESULTS Deposits at the host-graft interface of the stroma and in the subepithelial region disappeared following treatment, and vision recovered in all patients. CONCLUSIONS This method is a simple, easy, and inexpensive way to remove deposits that recur after lamellar or penetrating keratoplasty.
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Affiliation(s)
- Y Mashima
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
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Kiratli H, Irkeç M, Ozgül K, Ogüş A. The phenotype of arg555trp mutation in a large Turkish family with corneal granular dystrophy. Eur J Ophthalmol 2001; 11:333-7. [PMID: 11820303 DOI: 10.1177/112067210101100403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE A large Turkish family with 52 members, 26 of whom had Groenouw type 1 corneal granular dystrophy was evaluated by genetic linkage studies and mutation analyses. Phenotype-genotype correlations were also assessed. METHODS DNA from peripheral blood lymphocytes of 22 family members was used in establishing linkage to chromosome 5q31. Single-strand conformation polymorphism analysis was done to detect mutations in exons 4 and 12 of the human transforming growth factor beta-induced gene located on chromosome 5q31. Automated sequencing was performed on exon 12 of an affected patient. RESULTS Patients yonger than 15 years of age had typical linear, granular opacities whereas adults had coarser, deeper granular stromal deposits. These changes were not associated with recurrent erosions or significant visual disabilities. The family was linked to chromosome 5q31 and a DNA shift was observed on exon 12 of affected patients. CGG to TGG transition producing R555W mutation was found. CONCLUSIONS Segregation of Arg555Trp has been described as causing Groenouw type I corneal dystrophy of variable severity in patients of various ethnic backgrounds. In this large Turkish pedigree, the Arg555Trp mutation was associated with a mild phenotype that became clinically evident at five years of age but which remained asymptomatic in terms of corneal erosions.
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Affiliation(s)
- H Kiratli
- Department of Ophthalmology, School of Medicine, Hacettepe University, Ankara, Turkey.
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Abstract
PURPOSE To indicate important changes in our understanding of the corneal dystrophies. METHODS A review of the literature of the last quarter of a century. RESULTS The earliest clinical classifications of the corneal dystrophies were based on the application of clinical, biological, histochemical, and ultrastructural methods. Since then, the first great impetus to our understanding has come from the application of techniques to map disorders to specific chromosome loci, using polymorphic markers. More recently, using candidate gene and related approaches, it has been possible to identify genes causing several of the corneal dystrophies and the mutations responsible for their phenotypic variation. A notable success has been to show that several important "stromal" dystrophies result from mutations in the gene beta ig-h3, which encodes for the protein keratoepithelin (beta ig-h3). CONCLUSIONS For the corneal dystrophies, as with other inherited disorders, there is room for two sorts of classification system, one based mainly on clinical presentation and the other on an up-to-date understanding of the genetic mechanisms. They are not mutually exclusive. Some developmental corneal disorders are also discussed.
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Affiliation(s)
- A J Bron
- Nuffield Laboratory of Ophthalmology, University of Oxford, UK
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34
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Kaji Y, Amano S, Oshika T, Usui T, Kitagawa M, Mimura T, Matsubara M. Chronic clinical course of two patients with severe corneal dystrophy caused by homozygous R124H mutations in the betaig-h3 gene. Am J Ophthalmol 2000; 129:663-5. [PMID: 10844061 DOI: 10.1016/s0002-9394(00)00372-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To report the chronic clinical course of two patients with homozygous R124H mutations in the betaig-h3 gene. METHODS Case reports. RESULTS Two patients with homozygous R124H mutations in the betaig-h3 gene developed severe juvenile corneal opacities that required keratoplasty. After surgery, corneal opacities recurred and limited the recovery of visual acuity in the chronic follow-up. CONCLUSION In patients with homozygous R124H mutations in the betaig-h3 gene, recurrence of corneal opacities after keratoplasty limits the recovery of visual acuity in the chronic follow-up.
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Affiliation(s)
- Y Kaji
- Department of Ophthalmology, University of Tokyo School of Medicine, Tokyo, Japan
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35
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Gupta SK, Hodge WG. A new clinical perspective of corneal dystrophies through molecular genetics. Curr Opin Ophthalmol 1999; 10:234-41. [PMID: 10621529 DOI: 10.1097/00055735-199908000-00003] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the past 2 years, significant advances have been made in the genetics of corneal dystrophies. Genetic heterogeneity (one disease condition caused by single mutations in any one of multiple genes) and phenotypic diversity (many disease conditions caused by mutations in a single gene) are common emerging themes. Genetic heterogeneity in Meesmann corneal dystrophy was established with the identification of two causative genes, keratins 3 and 12, that encode cytoskeletal proteins. Conversely, mutations in a single gene, keratoepithelin, were found to cause several distinct corneal dystrophies affecting the Bowman layer and the stroma. We present a novel preliminary classification of corneal dystrophies based on molecular etiology. This classification may be useful in understanding the pathogenesis of corneal dystrophies and in developing new strategies to treat these dystrophies.
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Affiliation(s)
- S K Gupta
- University of Ottawa Eye Institute, Ontario, Canada
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Stewart HS, Ridgway AE, Dixon MJ, Bonshek R, Parveen R, Black G. Heterogeneity in granular corneal dystrophy: identification of three causative mutations in the TGFBI (BIGH3) gene-lessons for corneal amyloidogenesis. Hum Mutat 1999; 14:126-32. [PMID: 10425035 DOI: 10.1002/(sici)1098-1004(1999)14:2<126::aid-humu4>3.0.co;2-w] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Six autosomal dominant corneal dystrophies are caused by mutations in the TGFBI (BIGH3) gene on chromosome 5q31: three types of lattice corneal dystrophy (LCD), including type I and type IIIA, granular, Avellino (ACD), and Reis-Bucklers. Initially an exact genotype-phenotype correlation was reported. We report three families, with differing clinical features, all presenting with "granular" corneal dystrophy. We analysed the TGFBI gene by SSCP analysis and direct sequencing in order to further assess the genotype-phenotype correlation. We describe three separate mutations in TGFBI: one novel, one initially described as causing ACD, and one previously described. The novel mutation, R124S, is at the identical position to the mutation causing LCD type I (CDL1). We review the clinical and histological phenotypes of the corneal dystrophies and hypothesize that the ability of a mutation to cause amyloid deposition depends on the location and nature of the mutation. In addition, we suggest that the classification of the granular corneal dystrophies be revised according to mutation type and that ACD should not be classified as a distinct morphological entity.
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Affiliation(s)
- H S Stewart
- Department of Medical Genetics and Regional Genetics Service, St Mary's Hospital, Manchester, UK
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