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Al-Saei O, Malka S, Owen N, Aliyev E, Vempalli FR, Ocieczek P, Al-Khathlan B, Fakhro K, Moosajee M. Increasing the diagnostic yield of childhood glaucoma cases recruited into the 100,000 Genomes Project. BMC Genomics 2024; 25:484. [PMID: 38755526 PMCID: PMC11097485 DOI: 10.1186/s12864-024-10353-8] [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: 12/22/2023] [Accepted: 04/25/2024] [Indexed: 05/18/2024] Open
Abstract
Childhood glaucoma (CG) encompasses a heterogeneous group of genetic eye disorders that is responsible for approximately 5% of childhood blindness worldwide. Understanding the molecular aetiology is key to improving diagnosis, prognosis and unlocking the potential for optimising clinical management. In this study, we investigated 86 CG cases from 78 unrelated families of diverse ethnic backgrounds, recruited into the Genomics England 100,000 Genomes Project (GE100KGP) rare disease cohort, to improve the genetic diagnostic yield. Using the Genomics England/Genomic Medicine Centres (GE/GMC) diagnostic pipeline, 13 unrelated families were solved (13/78, 17%). Further interrogation using an expanded gene panel yielded a molecular diagnosis in 7 more unrelated families (7/78, 9%). This analysis effectively raises the total number of solved CG families in the GE100KGP to 26% (20/78 families). Twenty-five percent (5/20) of the solved families had primary congenital glaucoma (PCG), while 75% (15/20) had secondary CG; 53% of this group had non-acquired ocular anomalies (including iris hypoplasia, megalocornea, ectopia pupillae, retinal dystrophy, and refractive errors) and 47% had non-acquired systemic diseases such as cardiac abnormalities, hearing impairment, and developmental delay. CYP1B1 was the most frequently implicated gene, accounting for 55% (11/20) of the solved families. We identified two novel likely pathogenic variants in the TEK gene, in addition to one novel pathogenic copy number variant (CNV) in FOXC1. Variants that passed undetected in the GE100KGP diagnostic pipeline were likely due to limitations of the tiering process, the use of smaller gene panels during analysis, and the prioritisation of coding SNVs and indels over larger structural variants, CNVs, and non-coding variants.
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Affiliation(s)
- Omayma Al-Saei
- Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
- Department of Human Genetics, Sidra Medicine, PO Box 26999, Doha, Qatar
| | - Samantha Malka
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
| | - Nicholas Owen
- Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
| | - Elbay Aliyev
- Department of Human Genetics, Sidra Medicine, PO Box 26999, Doha, Qatar
| | | | - Paulina Ocieczek
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
| | | | - Khalid Fakhro
- Department of Human Genetics, Sidra Medicine, PO Box 26999, Doha, Qatar
| | - Mariya Moosajee
- Institute of Ophthalmology, University College London, London, EC1V 9EL, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK.
- The Francis Crick Institute, London, NW1 1AT, UK.
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Kumar A, Han Y, Oatts JT. Genetic changes and testing associated with childhood glaucoma: A systematic review. PLoS One 2024; 19:e0298883. [PMID: 38386645 PMCID: PMC10883561 DOI: 10.1371/journal.pone.0298883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/30/2024] [Indexed: 02/24/2024] Open
Abstract
Many forms of childhood glaucoma have been associated with underlying genetic changes, and variants in many genes have been described. Currently, testing is variable as there are no widely accepted guidelines for testing. This systematic review aimed to summarize the literature describing genetic changes and testing practices in childhood glaucoma. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) 2020 guidelines and registered with Prospero (ID CRD42023400467). A comprehensive review of Pubmed, Embase, and Cochrane databases was performed from inception through March 2, 2023 using the search terms: (glaucoma) AND (pediatric OR childhood OR congenital OR child OR infant OR infantile) AND (gene OR genetic OR genotype OR locus OR genomic OR mutation OR variant OR test OR screen OR panel). Information was extracted regarding genetic variants including genotype-phenotype correlation. Risk of bias was assessed using the Newcastle-Ottawa Scale. Of 1,916 records screened, 196 studies met inclusion criteria and 53 genes were discussed. Among study populations, mean age±SD at glaucoma diagnosis was 8.94±9.54 years and 50.4% were male. The most common gene discussed was CYP1B1, evaluated in 109 (55.6%) studies. CYP1B1 variants were associated with region and population-specific prevalence ranging from 5% to 86% among those with primary congenital glaucoma. MYOC variants were discussed in 31 (15.8%) studies with prevalence up to 36% among patients with juvenile open angle glaucoma. FOXC1 variants were discussed in 25 (12.8%) studies, which demonstrated phenotypic severity dependent on degree of gene expression and type of mutation. Overall risk of bias was low; the most common domains of bias were selection and comparability. Numerous genes and genetic changes have been associated with childhood glaucoma. Understanding the most common genes as well as potential genotype-phenotype correlation has the potential to improve diagnostic and prognostic outcomes for children with glaucoma.
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Affiliation(s)
- Anika Kumar
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
| | - Ying Han
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
| | - Julius T. Oatts
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
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3
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Carstens N, Goolam S, Hulley M, Brandenburg JT, Ramsay M, Williams SEI. Exome-based mutation screening in South African children with primary congenital glaucoma. Eye (Lond) 2023; 37:362-368. [PMID: 35094026 PMCID: PMC9873788 DOI: 10.1038/s41433-022-01941-7] [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: 03/24/2021] [Revised: 01/03/2022] [Accepted: 01/14/2022] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVES To identify pathogenic variants in a cohort of 23 black South African children with sporadic primary congenital glaucoma (PCG) using an exome-based approach. METHODS Children with PCG were recruited from two Paediatric Ophthalmology Clinics in Johannesburg, South Africa. Whole exome sequencing was performed on genomic DNA. Of the 23 children, 19 were male and 19 had bilateral PCG. A variant prioritization strategy was employed whereby variants in known PCG genes (CYP1B1, LTBP2 and TEK) were evaluated first, followed by the identification of putative disease-causing variants in other genes related to eye diseases and phenotypes. RESULTS Validated pathogenic variants in the CYP1B1 gene (c.1169 G>A; p.Arg390His) and TEK gene (c.922 G>A; p.Gly308Arg) were identified in one child each. No LTBP2 mutations were identified in this cohort. In silico predictions identified potentially damaging rare variants in genes previously associated with eye development phenotypes or glaucoma in a further 12 children. CONCLUSIONS This study demonstrates the value of whole exome sequencing in identifying disease-causing variants in African children with PCG. It is the first report of a TEK disease-causing variant in an African PCG patient. Potential causative variants detected in PCG candidate genes warrant further investigation.
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Affiliation(s)
- Nadia Carstens
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Saadiah Goolam
- Division of Ophthalmology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Michaella Hulley
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jean-Tristan Brandenburg
- Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Michele Ramsay
- Division of Human Genetics, National Health Laboratory Service and School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Sydney Brenner Institute for Molecular Bioscience, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Susan Eileen Isabella Williams
- Division of Ophthalmology, Department of Neurosciences, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Karaconji T, Zagora S, Grigg JR. Approach to childhood glaucoma: A review. Clin Exp Ophthalmol 2022; 50:232-246. [PMID: 35023613 DOI: 10.1111/ceo.14039] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/01/2021] [Accepted: 12/10/2021] [Indexed: 12/15/2022]
Abstract
Childhood glaucoma represents a heterogenous group of rare ocular conditions that may result in significant sight threatening complications related to elevated intraocular pressure (IOP). It can be classified as either primary or secondary and the latter may have systemic associations. This review will be based on the work of the childhood glaucoma research network (CGRN) and will focus on the diagnosis and management of the most common types of childhood glaucoma. These include primary congenital glaucoma (PCG) and juvenile open angle glaucoma (JOAG) as well as secondary causes of glaucoma associated with non-acquired ocular anomalies (Axenfeld-Rieger anomaly; Peters anomaly and Aniridia), glaucoma associated with systemic disease (Sturge Weber syndrome and Neurofibromatosis), those due to acquired conditions (Uveitic glaucoma, trauma and tumours) and importantly glaucoma following cataract surgery.
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Affiliation(s)
- Tanya Karaconji
- Speciality of Ophthalmology, Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.,Department of Ophthalmology, The Children's Hospital, Westmead, Australia
| | - Sophia Zagora
- Speciality of Ophthalmology, Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.,Department of Ophthalmology, The Children's Hospital, Westmead, Australia
| | - John R Grigg
- Speciality of Ophthalmology, Save Sight Institute, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.,Department of Ophthalmology, The Children's Hospital, Westmead, Australia.,Eye Genetics Research Group Children's Medical Research Institute, The Children's Hospital at Westmead and Eye Genetics Clinics, The Children's Hospital at Westmead, Westmead, Australia
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Calero-Dueñas N, Mateos-Olivares M, Ussa F, Juberías JR, Marcos M, Pastor-Idoate S, Usategui-Martín R. Polymorphisms in CYP1B1 gene and the risk of suffering Primary Open-Angle Glaucoma: Systematic review and meta-analysis. Eur J Ophthalmol 2022; 32:1841-1849. [PMID: 35138193 DOI: 10.1177/11206721221077621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE It had been reported that mutations in CYP1B1 gene probably play an important role in the pathogenesis of primary open angle glaucoma (POAG) but the existing genetic association studies show contradictory results. Thus, the objective of our study was to perform a systematic review and meta-analysis to characterize more precisely the potential association between given polymorphisms in CYP1B1 gene and the risk of suffering POAG. METHODS A systematic review of studies that related the risk of carrying CYP1B1 gene polymorphisms with POAG development was conducted. We selected 19 case-control studies including 3855 POAG patients and 4125 control subjects in our meta-analyses. A random effects model was used. Sensitivity analysis and assessment of bias were also included. RESULTS The prevalence of CYP1B1 gene polymorphisms were significantly more frequent among POAG patients compared to all controls (OR = 2.91, 95% CI = 1.37 - 6.21; P = 0.006). Moreover, their prevalence was significantly higher in juvenile-onset patients than in adult-onset ones (OR = 2.27, 95% CI = 1.20-4.28; P = 0.001). CONCLUSION The results of this meta-analysis uphold that being a carrier of polymorphic genetic variants in CYP1B1 gene would increase the risk of POAG, especially the juvenile onset.
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Affiliation(s)
| | - Milagros Mateos-Olivares
- Departament of Ophthalmology, 16238Hospital Universitario de Valladolid, Valladolid, Spain
- 537068Institute of Applied Ophthalmobiology (IOBA), University of Valladolid, Valladolid, Spain
| | - Fernando Ussa
- 537068Institute of Applied Ophthalmobiology (IOBA), University of Valladolid, Valladolid, Spain
- Department of Ophthalmology, 156705The James Cook University Hospital, Middlesbrough, UK
| | - José R Juberías
- Departament of Ophthalmology, 16238Hospital Universitario de Valladolid, Valladolid, Spain
- 537068Institute of Applied Ophthalmobiology (IOBA), University of Valladolid, Valladolid, Spain
| | - Miguel Marcos
- Department of Internal Medicine, University Hospital of Salamanca-IBSAL; 37479University of Salamanca, Salamanca, Spain
| | - Salvador Pastor-Idoate
- Departament of Ophthalmology, 16238Hospital Universitario de Valladolid, Valladolid, Spain
- 537068Institute of Applied Ophthalmobiology (IOBA), University of Valladolid, Valladolid, Spain
- Cooperative Health Network for Research in Ophthalmology (Oftared), National Institute of Health Carlos III, ISCIII, Madrid, Spain
| | - Ricardo Usategui-Martín
- 537068Institute of Applied Ophthalmobiology (IOBA), University of Valladolid, Valladolid, Spain
- Cooperative Health Network for Research in Ophthalmology (Oftared), National Institute of Health Carlos III, ISCIII, Madrid, Spain
- Department of Cell Biology, Histology and Pharmacology, Faculty of Medicine, University of Valladolid, Valladolid, Spain
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Knight LSW, Ruddle JB, Taranath DA, Goldberg I, Smith JEH, Gole G, Chiang MY, Willett F, D'Mellow G, Breen J, Qassim A, Mullany S, Elder JE, Vincent AL, Staffieri SE, Kearns LS, Mackey DA, Luu S, Siggs OM, Souzeau E, Craig JE. Childhood and Early Onset Glaucoma Classification and Genetic Profile in a Large Australasian Disease Registry. Ophthalmology 2021; 128:1549-1560. [PMID: 33892047 DOI: 10.1016/j.ophtha.2021.04.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/12/2021] [Accepted: 04/12/2021] [Indexed: 12/22/2022] Open
Abstract
PURPOSE To report the relative frequencies of childhood and early onset glaucoma subtypes and their genetic findings in a large single cohort. DESIGN Retrospective clinical and molecular study. PARTICIPANTS All individuals with childhood glaucoma (diagnosed 0 to <18 years) and early onset glaucoma (diagnosed 18 to <40 years) referred to a national disease registry. METHODS We retrospectively reviewed the referrals of all individuals with glaucoma diagnosed at <40 years of age recruited to the Australian and New Zealand Registry of Advanced Glaucoma (ANZRAG). Subtypes of glaucoma were determined using the Childhood Glaucoma Research Network (CGRN) classification system. DNA extracted from blood or saliva samples underwent sequencing of genes associated with glaucoma. MAIN OUTCOME MEASURES The phenotype and genotype distribution of glaucoma diagnosed at <40 years of age. RESULTS A total of 290 individuals (533 eyes) with childhood glaucoma and 370 individuals (686 eyes) with early onset glaucoma were referred to the ANZRAG. Primary glaucoma was the most prevalent condition in both cohorts. In the childhood cohort, 57.6% of individuals (167/290, 303 eyes) had primary congenital glaucoma (PCG), and 19.3% (56/290, 109 eyes) had juvenile open-angle glaucoma. Juvenile open-angle glaucoma constituted 73.2% of the early onset glaucoma cohort (271/370, 513 eyes). Genetic testing in probands resulted in a diagnostic yield of 24.7% (125/506) and a reclassification of glaucoma subtype in 10.4% of probands (13/125). The highest molecular diagnostic rate was achieved in probands with glaucoma associated with nonacquired ocular anomalies (56.5%). Biallelic variants in CYP1B1 (n = 29, 23.2%) and heterozygous variants in MYOC (n = 24, 19.2%) and FOXC1 (n = 21, 16.8%) were most commonly reported among probands with a molecular diagnosis. Biallelic CYP1B1 variants were reported in twice as many female individuals as male individuals with PCG (66.7% vs. 33.3%, P = 0.02). CONCLUSIONS We report on the largest cohort of individuals with childhood and early onset glaucoma from Australasia using the CGRN classification. Primary glaucoma was most prevalent. Genetic diagnoses ascertained in 24.7% of probands supported clinical diagnoses and genetic counseling. International collaborative efforts are required to identify further genes because the majority of individuals still lack a clear molecular diagnosis.
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Affiliation(s)
- Lachlan S W Knight
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia.
| | - Jonathan B Ruddle
- Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia; Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Deepa A Taranath
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Ivan Goldberg
- Discipline of Ophthalmology, Save Sight Institute, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
| | - James E H Smith
- Discipline of Ophthalmology, Save Sight Institute, Faculty of Medicine and Health, University of Sydney, Sydney, Australia; Department of Ophthalmology, The Children's Hospital at Westmead, Sydney, Australia; Department of Ophthalmology, Macquarie University Hospital, Sydney, Australia
| | - Glen Gole
- University of Queensland Children's Health Queensland Clinical Unit, Queensland Children's Hospital, Brisbane, Australia
| | - Mark Y Chiang
- Department of Ophthalmology, Queensland Children's Hospital, Brisbane, Australia
| | - Faren Willett
- Department of Ophthalmology, Queensland Children's Hospital, Brisbane, Australia
| | | | - James Breen
- South Australian Genomics Centre, South Australian Health & Medical Research Institute, Adelaide, Australia; Robinson Research Institute, University of Adelaide, Adelaide, Australia; Adelaide Medical School, University of Adelaide, Adelaide, Australia
| | - Ayub Qassim
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Sean Mullany
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - James E Elder
- Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Andrea L Vincent
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Science, University of Auckland, Auckland, New Zealand; Eye Department, Greenlane Clinical Centre, Auckland District Health Board, Auckland, New Zealand
| | - Sandra E Staffieri
- Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Lisa S Kearns
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - David A Mackey
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia; Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Lions Eye Institute, Centre for Vision Sciences, University of Western Australia, Perth, Australia; Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Susie Luu
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Owen M Siggs
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Emmanuelle Souzeau
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Jamie E Craig
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
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Souzeau E, Weisschuh N, Craig JE, Pasutto F, Koch KW. An Assessment of GUCA1C Variants in Primary Congenital Glaucoma. Genes (Basel) 2021; 12:genes12030359. [PMID: 33801495 PMCID: PMC7998521 DOI: 10.3390/genes12030359] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/16/2022] Open
Affiliation(s)
- Emmanuelle Souzeau
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Bedford Park, SA 5042, Australia;
- Correspondence: ; Tel.: +61-8-8204-5064
| | - Nicole Weisschuh
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, 72076 Tübingen, Germany;
| | - Jamie E. Craig
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Bedford Park, SA 5042, Australia;
| | - Francesca Pasutto
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany;
| | - Karl-Wilhelm Koch
- Department of Neuroscience, Division of Biochemistry, University of Oldenburg, 26129 Oldenburg, Germany;
- Research Center for Neurosensory Sciences, University of Oldenburg, 26129 Oldenburg, Germany
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8
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Jemmeih S, Malik S, Okashah S, Zayed H. Genetic Epidemiology of Primary Congenital Glaucoma in the 22 Arab Countries: A Systematic Review. Ophthalmic Epidemiol 2021; 29:1-12. [PMID: 33641569 DOI: 10.1080/09286586.2021.1883676] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE Primary congenital glaucoma (PCG) is a rare glaucoma type that develops in early infantile period and contributes to an elevated pressure on ocular cavity. Variants in CYP1B1 gene are the most encountered in PCG cases. The prevalence of PCG is relatively high among Arabs, however its genetic epidemiology remains understudied. This study aims to systematically identify all reported PCG disease-causing variants in the Arab population and investigate their potential genotype-phenotype correlations. METHODS We searched four different databases (PubMed, ScienceDirect, Google Scholar, and Scopus) from the time of inception until July 2020. Broad search terms were used to capture all possible information about the genetic epidemiology of PCG among Arabs. RESULTS We identified a total of 77 disease-causing variants in 361 patients and 88 families; of these, 33 were unique to Arabs. Sixty-nine variants were identified in the CYP1B1 gene, five variants were in the MYOC gene and single variants were reported in NTF4, FOXC1, and WDR36 genes. The most common reported variant was the c.182 G > A in the CYP1B1 gene. All identified variants were from ten Arab Countries (Saudi Arabia, Kuwait, Oman, Egypt, Morocco, Lebanon, Tunisia, Iraq, Algeria, and Mauritania). We identified 44 shared variants with other ethnicities demonstrated a distinctive genotype-phenotype correlation. Consanguinity was observed in the majority of Arab PCG patients, ranging from 45% to 100%. CONCLUSION PCG causing variants were identified in 10 Arab countries, which were mostly detected in the CYB1P1 gene. Arab patients with PCG seem to have distinctive genotype-phenotype correlations.
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Affiliation(s)
- Sara Jemmeih
- Department of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha. Qatar
| | - Shaza Malik
- Department of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha. Qatar
| | - Sarah Okashah
- Department of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha. Qatar
| | - Hatem Zayed
- Department of Biomedical Sciences, College of Health Sciences, QU Health, Qatar University, Doha. Qatar
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Ling C, Zhang D, Zhang J, Sun H, Du Q, Li X. Updates on the molecular genetics of primary congenital glaucoma (Review). Exp Ther Med 2020; 20:968-977. [PMID: 32742340 PMCID: PMC7388405 DOI: 10.3892/etm.2020.8767] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 04/01/2020] [Indexed: 12/14/2022] Open
Abstract
Primary congenital glaucoma (PCG) is one of the primary causes of blindness in children and is characterized by congenital trabecular meshwork and anterior chamber angle dysplasia. While being a rare condition, PCG severely impairs the quality of life of affected patients. However, the pathogenesis of PCG remains to be fully elucidated. It has previously been indicated that genetic factors serve a critical role in the pathogenesis of PCG, although patients with PCG exhibit significant genetic heterogeneity. Mutations in the cytochrome P450 family 1 subfamily B member 1 gene have been implicated in PCG and further genes that have been reported to be involved in PCG are myocilin, forkhead box C1, collagen type I α1 chain and latent transforming growth factor β binding protein 2. The present review aims to provide an up to date understanding of the genes associated with PCG and the use of molecular technologies in the identification of such genes and mutations. This may pave the way for the development of preventative methods, early diagnosis and improved therapeutic strategies in PCG.
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Affiliation(s)
- Chen Ling
- Sichuan Provincial Key Laboratory for Genetic Disease, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, P.R. China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610072, P.R. China
| | - Dingding Zhang
- Sichuan Provincial Key Laboratory for Genetic Disease, Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, P.R. China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, 610072, P.R. China
| | - Jing Zhang
- Department of Thoracic Surgery, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan 611731, P.R. China
| | - Huanxin Sun
- Department of Immunology, North Sichuan Medical College, Nanchong, Sichuan 637100, P.R. China
| | - Qiu Du
- College of Medical Technology, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610072, P.R. China
| | - Xuefei Li
- College of Medical Technology, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan 610072, P.R. China
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10
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Siggs OM, Souzeau E, Pasutto F, Dubowsky A, Smith JEH, Taranath D, Pater J, Rait JL, Narita A, Mauri L, Del Longo A, Reis A, Chappell A, Kearns LS, Staffieri SE, Elder JE, Ruddle JB, Hewitt AW, Burdon KP, Mackey DA, Craig JE. Prevalence of FOXC1 Variants in Individuals With a Suspected Diagnosis of Primary Congenital Glaucoma. JAMA Ophthalmol 2020; 137:348-355. [PMID: 30653210 DOI: 10.1001/jamaophthalmol.2018.5646] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance Both primary and secondary forms of childhood glaucoma have many distinct causative mechanisms, and in many cases a cause is not immediately clear. The broad phenotypic spectrum of secondary glaucoma, particularly in individuals with variants in FOXC1 or PITX2 genes associated with Axenfeld-Rieger syndrome, makes it more difficult to diagnose patients with milder phenotypes. These cases are occasionally classified and managed as primary congenital glaucoma. Objective To investigate the prevalence of FOXC1 variants in participants with a suspected diagnosis of primary congenital glaucoma. Design, Setting, and Participants Australian and Italian cohorts were recruited from January 1, 2007, through March 1, 2016. Australian individuals were recruited through the Australian and New Zealand Registry of Advanced Glaucoma and Italian individuals through the Genetic and Ophthalmology Unit of l'Azienda Socio-Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda in Milan, Italy. We performed exome sequencing, in combination with Sanger sequencing and multiplex ligation-dependent probe amplification, to detect variants of FOXC1 in individuals with a suspected diagnosis of primary congenital glaucoma established by their treating specialist. Data analysis was completed from June 2015 to November 2017. Main Outcome and Measures Identification of single-nucleotide and copy number variants in FOXC1, along with phenotypic characterization of the individuals who carried them. Results A total of 131 individuals with a suspected diagnosis of primary congenital glaucoma were included. The mean (SD) age at recruitment in the Australian cohort was 24.3 (18.1) years; 37 of 84 Australian participants (44.0%) were female, and 71 of 84 (84.5%) were of European ancestry. The mean (SD) age at recruitment was 22.5 (18.4) years in the Italian cohort; 21 of 47 Italian participants (44.7%) were female, and 45 of 47 (95.7%) were of European ancestry. We observed rare, predicted deleterious FOXC1 variants in 8 of 131 participants (6.1%), or 8 of 166 participants (4.8%) when including those explained by variants in CYP1B1. On reexamination or reinvestigation, all of these individuals had at least 1 detectable ocular and/or systemic feature associated with Axenfeld-Rieger syndrome. Conclusions and Relevance These data highlight the genetic and phenotypic heterogeneity of childhood glaucoma and support the use of gene panels incorporating FOXC1 as a diagnostic aid, especially because clinical features of Axenfeld-Rieger syndrome can be subtle. Further replication of these results will be needed to support the future use of such panels.
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Affiliation(s)
- Owen M Siggs
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Emmanuelle Souzeau
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Francesca Pasutto
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - James E H Smith
- Department of Ophthalmology, Children's Hospital at Westmead, Sydney, Australia.,Discipline of Ophthalmology, University of Sydney, Sydney, Australia.,Department of Ophthalmology, Macquarie University, Sydney, Australia
| | - Deepa Taranath
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - John Pater
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Julian L Rait
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia
| | | | - Lucia Mauri
- Medical Genetics Unit, Department of Laboratory Medicine, l'Azienda Socio-Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Alessandra Del Longo
- Pediatric Ophthalmology Unit, l'Azienda Socio-Sanitaria Territoriale Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - André Reis
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Angela Chappell
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
| | - Lisa S Kearns
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia
| | - Sandra E Staffieri
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia.,Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia
| | - James E Elder
- Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia.,Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Jonathan B Ruddle
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia.,Department of Ophthalmology, Royal Children's Hospital, Melbourne, Australia
| | - Alex W Hewitt
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Australia.,Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Kathryn P Burdon
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia.,Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - David A Mackey
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.,Centre for Ophthalmology and Visual Science and Lions Eye Institute, University of Western Australia, Perth, Australia
| | - Jamie E Craig
- Department of Ophthalmology, Flinders University, Flinders Medical Centre, Adelaide, Australia
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11
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Khafagy MM, El-Guendy N, Tantawy MA, Eldaly MA, Elhilali HM, Abdel Wahab AHA. Novel CYP1B1 mutations and a possible prognostic use for surgical management of congenital glaucoma. Int J Ophthalmol 2019; 12:607-614. [PMID: 31024815 DOI: 10.18240/ijo.2019.04.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 11/09/2018] [Indexed: 01/03/2023] Open
Abstract
AIM To identify CYP1B1 gene mutations and evaluate their possible role as a prognostic factor for success rates in the surgical management of Egyptian congenital glaucoma patients. METHODS Totally 42 eyes of 29 primary congenital glaucoma patients were operated on with combined trabeculotomy/trabeculectomy with mitomycin-C and followed up at 1d, 1wk, 1, 6 and 12mo postoperatively. Genomic DNA was extracted from peripheral blood leukocytes. Coding regions of CYP1B1 gene were amplified using 13 pairs of primers, screened for mutations using single-strand conformation polymorphism followed by sequencing of both strands. Efficacy of the operation was graded as either a success [maintaining intraocular pressure (IOP) less than 21 mm Hg with or without anti-glaucoma medication], or a failure (IOP more than 21 mm Hg with topical antiglaucoma medications). RESULTS Seven novel mutations out of a total of 15 different mutations were found in the CYP1B1 genes of 14 patients (48.2%). The presence of CYP1B1 gene mutations did not correlate with the failure of the surgery (P=0.156, odds ratio=3.611, 95%CI, 0.56 to 22.89); while the positive consanguinity strongly correlated with failure of the initial procedure (P=0.016, odds ratio=11.25, 95%CI, 1.57 to 80.30). However, the Kaplan-Meier survival analysis revealed a significantly lower time of IOP control in the subgroup with mutations in CYP1B1 versus the congenital primary glaucoma group without mutations (log rank test, P=0.015). CONCLUSION Seven new CYP1B1 mutations are identified in Egyptian patients. Patients harboring confirmed mutations suffered from early failure of the initial surgery. CYP1B1 mutations could be considered as a prognostic factor for surgery in primary congenital glaucoma.
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Affiliation(s)
- Mohamed M Khafagy
- Ophthalmology Department, Faculty of Medicine, Cairo University, Cairo 11562, Egypt
| | - Nadia El-Guendy
- Cancer Biology Department, National Cancer Institute, Cairo University, Cairo 11796, Egypt
| | - Marwa A Tantawy
- Research Department, Children's Cancer Hospital, Cairo 11617, Egypt
| | - Mohamed A Eldaly
- Ophthalmology Department, Faculty of Medicine, Cairo University, Cairo 11562, Egypt
| | - Hala M Elhilali
- Ophthalmology Department, Faculty of Medicine, Cairo University, Cairo 11562, Egypt
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12
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Gupta V, Somarajan BI, Walia GK, Kaur J, Kumar S, Gupta S, Chaurasia AK, Gupta D, Kaushik A, Mehta A, Gupta V, Sharma A. Role of CYP1B1, p.E229K and p.R368H mutations among 120 families with sporadic juvenile onset open-angle glaucoma. Graefes Arch Clin Exp Ophthalmol 2017; 256:355-362. [PMID: 29168043 DOI: 10.1007/s00417-017-3853-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 11/06/2017] [Accepted: 11/13/2017] [Indexed: 12/01/2022] Open
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13
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Angiopoietin receptor TEK interacts with CYP1B1 in primary congenital glaucoma. Hum Genet 2017; 136:941-949. [PMID: 28620713 DOI: 10.1007/s00439-017-1823-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/12/2017] [Indexed: 10/19/2022]
Abstract
Primary congenital glaucoma (PCG) is a severe autosomal recessive ocular disorder associated with considerable clinical and genetic heterogeneity. Recently, rare heterozygous alleles in the angiopoietin receptor-encoding gene TEK were implicated in PCG. We undertook this study to ascertain the second mutant allele in a large cohort (n = 337) of autosomal recessive PCG cases that carried heterozygous TEK mutations. Our investigations revealed 12 rare heterozygous missense mutations in TEK by targeted sequencing. Interestingly, four of these TEK mutations (p.E103D, p.I148T, p.Q214P, and p.G743A) co-occurred with three heterozygous mutations in another major PCG gene CYP1B1 (p.A115P, p.E229K, and p.R368H) in five families. The parents of these probands harbored either of the heterozygous TEK or CYP1B1 alleles and were asymptomatic, indicating a potential digenic mode of inheritance. Furthermore, we ascertained the interactions of TEK and CYP1B1 by co-transfection and pull-down assays in HEK293 cells. Ligand responsiveness of the wild-type and mutant TEK proteins was assessed in HUVECs using immunofluorescence analysis. We observed that recombinant TEK and CYP1B1 proteins interact with each other, while the disease-associated allelic combinations of TEK (p.E103D)::CYP1B1 (p.A115P), TEK (p.Q214P)::CYP1B1 (p.E229K), and TEK (p.I148T)::CYP1B1 (p.R368H) exhibit perturbed interaction. The mutations also diminished the ability of TEK to respond to ligand stimulation, indicating perturbed TEK signaling. Overall, our data suggest that interaction of TEK and CYP1B1 contributes to PCG pathogenesis and argue that TEK-CYP1B1 may perform overlapping as well as distinct functions in manifesting the disease etiology.
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14
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García-Antón MT, Salazar JJ, de Hoz R, Rojas B, Ramírez AI, Triviño A, Aroca-Aguilar JD, García-Feijoo J, Escribano J, Ramírez JM. Goniodysgenesis variability and activity of CYP1B1 genotypes in primary congenital glaucoma. PLoS One 2017; 12:e0176386. [PMID: 28448622 PMCID: PMC5407778 DOI: 10.1371/journal.pone.0176386] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 04/10/2017] [Indexed: 11/19/2022] Open
Abstract
Mutations in the CYP1B1 gene are currently the main known genetic cause of primary congenital glaucoma (PCG), a leading cause of blindness in children. Here, we analyze for the first time the CYP1B1 genotype activity and the microscopic and clinical phenotypes in human PCG. Surgical pieces from trabeculectomy from patients with PCG (n = 5) and sclerocorneal rims (n = 3) from cadaver donors were processed for transmission electron microscopy. Patients were classified into three groups depending on goniodysgenesis severity, which was influenced by CYP1B1 enzymatic activity. The main histological changes observed in the outflow pathway of patients with PCG and mutations in CYP1B1 were: i) underdeveloped collector channels and the Schlemm’s canal; ii) abnormal insertion of the ciliary muscle; iii) death of the trabecular endothelial cells. Our findings could be useful in improving treatment strategy of PCG associated with CYP1B1 mutations.
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Affiliation(s)
- María T. García-Antón
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
| | - Juan J. Salazar
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Óptica y Optometría, Universidad Complutense de Madrid, Madrid, Spain
| | - Rosa de Hoz
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Óptica y Optometría, Universidad Complutense de Madrid, Madrid, Spain
| | - Blanca Rojas
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Ana I. Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Óptica y Optometría, Universidad Complutense de Madrid, Madrid, Spain
| | - Alberto Triviño
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - José-Daniel Aroca-Aguilar
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Área de Genética, Facultad de Medicina/Instituto de Investigación en Discapacidades Neurológicas (IDINE), Universidad de Castilla-La Mancha, Albacete, Spain
| | - Julián García-Feijoo
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Servicio de Oftalmología, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - Julio Escribano
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Área de Genética, Facultad de Medicina/Instituto de Investigación en Discapacidades Neurológicas (IDINE), Universidad de Castilla-La Mancha, Albacete, Spain
| | - José M. Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Universidad Complutense de Madrid, Madrid, Spain
- Cooperative Research Network on Age-Related Ocular Pathology, Visual and Life Quality, Instituto de Salud Carlos III, Madrid, Spain
- Departamento de Oftalmología y ORL, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
- * E-mail:
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15
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Yang Y, Zhang L, Li S, Zhu X, Sundaresan P. Candidate Gene Analysis Identifies Mutations in CYP1B1 and LTBP2 in Indian Families with Primary Congenital Glaucoma. Genet Test Mol Biomarkers 2017; 21:252-258. [PMID: 28384041 DOI: 10.1089/gtmb.2016.0203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Primary congenital glaucoma (PCG) is a severe ocular disorder that presents early in life. Cytochrome P4501B1 (CYP1B1) and latent transforming growth factor-beta-binding protein 2 (LTBP2) are the most commonly mutated genes in PCG. AIM To investigate the causative genetic mutations in eight Indian families with PCG. MATERIALS AND METHODS Whole-exome sequencing was applied to analyze the genomic DNA samples from PCG probands. Sanger sequencing was utilized to confirm the identified mutations. RESULTS We identified four homozygous missense mutations (c.1405C>T, p.R469W; c.1397G>T, p.G466V; c.1198C>T, p.P400S; and c.1103G>A, p.R368H) in CYP1B1 and one nonsense mutation (c.2421G>A, p.W807X) in LTBP2 in eight Indian families. Among the five mutations identified, G466V in CYP1B1 and W807X in LTBP2 represent novel mutations. CONCLUSIONS Our study expands the mutational spectrum of PCG in the Indian population.
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Affiliation(s)
- Yeming Yang
- 1 Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China , Chengdu, China .,2 Department of Clinical Laboratory, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, China .,3 Institue Of Laboratory Animal Sciences, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, Sichuan, China .,4 Key Laboratory for NeuroInformation of Ministry of Education and Medicine Information Center, University of Electronic Science and Technology of China , Chengdu, Sichuan, China
| | - Lin Zhang
- 1 Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China , Chengdu, China .,2 Department of Clinical Laboratory, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, China .,4 Key Laboratory for NeuroInformation of Ministry of Education and Medicine Information Center, University of Electronic Science and Technology of China , Chengdu, Sichuan, China
| | - Shujin Li
- 1 Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China , Chengdu, China .,2 Department of Clinical Laboratory, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, China .,5 Institute of Chengdu Biology, Sichuan Translational Medicine Hospital , Chinese Academy of Sciences, Chengdu, China
| | - Xianjun Zhu
- 1 Sichuan Provincial Key Laboratory for Human Disease Gene Study, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China , Chengdu, China .,2 Department of Clinical Laboratory, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, China .,3 Institue Of Laboratory Animal Sciences, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital , Chengdu, Sichuan, China .,4 Key Laboratory for NeuroInformation of Ministry of Education and Medicine Information Center, University of Electronic Science and Technology of China , Chengdu, Sichuan, China .,5 Institute of Chengdu Biology, Sichuan Translational Medicine Hospital , Chinese Academy of Sciences, Chengdu, China
| | - Periasamy Sundaresan
- 6 Department of Genetics, Aravind Medical Research Foundation, Aravind Eye Hospital , Madurai, Tamilnadu, India
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16
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17
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de Melo MB, Mandal AK, Tavares IM, Ali MH, Kabra M, de Vasconcellos JPC, Senthil S, Sallum JMF, Kaur I, Betinjane AJ, Moura CR, Paula JS, Costa KA, Sarfarazi M, Paolera MD, Finzi S, Ferraz VEF, Costa VP, Belfort R, Chakrabarti S. Genotype-Phenotype Correlations in CYP1B1-Associated Primary Congenital Glaucoma Patients Representing Two Large Cohorts from India and Brazil. PLoS One 2015; 10:e0127147. [PMID: 25978063 PMCID: PMC4433271 DOI: 10.1371/journal.pone.0127147] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/13/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Primary congenital glaucoma (PCG), occurs due to the developmental defects in the trabecular meshwork and anterior chamber angle in children. PCG exhibits genetic heterogeneity and the CYP1B1 gene has been widely implicated worldwide. Despite the diverse mutation spectra, the clinical implications of these mutations are yet unclear. The present study attempted to delineate the clinical profile of PCG in the background of CYP1B1 mutations from a large cohort of 901 subjects from India (n=601) and Brazil (n=300). METHODS Genotype-phenotype correlations was undertaken on clinically well characterized PCG cases from India (n=301) and Brazil (n=150) to assess the contributions of CYP1B1 mutation on a set of demographic and clinical parameters. The demographic (gender, and history of consanguinity) and quantitative clinical (presenting intraocular pressure [IOP] and corneal diameter [CD]) parameters were considered as binary and continuous variables, respectively, for PCG patients in the background of the overall mutation spectra and also with respect to the prevalent mutations in India (R368H) and Brazil (4340delG). All these variables were fitted in a multivariate logistic regression model using the Akaike Information Criterion (AIC) to estimate the adjusted odds ratio (OR) using the R software (version 2.14.1). RESULTS The overall mutation spectrum were similar across the Indian and Brazilian PCG cases, despite significantly higher number of homozygous mutations in the former (p=0.024) and compound heterozygous mutations in the later (p=0.012). A wide allelic heterogeneity was observed and only 6 mutations were infrequently shared between these two populations. The adjusted ORs for the binary (demographic) and continuous (clinical) variables did not indicate any susceptibility to the observed mutations (p>0.05). CONCLUSIONS The present study demonstrated a lack of genotype-phenotype correlation of the demographic and clinical traits to CYP1B1 mutations in PCG at presentation. However, the susceptibility of these mutations to the long-term progression of these traits are yet to be deciphered.
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Affiliation(s)
- Mônica Barbosa de Melo
- Center of Molecular Biology and Genetic Engineering, University of Campinas, Campinas, SP, Brazil
| | - Anil K. Mandal
- Jasti V Ramanamma Childrens Eye Care Centre, L.V. Prasad Eye Institute, Hyderabad, India
| | - Ivan M. Tavares
- Department of Ophthalmology, Federal University of São Paulo, SP, Brazil
| | - Mohammed Hasnat Ali
- Centre for Clinical Epidemiology and Biostatistics, L.V. Prasad Eye Institute, Hyderabad, India
| | - Meha Kabra
- Kallam Anji Reddy Molecular Genetics Laboratory, L.V. Prasad Eye Institute, Hyderabad, India
| | | | - Sirisha Senthil
- Jasti V Ramanamma Childrens Eye Care Centre, L.V. Prasad Eye Institute, Hyderabad, India
| | | | - Inderjeet Kaur
- Kallam Anji Reddy Molecular Genetics Laboratory, L.V. Prasad Eye Institute, Hyderabad, India
| | - Alberto J. Betinjane
- Department of Ophthalmology, University of São Paulo School of Medicine, São Paulo, SP, Brazil
| | | | - Jayter S. Paula
- Department of Ophthalmology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Karita A. Costa
- Department of Ophthalmology, Federal University of São Paulo, SP, Brazil
| | - Mansoor Sarfarazi
- Molecular Ophthalmic Genetics Laboratory, Surgical Research Center, Department of Surgery, University of Connecticut Health Center, Farmington, Connecticut, United States of America
| | - Mauricio Della Paolera
- Department of Ophthalmology, Irmandade da Santa Casa de Misericordia de São Paulo, School of Medical Sciences, São Paulo, SP, Brazil
| | - Simone Finzi
- Department of Ophthalmology, University of São Paulo School of Medicine, São Paulo, SP, Brazil
| | - Victor E. F. Ferraz
- Genetics Department, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Vital P. Costa
- Department of Ophthalmology, Faculty of Medical Sciences, University of Campinas, Campinas, SP, Brazil
| | - Rubens Belfort
- Department of Ophthalmology, Federal University of São Paulo, SP, Brazil
| | - Subhabrata Chakrabarti
- Kallam Anji Reddy Molecular Genetics Laboratory, L.V. Prasad Eye Institute, Hyderabad, India
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18
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Rudkin AK. Of gypsies and gene flows: CYP1B1. Clin Exp Ophthalmol 2015; 43:3-4. [DOI: 10.1111/ceo.12494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Adam K Rudkin
- South Australian Institute of Ophthalmology; Adelaide South Australia Australia
- Discipline of Ophthalmology and Visual Sciences; University of Adelaide; Adelaide South Australia Australia
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19
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Bouyacoub Y, Ben Yahia S, Abroug N, Kahloun R, Kefi R, Khairallah M, Abdelhak S. CYP1B1Gene Mutations Causing Primary Congenital Glaucoma in Tunisia. Ann Hum Genet 2014; 78:255-63. [DOI: 10.1111/ahg.12069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 04/15/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Yosra Bouyacoub
- Université Tunis El Manar; Institut Pasteur de Tunis, LR11IPT05; Biomedical Genomics and Oncogenetics Laboratory; 1002 Tunis Tunisia
- Université de Monastir; Institut Supérieur de Biotechnologie; Monastir 5000 Tunisia
| | - Salim Ben Yahia
- Université de Monastir; Faculty of Medicine; Fattouma Bourguiba University Hospital; Department of Ophthalmology; 5000 Monastir Tunisia
| | - Nesrine Abroug
- Université de Monastir; Faculty of Medicine; Fattouma Bourguiba University Hospital; Department of Ophthalmology; 5000 Monastir Tunisia
| | - Rim Kahloun
- Université de Monastir; Faculty of Medicine; Fattouma Bourguiba University Hospital; Department of Ophthalmology; 5000 Monastir Tunisia
| | - Rym Kefi
- Université Tunis El Manar; Institut Pasteur de Tunis, LR11IPT05; Biomedical Genomics and Oncogenetics Laboratory; 1002 Tunis Tunisia
| | - Moncef Khairallah
- Université de Monastir; Faculty of Medicine; Fattouma Bourguiba University Hospital; Department of Ophthalmology; 5000 Monastir Tunisia
| | - Sonia Abdelhak
- Université Tunis El Manar; Institut Pasteur de Tunis, LR11IPT05; Biomedical Genomics and Oncogenetics Laboratory; 1002 Tunis Tunisia
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20
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Faiq M, Sharma R, Dada R, Mohanty K, Saluja D, Dada T. Genetic, Biochemical and Clinical Insights into Primary Congenital Glaucoma. J Curr Glaucoma Pract 2013; 7:66-84. [PMID: 26997785 PMCID: PMC4741182 DOI: 10.5005/jp-journals-10008-1140] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Accepted: 04/09/2013] [Indexed: 12/21/2022] Open
Abstract
Glaucoma is an irreversible form of optic neuropathy in which the optic nerve suffers damage in a characteristic manner with optic nerve cupping and retinal ganglion cell death. Primary congenital glaucoma (PCG) is an idiopathic irreversible childhood blinding disorder which manifests at birth or within the first year of life. PCG presents with a classical triad of symptoms (viz epiphora, photophobia and blepharospasm) though there are many additional symptoms, including large eye ball and hazy cornea. The only anatomical anomaly found in PCG is trabecular meshwork (TM) dysgenesis. PCG is an inheritable disease with established genetic etiology. It transmits through autosomal recessive mode. A number of cases are sporadic also. Mutations in many genes have been found to be causative in PCG and many are yet to be found. Mutations in cytochrome P4501B1 (CYP1B1) gene have been found to be the predominant cause of PCG. Other genes that have been implicated in PCG etiology are myocilin, Forkhead-related transcription factor C1 (FOXC1) and latent transforming growth factor beta-binding protein 2 (LTBP2). Mutations in these genes have been reported from many parts of the world. In addition to this, mitochondrial genome mutations are also thought to be involved in its pathogenesis. There appears to be some mechanism involving more than one genetic factor. In this review, we will discuss the various clinical, biochemical and genetic aspects of PCG. We emphasize that etiology of PCG does not lie in a single gene or genetic factor. Research needs to be oriented into a direction where gene-gene interactions, ocular embryology, ophthalmic metabolism and systemic oxidative status need to be studied in order to understand this disorder. We also accentuate the need for ophthalmic genetic facilities in all ophthalmology setups. How to cite this article: Faiq M, Sharma R, Dada R, Mohanty K, Saluja D, Dada T. Genetic, Biochemical and Clinical Insights into Primary Congenital Glaucoma. J Current Glau Prac 2013;7(2):66-84.
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Affiliation(s)
- Muneeb Faiq
- Pursuing Doctorate, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Reetika Sharma
- Resident, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Rima Dada
- Additional Professor, Department of Anatomy, Laboratory for Molecular Reproduction and Genetics, All India Institute of Medical Sciences, New Delhi, India
| | - Kuldeep Mohanty
- Pursuing Doctorate, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Daman Saluja
- Professor, Medical Biotechnology Laboratory, Dr BR Ambedkar Centre for Biomedical Research, University of Delhi, New Delhi, India
| | - Tanuj Dada
- Additional Professor, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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Lim SH, Tran-Viet KN, Yanovitch TL, Freedman SF, Klemm T, Call W, Powell C, Ravichandran A, Metlapally R, Nading EB, Rozen S, Young TL. CYP1B1, MYOC, and LTBP2 mutations in primary congenital glaucoma patients in the United States. Am J Ophthalmol 2013; 155:508-517.e5. [PMID: 23218701 DOI: 10.1016/j.ajo.2012.09.012] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 09/11/2012] [Accepted: 09/12/2012] [Indexed: 01/07/2023]
Abstract
PURPOSE To screen primary congenital glaucoma patients in the United States for sequence variants within the CYP1B1, LTBP2, and MYOC genes using Sanger and whole exome sequencing. DESIGN Retrospective case-control study. METHODS Fifty-seven primary congenital glaucoma patients (47 families), 71 unaffected family members of the primary congenital glaucoma probands, and 101 healthy unrelated individuals were recruited from a single institution. Sanger sequencing of the primary congenital glaucoma gene, CYP1B1, was performed on 47 proband deoxyribonucleic acid samples. Simultaneously, whole exome sequencing was conducted on 3 families, each including more than 1 affected individual. Concurrently, 33 of 47 primary congenital glaucoma probands with extended family deoxyribonucleic acid samples were screened for LTBP2 and MYOC gene mutations. Exome-sequenced variations were validated by additional Sanger sequencing to confirm segregation of filtered disease-causing single nucleotide variations. RESULTS Seven primary congenital glaucoma families (14.9%) manifested disease phenotypes attributable to CYP1B1 mutations. One primary congenital glaucoma family possessed homozygous mutant alleles, whereas 6 families carried compound heterozygous mutations. Five novel combinations of compound heterozygous mutations were identified, of which 2 combinations were found with whole exome sequencing. No disease-causing mutations within the LTBP2 and MYOC genes were discovered. CONCLUSIONS This study analyzed CYP1B1, LTBP2, and MYOC mutations in a cohort of primary congenital glaucoma patients from the United States, applying whole exome sequencing as a complementary tool to Sanger sequencing. Whole exome sequencing, coupled with Sanger sequencing, may identify novel genes in primary congenital glaucoma patients who have no mutations in known primary congenital glaucoma genes.
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Null CYP1B1 genotypes in primary congenital and nondominant juvenile glaucoma. Ophthalmology 2012; 120:716-23. [PMID: 23218183 DOI: 10.1016/j.ophtha.2012.09.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2012] [Revised: 09/07/2012] [Accepted: 09/10/2012] [Indexed: 01/23/2023] Open
Abstract
PURPOSE To assess the mutation spectrum, enzymatic activity, and phenotypic features associated with CYP1B1 genotypes in primary congenital glaucoma (PCG) and nondominant juvenile glaucoma (ndJG). DESIGN CYP1B1 genotyping, segregation analysis, and functional evaluation of mutations in a cohort of patients. PARTICIPANTS A total of 177 probands clinically diagnosed with PCG (161) or ndJG (16). METHODS Automatic DNA sequencing of the promoter (-1 to -867) and the 3 CYP1B1 exons. CYP1B1 enzymatic activity was evaluated using an ethoxyresorufin O-deethylation assay in transfected HEK-293T cells. MAIN OUTCOME MEASURES Screening and functional evaluation of CYP1B1 mutations. Glaucoma diagnosis based on slit-lamp examination, measurement of intraocular pressure, gonioscopy, and fundus examination. RESULTS Thirty-one different mutations were identified in 56 PCG and 7 ndJG index cases. To the best of our knowledge, 3 of the identified mutations were novel (-337G>T, F123L, and I399_P400del). Approximately 56% of all mutation carriers were compound heterozygotes, 25% were homozygotes, and both groups inherited glaucoma as an autosomal recessive trait. Nineteen percent of carriers were heterozygotes and showed non-Mendelian segregation. In vitro and inferred functional analysis showed that no less than approximately 74% of the recessive genotypes result in null enzymatic activity. We detected variable expressivity in relation to age of onset and a possible case of incomplete penetrance in 3 of 6 families (50%), with more than 1 affected child or more than 1 subject carrying 2 CYP1B1 mutant alleles. Altogether, these data support that PCG is not a simple monogenic disease. In addition, most patients with PCG carrying null or putative null genotypes showed severe bilateral phenotypes featured by early disease onset, frequently at birth. The mean number of trabeculectomies per eye was significantly higher in carriers than in noncarriers. CONCLUSIONS This is the largest analysis of CYP1B1 mutations performed in European patients with PCG to date. Our data show that null CYP1B1 genotypes, and therefore complete absence of CYP1B1 activity, frequently lead to severe phenotypes. Our results support that CYP1B1 glaucoma is not a simple monogenic disease and that CYP1B1 activity levels could influence the phenotype.
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Overview of Cytochrome P450 1B1 gene mutations in patients with primary congenital glaucoma. Exp Eye Res 2011; 93:572-9. [DOI: 10.1016/j.exer.2011.07.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Revised: 07/10/2011] [Accepted: 07/21/2011] [Indexed: 11/19/2022]
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Kaur K, Mandal AK, Chakrabarti S. Primary Congenital Glaucoma and the Involvement of CYP1B1. Middle East Afr J Ophthalmol 2011; 18:7-16. [PMID: 21572728 PMCID: PMC3085158 DOI: 10.4103/0974-9233.75878] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Primary congenital glaucoma (PCG) is an autosomal recessive disorder in children due to the abnormal development of the trabecular meshwork and the anterior chamber angle. With an onset at birth to early infancy, PCG is highly prevalent in inbred populations and consanguinity is strongly associated with the disease. Gene mapping of PCG-affected families has identified three chromosomal loci, GLC3A, GLC3B and GLC3C, of which, the CYP1B1 gene on GLC3A harbors mutations in PCG. The mutation spectra of CYP1B1 vary widely across different populations but are well structured based on geographic and haplotype backgrounds. Structural and functional studies on CYP1B1 have suggested its potential role in the development and onset of glaucomatous symptoms. A new locus (GLC3D) harboring the LTBP2 gene has been characterized in developmental glaucoma but its role in classical cases of PCG is yet to be understood. In this review, we provide insight into PCG pathogenesis and the potential role of CYP1B1 in the disease phenotype.
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Affiliation(s)
- Kiranpreet Kaur
- Kallam Anji Reddy Molecular Genetics Laboratory, Prof. Brien Holden Eye Research Centre, L.V. Prasad Eye Institute, Hyderabad, India
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Azmanov DN, Dimitrova S, Florez L, Cherninkova S, Draganov D, Morar B, Saat R, Juan M, Arostegui JI, Ganguly S, Soodyall H, Chakrabarti S, Padh H, López-Nevot MA, Chernodrinska V, Anguelov B, Majumder P, Angelova L, Kaneva R, Mackey DA, Tournev I, Kalaydjieva L. LTBP2 and CYP1B1 mutations and associated ocular phenotypes in the Roma/Gypsy founder population. Eur J Hum Genet 2011; 19:326-33. [PMID: 21081970 PMCID: PMC3062003 DOI: 10.1038/ejhg.2010.181] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 09/28/2010] [Accepted: 10/08/2010] [Indexed: 12/19/2022] Open
Abstract
Primary congenital glaucoma (PCG) is a genetically heterogeneous autosomal recessive disorder, which is an important cause of blindness in childhood. The first known gene, CYP1B1, accounts for a variable proportion of cases in most populations. A second gene, LTBP2, was recently reported in association with a syndrome, in which glaucoma is secondary to lens dislocation. We report on the molecular and clinical profile of 34 families diagnosed as PCG, all originating from the Roma/Gypsy founder population. Comprehensive sequencing analysis revealed a level of heterogeneity unusual for this population, with five CYP1B1 and one ancestral LTBP2 mutation accounting for ∼70% of patients (25 out of 37) and the remainder still unexplained. Homozygosity for the founder LTBP2 p.R299X mutation resulted in a more severe clinical phenotype and poorer outcome despite a markedly higher number of surgical interventions. The genetically homogeneous group of p.R299X homozygotes showed variable phenotypes (presumably also underlying pathogenetic mechanisms), wherein PCG proper with primary dysgenesis of the trabecular meshwork, and Marfan syndrome-like zonular disease with ectopia lentis and later onset secondary glaucoma are two extremes. The spectrum manifestations may occur in different combinations and have a different evolution even within the same sibship or a single patient. Preliminary observations on compounds with mutations in both CYP1B1-LTBP2 suggest that the observed combinations are of no clinical significance and digenic inheritance is unlikely. We provide a population genetics perspective to explain the allelic heterogeneity, comparing the history and geographic distribution of the two major founder mutations--p.R299X/LTBP2 and p.E387K/CYP1B1.
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Affiliation(s)
- Dimitar N Azmanov
- Laboratory for Molecular Genetics, Centre for Medical Research and Western Australian Institute for Medical Research, QEII Medical Centre, University of Western Australia, Perth, Western Australia, Australia
| | | | - Laura Florez
- Laboratory for Molecular Genetics, Centre for Medical Research and Western Australian Institute for Medical Research, QEII Medical Centre, University of Western Australia, Perth, Western Australia, Australia
| | | | | | - Bharti Morar
- Laboratory for Molecular Genetics, Centre for Medical Research and Western Australian Institute for Medical Research, QEII Medical Centre, University of Western Australia, Perth, Western Australia, Australia
| | - Rosmawati Saat
- Laboratory for Molecular Genetics, Centre for Medical Research and Western Australian Institute for Medical Research, QEII Medical Centre, University of Western Australia, Perth, Western Australia, Australia
| | - Manel Juan
- Servei d'Immunologia, IDIBAPS-Hospital Clínic, Barcelona, Spain
| | | | - Sriparna Ganguly
- Human Genetics Unit, Indian Statistical Institute, Kolkata, India
| | - Himla Soodyall
- National Health Laboratory Service, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Harish Padh
- BV Patel Pharmaceutical Education and Research Development Centre, Thaltej, Ahmedabad, India
| | - Miguel A López-Nevot
- Servicio de Análisis Clínicos, Hospital Universitario Virgen de las Nieves, Universidad de Granada, Granada, Spain
| | | | - Botio Anguelov
- Department of Ophthalmology, Medical University, Sofia, Bulgaria
| | - Partha Majumder
- Human Genetics Unit, Indian Statistical Institute, Kolkata, India
- National Institute of Biomedical Genomics, Kalyani, India
| | - Lyudmila Angelova
- Department of Paediatrics and Medical Genetics, Medical University, Varna, Bulgaria
| | - Radka Kaneva
- Molecular Medicine Centre, Medical University, Sofia, Bulgaria
| | - David A Mackey
- Lions Eye Institute, University of Western Australia, Perth, Western Australia, Australia
| | - Ivailo Tournev
- Department of Neurology, Medical University, Sofia, Bulgaria
- Department of Cognitive Science and Psychology, New Bulgarian University, Sofia, Bulgaria
| | - Luba Kalaydjieva
- Laboratory for Molecular Genetics, Centre for Medical Research and Western Australian Institute for Medical Research, QEII Medical Centre, University of Western Australia, Perth, Western Australia, Australia
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López-Garrido MP, Campos-Mollo E, Harto MA, Escribano J. Primary congenital glaucoma caused by the homozygous F261L CYP1B1 mutation and paternal isodisomy of chromosome 2. Clin Genet 2009; 76:552-7. [PMID: 19807744 DOI: 10.1111/j.1399-0004.2009.01242.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Primary congenital glaucoma (PCG), a rare, severe and blinding disease, usually results from mutations in the CYP1B1 gene located in chromosome 2p22.2. Uniparental isodisomy (UPID) is also a rare condition in which a diploid offspring carries two identical copies of a single parental chromosome. By DNA sequence analysis, we found that a proband (female newborn) affected by PCG was homozygous for the null-allele F261L of the CYP1B1 gene. Her father was a heterozygous carrier for this mutation, and unexpectedly her mother carried only the G168D mutation in the heterozygous state. Segregation analysis of eight microsatellite markers which spanned the two arms of chromosome 2 was consistent with paternal isodisomy for this chromosome in the proband. To the best of our knowledge, this is the first reported case of UPID resulting in PCG and the fifth reported case of paternal UPID for chromosome 2. In addition, the absence of a clinical phenotype other than PCG confirms previous observations of there being no paternally imprinted genes in chromosome 2 that have major phenotypic effects. These results, along with previous reports, also suggest that UPID may play a relevant role in recessive diseases linked to chromosome 2.
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Affiliation(s)
- M-P López-Garrido
- Area de Genética, Facultad de Medicina/Centro Regional de Investigaciones Biomédicas (CRIB), Universidad de Castilla-La Mancha, 02006 Albacete, Spain
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Weisschuh N, Wolf C, Wissinger B, Gramer E. A clinical and molecular genetic study of German patients with primary congenital glaucoma. Am J Ophthalmol 2009; 147:744-53. [PMID: 19195637 DOI: 10.1016/j.ajo.2008.11.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 11/10/2008] [Accepted: 11/13/2008] [Indexed: 11/19/2022]
Abstract
PURPOSE To estimate an accurate incidence rate for CYP1B1 mutations in German patients with primary congenital glaucoma (PCG). DESIGN Observational case series. METHODS Blood was obtained from 39 unrelated patients of German origin with clear clinical features of PCG and screened for mutations in the CYP1B1 gene using direct deoxyribonucleic acid sequencing. One hundred ethnically matched control subjects were screened for novel sequence variants using restriction fragment length polymorphism and denaturing high-performance liquid chromatography. RESULTS Sequence analysis identified 11 different mutations in 7 patients (18%). Four patients were compound heterozygotes, 2 subjects heterozygous, and 1 homozygous for CYP1B1 mutations. One deletion (c.199_206del8) and 3 missense mutations (L177P, F190L, and S282N) were novel. None of the novel missense mutations identified was found in normal controls. CONCLUSIONS Our results indicate that only a minor proportion of German PCG patients harbor mutations in the CYP1B1 gene and are in line with similar studies from other ethnic populations in which the rate of consanguinity is low. In addition, this is the first report discussing the phenotypes of German PCG patients with and without CYP1B1 mutations.
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Affiliation(s)
- Nicole Weisschuh
- Centre for Ophthalmology, Institute for Ophthalmic Research, Molecular Genetics Laboratory, Tuebingen, Germany.
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Characterization of the biochemical and structural phenotypes of four CYP1B1 mutations observed in individuals with primary congenital glaucoma. Pharmacogenet Genomics 2008; 18:665-76. [PMID: 18622259 DOI: 10.1097/fpc.0b013e3282ff5a36] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective of this study was to examine the biochemical and physical properties of cytochrome P450 1B1 (CYP1B1) mutants, test our hypothesis that primary congenital glaucoma (PCG)-causing mutants have altered metabolic activity, and correlate these to structural changes in the molecule. METHODS CYP1B1.1 cDNA was mutated to four forms found in individuals with the PCG phenotype, Y81N, E229K, A330F, and R368H. Expression and stability of the mutant hemoproteins and their ability to metabolize beta-estradiol, arachidonic acid, and retinoids, were determined. Alterations in mutant properties were related to structural changes by in silico examination, on the basis of the CYP1A2 crystal structure. RESULTS CYP1B1 mutations strongly affected the stability, ease of heterologous expression, and enzymatic properties of the protein. These were related to the location of the amino acid substitutions in the CYP1B1 structure. Three of the mutations involve residues located on the surface of CYP1B1, Y81N, and E229K near the distal surface, and R368H near the proximal surface. The former two substitutions, Y81N and E229K, caused greatly reduced stability at 4 degrees C. Y81N severely inhibited all substrate turnover, but E229K only inhibited arachidonate turnover and exhibited minimal effect on efficiency of retinoid metabolism and estradiol metabolism. The R368H mutation is relatively conservative, affecting charge-pairing with the deeper-located D374, but it severely inhibited metabolism of all substrates tested, and, like Y81N, expression of the enzyme is less facile than CYP1B1wt. The A330F mutation replaces a small alanine by a bulky phenylalanine in the enzyme active site and had major impact on substrate binding, turnover, uncoupling, and metabolite pattern. CONCLUSION Consistent with the hypothesis, these PCG-related mutations cause identifiable structural changes negatively impacting CYP1B1 biochemistry and stability.
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Mackey DA. Gillies Lecture: Dissecting glaucoma: understanding the molecular risk factors. Clin Exp Ophthalmol 2008; 36:403-9. [DOI: 10.1111/j.1442-9071.2008.001798.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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