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Chittum JE, Thompson A, Desai UR. Glycosaminoglycan microarrays for studying glycosaminoglycan-protein systems. Carbohydr Polym 2024; 335:122106. [PMID: 38616080 PMCID: PMC11032185 DOI: 10.1016/j.carbpol.2024.122106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/25/2024] [Accepted: 03/26/2024] [Indexed: 04/16/2024]
Abstract
More than 3000 proteins are now known to bind to glycosaminoglycans (GAGs). Yet, GAG-protein systems are rather poorly understood in terms of selectivity of recognition, molecular mechanism of action, and translational promise. High-throughput screening (HTS) technologies are critically needed for studying GAG biology and developing GAG-based therapeutics. Microarrays, developed within the past two decades, have now improved to the point of being the preferred tool in the HTS of biomolecules. GAG microarrays, in which GAG sequences are immobilized on slides, while similar to other microarrays, have their own sets of challenges and considerations. GAG microarrays are rapidly becoming the first choice in studying GAG-protein systems. Here, we review different modalities and applications of GAG microarrays presented to date. We discuss advantages and disadvantages of this technology, explain covalent and non-covalent immobilization strategies using different chemically reactive groups, and present various assay formats for qualitative and quantitative interpretations, including selectivity screening, binding affinity studies, competitive binding studies etc. We also highlight recent advances in implementing this technology, cataloging of data, and project its future promise. Overall, the technology of GAG microarray exhibits enormous potential of evolving into more than a mere screening tool for studying GAG - protein systems.
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Affiliation(s)
- John E Chittum
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, United States of America; Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, United States of America
| | - Ally Thompson
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, United States of America; Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, United States of America
| | - Umesh R Desai
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, United States of America; Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, United States of America.
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Li D, Tian L, Wang X, Chen M. Macular corneal dystrophy related to novel mutations of CHST6 in a Chinese family and clinical observation after penetrating keratoplasty. BMC Med Genomics 2021; 14:247. [PMID: 34645431 PMCID: PMC8513235 DOI: 10.1186/s12920-021-01095-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 09/28/2021] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Macular corneal dystrophy (MCD) is a rare corneal stromal dystrophy with bilateral progressive vision loss. The pathogenic gene of MCD is carbohydrate sulfotransferase 6 (CHST6). Herein, we report a novel missense mutation and a rare exon deletion mutation in the CHST6 gene in a Chinese family with MCD. METHODS Genomic DNA was extracted from the peripheral blood, and next generation sequencing was used to analyse the gene sequence. The pathogenic mutations were identified in all affected family members. The proband successively received binocular penetrating keratoplasty (PKP), and the corneas were examined by histopathology and colloidal iron staining to prove the diagnosis. A long-term follow-up was made to observe the changes after PKP. RESULTS Genetic analysis demonstrated hemizygous mutations in the proband, including a novel c.520A>C (p.K174Q) missense mutation and a rarely reported exon 3 deletion mutation, which were co-segregated with the MCD phenotypes in the pedigree. The positive colloidal iron staining confirmed the diagnosis of MCD in the proband. However, the clinical phenotype and pathological manifestation of both eyes were different from each other because of complicated keratitis in the left eye. During the nine years of follow-up, visual acuity was improved significantly, and the cornea was transparent without rejection and postoperative recurrence in both eyes. CONCLUSIONS The novel hemizygous mutations were thought to contribute to the loss of CHST6 function, which induced typical clinical and pathological features of MCD. PKP was an effective treatment for MCD.
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Affiliation(s)
- Dewei Li
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, 5 Yan'erdao Road, Qingdao, 266071, China
| | - Le Tian
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, 5 Yan'erdao Road, Qingdao, 266071, China
| | - Xiaochuan Wang
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, 5 Yan'erdao Road, Qingdao, 266071, China
| | - Min Chen
- Qingdao Eye Hospital of Shandong First Medical University, Qingdao, China.
- State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, 5 Yan'erdao Road, Qingdao, 266071, China.
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Huang Y, Yuan L, Cao Y, Tang R, Xu H, Tang Z, Deng H. Novel compound heterozygous mutations in the CHST6 gene cause macular corneal dystrophy in a Han Chinese family. Ann Transl Med 2021; 9:622. [PMID: 33987320 PMCID: PMC8106006 DOI: 10.21037/atm-20-7178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Macular corneal dystrophy (MCD), a rare autosomal recessive disorder, is caused by pathogenic mutations in the carbohydrate sulfotransferase 6 gene (CHST6) and is characterized by bilateral progressive stromal clouding and vision loss. Corneal transplantation is often necessary. This study aimed to identify disease-causing mutations in a Han-Chinese MCD patient. METHODS A 37-year-old female diagnosed with MCD was recruited. The clinical materials were observed and described, and peripheral blood sample was extracted. Whole exome sequencing (WES) and Sanger sequencing were used to reveal genetic defects. The pathogenicity of identified mutations was assessed using in silico analysis. RESULTS The patient had typical features of MCD, including decreased vision, multiple irregular gray-white corneal opacities, and corneal thinning. A novel nonsense mutation c.544C>T (p.Gln182Ter) and a validated missense mutation c.631C>G (p.Arg211Gly) were identified in the CHST6 gene coding region, both classified as "pathogenic" following the American College of Medical Genetics and Genomics standards and guidelines. CONCLUSIONS This study reports a Han-Chinese MCD patient with a novel nonsense mutation c.544C>T (p.Gln182Ter) and a recurrent missense mutation c.631C>G (p.Arg211Gly), which expand the spectrum of genetic mutations. The results of this study extend genotype-phenotype correlations between the CHST6 gene mutations and MCD clinical findings, contributing to a more accurate diagnosis and the development of potential gene-targeted MCD therapies. KEYWORDS Carbohydrate sulfotransferase 6 gene (CHST6); compound heterozygous mutations; Han Chinese family; macular corneal dystrophy (MCD).
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Affiliation(s)
- Yanxia Huang
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Lamei Yuan
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Yanna Cao
- Department of Ophthalmology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Renhong Tang
- Department of Ophthalmology, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Hongbo Xu
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Ziqian Tang
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha, China
| | - Hao Deng
- Center for Experimental Medicine, the Third Xiangya Hospital, Central South University, Changsha, China;,Department of Neurology, the Third Xiangya Hospital, Central South University, Changsha, China;,Disease Genome Research Center, Central South University, Changsha, China
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Safari I, Baradaran-Rafii A, Issazadeh-Navikas S, Elahi E. CHST6 mutations identified in Iranian MCD patients and CHST6 mutations reported worldwide identify targets for gene editing approaches including the CRISPR/Cas system. Int Ophthalmol 2020; 40:2223-2235. [PMID: 32472422 DOI: 10.1007/s10792-020-01401-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/25/2020] [Indexed: 12/19/2022]
Abstract
PURPOSE To identify CHST6 mutations in Iranians macular corneal dystrophy (MCD) patients and also to assess distribution of amino acids in the encoded protein that are affected by CHST6 mutations reported hitherto in various populations in order to predict gene regions that may be appropriate targets for gene editing approaches including the CRISPR/Cas system. The analysis will also reveal biologically and functionally important regions of the protein. METHODS Mutation screening of CHST6 by sequencing was performed on 21 Iranian MCD-affected probands. Previously reported MCD causing CHST6 mutations were identified by searches in NCBI. RESULTS Nineteen CHST6 mutations were found among the 21 Iranian patients, most of which were missense mutations and six of which were novel. Totally, 189 mutations among 375 MCD patients have been found worldwide, and 134 of these are missense mutations. The distribution of 88 amino acids affected by missense mutations along the length of the encoded protein was not random, and four regions of possible mutation clustering were noted. 25% of patients harbored mutations in a DNA region consisting of only 36 nucleotides. CONCLUSION Similar to most populations, CHST6 mutations among Iranians are very heterogeneous as indicated by finding 19 different mutations among 21 MCD patients. Nevertheless, identification of four potential mutation clusters identifies regions that are most suitable for gene therapy targeting by the CRISPR/Cas approach. Additionally, the mutation clusters identify regions with potential structural and/or functional importance. Consistent with this, the amino acids in these regions are well conserved among various membrane-bound sulfotransferases.
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Affiliation(s)
- Iman Safari
- School of Biology, University College of Science, University of Tehran, Enghelab Ave, Tehran, 1417614411, Iran
| | | | - Shohreh Issazadeh-Navikas
- Neuroinflammation Unit, Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Elahe Elahi
- School of Biology, University College of Science, University of Tehran, Enghelab Ave, Tehran, 1417614411, Iran.
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Puri S, Coulson-Thomas YM, Gesteira TF, Coulson-Thomas VJ. Distribution and Function of Glycosaminoglycans and Proteoglycans in the Development, Homeostasis and Pathology of the Ocular Surface. Front Cell Dev Biol 2020; 8:731. [PMID: 32903857 PMCID: PMC7438910 DOI: 10.3389/fcell.2020.00731] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 07/15/2020] [Indexed: 12/20/2022] Open
Abstract
The ocular surface, which forms the interface between the eye and the external environment, includes the cornea, corneoscleral limbus, the conjunctiva and the accessory glands that produce the tear film. Glycosaminoglycans (GAGs) and proteoglycans (PGs) have been shown to play important roles in the development, hemostasis and pathology of the ocular surface. Herein we review the current literature related to the distribution and function of GAGs and PGs within the ocular surface, with focus on the cornea. The unique organization of ECM components within the cornea is essential for the maintenance of corneal transparency and function. Many studies have described the importance of GAGs within the epithelial and stromal compartment, while very few studies have analyzed the ECM of the endothelial layer. Importantly, GAGs have been shown to be essential for maintaining corneal homeostasis, epithelial cell differentiation and wound healing, and, more recently, a role has been suggested for the ECM in regulating limbal stem cells, corneal innervation, corneal inflammation, corneal angiogenesis and lymphangiogenesis. Reports have also associated genetic defects of the ECM to corneal pathologies. Thus, we also highlight the role of different GAGs and PGs in ocular surface homeostasis, as well as in pathology.
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Affiliation(s)
- Sudan Puri
- College of Optometry, University of Houston, Houston, TX, United States
| | - Yvette M Coulson-Thomas
- Molecular Biology Section, Department of Biochemistry, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Tarsis F Gesteira
- College of Optometry, University of Houston, Houston, TX, United States.,Optimvia, LLC, Batavia, OH, United States
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Zhang J, Wu D, Li Y, Fan Y, Dai Y, Xu J. A comprehensive evaluation of 181 reported CHST6 variants in patients with macular corneal dystrophy. Aging (Albany NY) 2019; 11:1019-1029. [PMID: 30716718 PMCID: PMC6382428 DOI: 10.18632/aging.101807] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/25/2019] [Indexed: 01/16/2023]
Abstract
Macular corneal dystrophy (MCD) is an autosomal recessive disease featured by bilateral progressive stromal clouding and loss of vision, consequently necessitating corneal transplantation. Variants in CHST6 gene have been recognized as the most critical genetic components in MCD. Although many CHST6 variants have been described until now, the detailed mechanisms underlying MCD are still far from understood. In this study, we integrated all the reported CHST6 variants described in 408 MCD cases, and performed a comprehensive evaluation to better illustrate the causality of these variants. The results showed that majority of these variants (165 out of 181) could be classified as pathogenic or likely pathogenic. Interestingly, we also identified several disease causal variants with ethnic specificity. In addition, the results underscored the strong correlation between mutant frequency and residue conservation in the general population (Spearman's correlation coefficient = -0.311, P = 1.20E-05), thus providing potential candidate targets for further genetic manipulation. The current study highlighted the demand of further functional investigations to evaluate the causality of CHST6 variants, so as to promote earlier accurate diagnosis of MCD and future development of potential targets for genetic therapy.
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Affiliation(s)
- Jing Zhang
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Dan Wu
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Yue Li
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Yidan Fan
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Yiqin Dai
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Jianjiang Xu
- Department of Ophthalmology and Visual Science, Eye Institute, Eye and ENT Hospital, Shanghai Medical College of Fudan University, NHC Key Laboratory of Myopia (Fudan University), Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
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Caterson B, Melrose J. Keratan sulfate, a complex glycosaminoglycan with unique functional capability. Glycobiology 2018; 28:182-206. [PMID: 29340594 PMCID: PMC5993099 DOI: 10.1093/glycob/cwy003] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 12/20/2017] [Accepted: 01/08/2018] [Indexed: 12/19/2022] Open
Abstract
From an evolutionary perspective keratan sulfate (KS) is the newest glycosaminoglycan (GAG) but the least understood. KS is a sophisticated molecule with a diverse structure, and unique functional roles continue to be uncovered for this GAG. The cornea is the richest tissue source of KS in the human body but the central and peripheral nervous systems also contain significant levels of KS and a diverse range of KS-proteoglycans with essential functional roles. KS also displays important cell regulatory properties in epithelial and mesenchymal tissues and in bone and in tumor development of diagnostic and prognostic utility. Corneal KS-I displays variable degrees of sulfation along the KS chain ranging from non-sulfated polylactosamine, mono-sulfated and disulfated disaccharide regions. Skeletal KS-II is almost completely sulfated consisting of disulfated disaccharides interrupted by occasional mono-sulfated N-acetyllactosamine residues. KS-III also contains highly sulfated KS disaccharides but differs from KS-I and KS-II through 2-O-mannose linkage to serine or threonine core protein residues on proteoglycans such as phosphacan and abakan in brain tissue. Historically, the major emphasis on the biology of KS has focused on its sulfated regions for good reason. The sulfation motifs on KS convey important molecular recognition information and direct cell behavior through a number of interactive proteins. Emerging evidence also suggest functional roles for the poly-N-acetyllactosamine regions of KS requiring further investigation. Thus further research is warranted to better understand the complexities of KS.
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Affiliation(s)
- Bruce Caterson
- Connective Tissue Biology Laboratories, School of Biosciences, College of Biological & Life Sciences, Cardiff University, Cardiff, Wales, UK
| | - James Melrose
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute of Medical Research, Northern Sydney Local Health District, St. Leonards, NSW, Australia
- Sydney Medical School, Northern, The University of Sydney, Royal North Shore Hospital, St. Leonards, NSW, Australia
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
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Tetas Pont R, Downs L, Pettitt L, Busse C, Mellersh CS. A Carbohydrate Sulfotransferase-6 (CHST6) gene mutation is associated with Macular Corneal Dystrophy in Labrador Retrievers. Vet Ophthalmol 2016; 19:488-492. [PMID: 26585178 DOI: 10.1111/vop.12332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
PURPOSE To locate and identify variants associated with macular corneal dystrophy (MCD) in Labrador Retriever (LR) dogs, in the candidate gene carbohydrate sulfotransferase-6 (CHST6). METHODS The single coding exon of canine CHST6 was sequenced in one affected LR with MCD and one control LR clinically clear of ocular disease. A further 71 control LR with unknown clinical status were sequenced for the putative causal variant in CHST6. A TaqMan SNP genotyping assay was developed and used to screen an additional 84 dogs (five affected LR and 79 clinically clear LR). Finally, the variant was screened in a third cohort of 89 unrelated LR with unknown clinical status to estimate its allele frequency in the population of LR in the United Kingdom. RESULTS A single nucleotide polymorphism (SNP) was identified within the coding exon of CHST6, resulting in a missense mutation (c.814C>A, p.R272S). All six LR affected with MCD were homozygous for the mutant allele, while 140/151 control LR were homozygous for the wild-type allele and 11/151 were heterozygous for the mutation, indicating an association with MCD (P < 10-5 ). The mutant allele was present in the unrelated LR cohort at a frequency of 0.017, suggesting carrier and affection rates of 3.3% and 0.028%, respectively. CONCLUSIONS A missense mutation in the CHST6 gene is strongly associated with autosomal recessive MCD in the LR.
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Affiliation(s)
- Roser Tetas Pont
- Comparative Ophthalmology Unit, Animal Health Trust, Lanwades Park, Kentford, CB8 7UU, UK.
| | - Louise Downs
- Canine Genetics, Animal Health Trust, Lanwades Park, Kentford, CB8 7UU, UK
| | - Louise Pettitt
- Canine Genetics, Animal Health Trust, Lanwades Park, Kentford, CB8 7UU, UK
| | - Claudia Busse
- Comparative Ophthalmology Unit, Animal Health Trust, Lanwades Park, Kentford, CB8 7UU, UK
| | - Cathryn S Mellersh
- Canine Genetics, Animal Health Trust, Lanwades Park, Kentford, CB8 7UU, UK
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Carstens N, Williams S, Goolam S, Carmichael T, Cheung MS, Büchmann-Møller S, Sultan M, Staedtler F, Zou C, Swart P, Rice DS, Lacoste A, Paes K, Ramsay M. Novel mutation in the CHST6 gene causes macular corneal dystrophy in a black South African family. BMC Med Genet 2016; 17:47. [PMID: 27439461 PMCID: PMC4955246 DOI: 10.1186/s12881-016-0308-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 06/23/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND Macular corneal dystrophy (MCD) is a rare autosomal recessive disorder that is characterized by progressive corneal opacity that starts in early childhood and ultimately progresses to blindness in early adulthood. The aim of this study was to identify the cause of MCD in a black South African family with two affected sisters. METHODS A multigenerational South African Sotho-speaking family with type I MCD was studied using whole exome sequencing. Variant filtering to identify the MCD-causal mutation included the disease inheritance pattern, variant minor allele frequency and potential functional impact. RESULTS Ophthalmologic evaluation of the cases revealed a typical MCD phenotype and none of the other family members were affected. An average of 127 713 variants per individual was identified following exome sequencing and approximately 1.2 % were not present in any of the investigated public databases. Variant filtering identified a homozygous E71Q mutation in CHST6, a known MCD-causing gene encoding corneal N-acetyl glucosamine-6-O-sulfotransferase. This E71Q mutation results in a non-conservative amino acid change in a highly conserved functional domain of the human CHST6 that is essential for enzyme activity. CONCLUSION We identified a novel E71Q mutation in CHST6 as the MCD-causal mutation in a black South African family with type I MCD. This is the first description of MCD in a black Sub-Saharan African family and therefore contributes valuable insights into the genetic aetiology of this disease, while improving genetic counselling for this and potentially other MCD families.
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Affiliation(s)
- Nadia Carstens
- />Sydney Brenner Institute for Molecular Bioscience, University of the Witwatersrand, 2050 Johannesburg, Gauteng South Africa
| | - Susan Williams
- />Division of Ophthalmology, Department of Neurosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Saadiah Goolam
- />Division of Ophthalmology, Department of Neurosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Trevor Carmichael
- />Division of Ophthalmology, Department of Neurosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Ming Sin Cheung
- />Biomarker Development, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Stine Büchmann-Møller
- />Biomarker Development, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Marc Sultan
- />Biomarker Development, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Frank Staedtler
- />Biomarker Development, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Chao Zou
- />Center for Proteomic Chemistry, Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Peter Swart
- />Division of Anatomical Pathology, National Health Laboratory Services and University of the Witwatersrand, Johannesburg, South Africa
| | - Dennis S. Rice
- />Novartis Institutes for Biomedical Research, Cambridge, USA
| | - Arnaud Lacoste
- />Novartis Institutes for Biomedical Research, Cambridge, USA
| | - Kim Paes
- />Novartis Institutes for Biomedical Research, Cambridge, USA
| | - Michèle Ramsay
- />Sydney Brenner Institute for Molecular Bioscience, University of the Witwatersrand, 2050 Johannesburg, Gauteng South Africa
- />Division of Human Genetics, National Health Laboratory Service and Faculty of Health Sciences, University of the Witwatersrand, 2050 Johannesburg, Gauteng South Africa
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Park SH, Ahn YJ, Chae H, Kim Y, Kim MS, Kim M. Molecular analysis of the CHST6 gene in Korean patients with macular corneal dystrophy: Identification of three novel mutations. Mol Vis 2015; 21:1201-9. [PMID: 26604660 PMCID: PMC4626780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 10/22/2015] [Indexed: 11/02/2022] Open
Abstract
PURPOSE To identify the underlying genetic defect in Korean patients with macular corneal dystrophy (MCD). METHODS Genomic DNA was isolated from peripheral blood leukocytes of seven patients from six unrelated families with MCD (three men and four women). Polymerase chain reaction was performed for coding regions of the carbohydrate sulfotransferase (CHST6), gene followed by bidirectional sequencing. Targeted mutational analysis (exons 4, 11-12, 14) of the transforming growth factor, beta-induced (TGFBI) gene was performed for all patients. RESULTS All seven patients were found to have compound heterozygous mutations in the CHST6 gene. In addition to six previously reported mutations, c.95C>A (p.Ser32*), c.521A>G (p.Lys174Arg), c.557C>G (p.Pro186Arg), c.613C>T (p.Arg205Trp), c.820G>A (p.Glu274Lys), and c.1072T>C (p.Tyr358His), three novel mutations were identified in this study, including two missense mutations, c.353C>T (p.Ser118Phe) and c.922C>T (p.His308Tyr), and one frameshift mutation, c.786delC (p.L264Cfs*117). Among the three novel mutations, only the c.353C>T mutation had been reported in the Exon Aggregation Consortium database at an extremely low frequency of 0.00005072. In addition, these three novel mutations were absent from controls in 1,000 genomes, dbSNP, and the TIARA genome database, which is a Korean personal genome database. The most frequent mutation was c.613C>T (p.Arg205Trp), revealed in four unrelated Korean families, which has not previously been reported in other populations. No mutations were detected in the TGFBI gene. DISCUSSION This is the first report on genetic analysis of Korean MCD patients. Three novel and six previously reported disease-causing CHST6 mutations were identified, which expands the mutational spectrum of MCD.
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Affiliation(s)
- Shin Hae Park
- Department of Ophthalmology and Visual Science, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ye Jin Ahn
- Department of Ophthalmology and Visual Science, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Hyojin Chae
- Department of Laboratory Medicine, College of Medicine, Seoul St, Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Yonggoo Kim
- Department of Laboratory Medicine, College of Medicine, Seoul St, Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Man Soo Kim
- Department of Ophthalmology and Visual Science, College of Medicine, Seoul St. Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
| | - Myungshin Kim
- Department of Laboratory Medicine, College of Medicine, Seoul St, Mary’s Hospital, The Catholic University of Korea, Seoul, Republic of Korea
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