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Syx D, Malfait F. Pathogenic mechanisms in genetically defined Ehlers-Danlos syndromes. Trends Mol Med 2024; 30:824-843. [PMID: 39147618 DOI: 10.1016/j.molmed.2024.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 08/17/2024]
Abstract
The Ehlers-Danlos syndromes (EDS) are a group of rare heritable connective tissue disorders, common hallmarks of which are skin hyperextensibility, joint hypermobility, and generalized connective tissue fragility. Currently, 13 EDS types are recognized, caused by defects in 20 genes which consequently alter biosynthesis, organization, and/or supramolecular assembly of collagen fibrils in the extracellular matrix (ECM). Molecular analyses on patient samples (mostly dermal fibroblast cultures), combined with studies on animal models, have highlighted that part of EDS pathogenesis can be attributed to impaired cellular dynamics. Although our understanding of the full extent of (extra)cellular consequences is still limited, this narrative review aims to provide a comprehensive overview of our current knowledge on the extracellular, pericellular, and intracellular alterations implicated in EDS pathogenesis.
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Affiliation(s)
- Delfien Syx
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Fransiska Malfait
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium.
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Foehr R, Anderson K, Dombrowski O, Foehr A, Foehr ED. Dysregulation of extracellular matrix and Lysyl Oxidase in Ehlers-Danlos syndrome type IV skin fibroblasts. Orphanet J Rare Dis 2024; 19:9. [PMID: 38183136 PMCID: PMC10768281 DOI: 10.1186/s13023-023-03007-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 12/19/2023] [Indexed: 01/07/2024] Open
Abstract
BACKGROUND Ehlers-Danlos syndrome Type IV (aka Vascular Ehlers Danlos, or vEDS) is a dominantly inherited mutation in the Collagen 3A1 gene (COL3A1). The disease is characterized by tissue friability and age-related susceptibility to arterial aneurysm, dissection and rupture as well as uterine and bowl tears. These clinical manifestations result in major surgical intervention and decreased life expectancy. Understanding how mutations in COL3A1 impact the structure and function of the extracellular matrix (ECM) is important to managing the disease and finding treatments. RESULTS Skin fibroblasts from vEDS subjects heterozygous for the p.G588S pathogenic variant in the COL3A1 gene and a normal individual were cultured and studied. Proteomics analysis identified dozens of upregulated proteins related to extracellular matrix dysregulation that is characteristic of fibrosis. Gene expression libraries from cultured primary fibroblasts were screened for messenger RNA (mRNA) markers of ECM degradation. The proteomics and targeted gene expression array results were largely consistent with dysregulation of the extracellular matrix in vEDS. The data show upregulation of multiple Collagen proteins and genes, other ECM components, and enzymes related to ECM processing and turn-over. vEDS fibroblasts expressed significantly more cross linked C-Telopeptide of Collagen III (CTXIII) than normal fibroblasts, indicative of Collagen III degradation and turn-over. Further, the expression and activity of Lysyl Oxidase (LOX), an enzyme that initiates covalent cross-linking of soluble collagen and elastin into protease resistant fibers, is elevated in vEDS fibroblasts compared to normal fibroblasts. CONCLUSION Together, these findings suggest dysregulated ECM deposition and processing, reminiscent of a state of fibrosis. Therapeutics that target the dysregulated ECM proteins or help replace damaged tissue may improve clinical outcomes.
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Affiliation(s)
- Reece Foehr
- Kin Therapeutics, 300 Professional Center Drive, Suite #311, Novato, CA, 94947, USA
| | - Keith Anderson
- Kin Therapeutics, 300 Professional Center Drive, Suite #311, Novato, CA, 94947, USA
| | - Owen Dombrowski
- Kin Therapeutics, 300 Professional Center Drive, Suite #311, Novato, CA, 94947, USA
| | - Anna Foehr
- Kin Therapeutics, 300 Professional Center Drive, Suite #311, Novato, CA, 94947, USA
| | - Erik D Foehr
- Kin Therapeutics, 300 Professional Center Drive, Suite #311, Novato, CA, 94947, USA.
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Omar R, Malfait F, Van Agtmael T. Four decades in the making: Collagen III and mechanisms of vascular Ehlers Danlos Syndrome. Matrix Biol Plus 2021; 12:100090. [PMID: 34849481 PMCID: PMC8609142 DOI: 10.1016/j.mbplus.2021.100090] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 10/10/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
Vascular Ehlers Danlos (vEDS) syndrome is a severe multi-systemic connective tissue disorder characterized by risk of dissection and rupture of the arteries, gastro-intestinal tract and gravid uterus. vEDS is caused by mutations in COL3A1, that encodes the alpha 1 chain of type III collagen, which is a major extracellular matrix component of the vasculature and hollow organs. The first causal mutations were identified in the 1980s but progress in our understanding of the pathomolecular mechanisms has been limited. Recently, the application of more refined animal models combined with global omics approaches has yielded important new insights both in terms of disease mechanisms and potential for therapeutic intervention. However, it is also becoming apparent that vEDS is a complex disorder in terms of its molecular disease mechanisms with a poorly understood allelic and mechanistic heterogeneity. In this brief review we will focus our attention on the disease mechanisms of COL3A1 mutations and vEDS, and recent progress in therapeutic approaches using animal models.
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Affiliation(s)
- Ramla Omar
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, G12 8QQ, UK
| | - Fransiska Malfait
- Centre for Medical Genetics, Ghent University Hospital, Belgium
- Department of Biomolecular Medicine, Ghent University, Belgium
| | - Tom Van Agtmael
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, G12 8QQ, UK
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Beyens A, Van Meensel K, Pottie L, De Rycke R, De Bruyne M, Baeke F, Hoebeke P, Plasschaert F, Loeys B, De Schepper S, Symoens S, Callewaert B. Defining the Clinical, Molecular and Ultrastructural Characteristics in Occipital Horn Syndrome: Two New Cases and Review of the Literature. Genes (Basel) 2019; 10:genes10070528. [PMID: 31336972 PMCID: PMC6678539 DOI: 10.3390/genes10070528] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 12/15/2022] Open
Abstract
Occipital horn syndrome (OHS) is a rare connective tissue disorder caused by pathogenic variants in ATP7A, encoding a copper transporter. The main clinical features, including cutis laxa, bony exostoses, and bladder diverticula are attributed to a decreased activity of lysyl oxidase (LOX), a cupro-enzyme involved in collagen crosslinking. The absence of large case series and natural history studies precludes efficient diagnosis and management of OHS patients. This study describes the clinical and molecular characteristics of two new patients and 32 patients previously reported in the literature. We report on the need for long-term specialized care and follow-up, in which MR angiography, echocardiography and spirometry should be incorporated into standard follow-up guidelines for OHS patients, next to neurodevelopmental, orthopedic and urological follow-up. Furthermore, we report on ultrastructural abnormalities including increased collagen diameter, mild elastic fiber abnormalities and multiple autophagolysosomes reflecting the role of lysyl oxidase and defective ATP7A trafficking as pathomechanisms of OHS.
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Affiliation(s)
- Aude Beyens
- Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium
- Department of Dermatology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Kyaran Van Meensel
- Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium
| | - Lore Pottie
- Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium
| | - Riet De Rycke
- Department for Biomedical Molecular Biology, Ghent University, 9000 Ghent, Belgium
- VIB Center for Inflammation Research, 9000 Ghent, Belgium
- Ghent University Expertise Centre for Transmission Electron Microscopy and VIB BioImaging Core, 9000 Ghent, Belgium
| | - Michiel De Bruyne
- Department for Biomedical Molecular Biology, Ghent University, 9000 Ghent, Belgium
- VIB Center for Inflammation Research, 9000 Ghent, Belgium
- Ghent University Expertise Centre for Transmission Electron Microscopy and VIB BioImaging Core, 9000 Ghent, Belgium
| | - Femke Baeke
- Department for Biomedical Molecular Biology, Ghent University, 9000 Ghent, Belgium
- VIB Center for Inflammation Research, 9000 Ghent, Belgium
- Ghent University Expertise Centre for Transmission Electron Microscopy and VIB BioImaging Core, 9000 Ghent, Belgium
| | - Piet Hoebeke
- Department of Urology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Frank Plasschaert
- Department of Orthopedic Surgery, Ghent University Hospital, 9000 Ghent, Belgium
| | - Bart Loeys
- Center for Medical Genetics, University of Antwerp/Antwerp University Hospital, Antwerp, Belgium
| | - Sofie De Schepper
- Department of Dermatology, Ghent University Hospital, 9000 Ghent, Belgium
| | - Sofie Symoens
- Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium
| | - Bert Callewaert
- Center for Medical Genetics Ghent, Ghent University Hospital, 9000 Ghent, Belgium.
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Type III collagen (COL3A1): Gene and protein structure, tissue distribution, and associated diseases. Gene 2019; 707:151-171. [PMID: 31075413 DOI: 10.1016/j.gene.2019.05.003] [Citation(s) in RCA: 163] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/01/2019] [Accepted: 05/02/2019] [Indexed: 02/07/2023]
Abstract
Collagen alpha-1(III) chain, also known as the alpha 1 chain of type III collagen, is a protein that in humans is encoded by the COL3A1 gene. Three alpha 1 chains are required to form the type III collagen molecule which has a long triple-helical domain. Type III collagen, an extracellular matrix protein, is synthesized by cells as a pre-procollagen. It is found as a major structural component in hollow organs such as large blood vessels, uterus and bowel. Other functions of type III collagen include interaction with platelets in the blood clotting cascade and it is also an important signaling molecule in wound healing. Mutations in the COL3A1 gene cause the vascular type of Ehlers-Danlos syndrome (vEDS; OMIM 130050). It is the most serious form of EDS, since patients often die suddenly due to a rupture of large arteries. Inactivation of the murine Col3a1 gene leads to a shorter life span in homozygous mutant mice. The mice die prematurely from a rupture of major arteries mimicking the human vEDS phenotype. The biochemical and cellular effects of COL3A1 mutations have been studied extensively. Most of the glycine mutations lead to the synthesis of type III collagen with reduced thermal stability, which is more susceptible for proteinases. Intracellular accumulation of this normally secreted protein is also found. Ultrastructural analyses have demonstrated dilated rough endoplasmic reticulum and changes in the diameter of collagen fibers. Other clinical conditions associated with type III collagen are several types of fibroses in which increased amounts of type III collagen accumulate in the target organs.
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Targeted next-generation sequencing makes new molecular diagnoses and expands genotype–phenotype relationship in Ehlers–Danlos syndrome. Genet Med 2016; 18:1119-1127. [DOI: 10.1038/gim.2016.14] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 01/14/2016] [Indexed: 01/01/2023] Open
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Expanding the clinical and mutational spectrum of the Ehlers-Danlos syndrome, dermatosparaxis type. Genet Med 2016; 18:882-91. [PMID: 26765342 DOI: 10.1038/gim.2015.188] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/02/2015] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The Ehlers-Danlos syndrome (EDS), dermatosparaxis type, is a recessively inherited connective tissue disorder caused by deficient activity of ADAMTS-2, an enzyme that cleaves the aminoterminal propeptide domain of types I, II, and III procollagen. Only 10 EDS dermatosparaxis patients have been reported, all presenting a recognizable phenotype with characteristic facial gestalt, extreme skin fragility and laxity, excessive bruising, and sometimes major complications due to visceral and vascular fragility. METHODS We report on five new EDS dermatosparaxis patients and provide a comprehensive overview of the current knowledge of the natural history of this condition. RESULTS We identified three novel homozygous loss-of-function mutations (c.2927_2928delCT, p.(Pro976Argfs*42); c.669_670dupG, p.(Pro224Argfs*24); and c.2751-2A>T) and one compound heterozygous mutation (c.2T>C, p.? and c.884_887delTGAA, p.(Met295Thrfs26*)) in ADAMTS2 in five patients from four unrelated families. Three of these displayed a phenotype that was strikingly milder than that of previously reported patients. CONCLUSION This study expands the clinical and molecular spectrum of the dermatosparaxis type of EDS to include a milder phenotypic variant and stresses the importance of good clinical criteria. To address this, we propose an updated set of criteria that accurately captures the multisystemic nature of the dermatosparaxis type of EDS.Genet Med 18 9, 882-891.
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Syx D, Guillemyn B, Symoens S, Sousa AB, Medeira A, Whiteford M, Hermanns-Lê T, Coucke PJ, De Paepe A, Malfait F. Defective Proteolytic Processing of Fibrillar Procollagens and Prodecorin Due to Biallelic BMP1 Mutations Results in a Severe, Progressive Form of Osteogenesis Imperfecta. J Bone Miner Res 2015; 30:1445-56. [PMID: 25656619 DOI: 10.1002/jbmr.2473] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 01/25/2015] [Accepted: 01/31/2015] [Indexed: 11/10/2022]
Abstract
Whereas the vast majority of osteogenesis imperfecta (OI) is caused by autosomal dominant defects in the genes encoding type I procollagen, mutations in a myriad of genes affecting type I procollagen biosynthesis or bone formation and homeostasis have now been associated with rare autosomal recessive OI forms. Recently, homozygous or compound heterozygous mutations in BMP1, encoding the metalloproteases bone morphogenetic protein-1 (BMP1) and its longer isoform mammalian Tolloid (mTLD), were identified in 5 children with a severe autosomal recessive form of OI and in 4 individuals with mild to moderate bone fragility. BMP1/mTLD functions as the procollagen carboxy-(C)-proteinase for types I to III procollagen but was also suggested to participate in amino-(N)-propeptide cleavage of types V and XI procollagens and in proteolytic trimming of other extracellular matrix (ECM) substrates. We report the phenotypic characteristics and natural history of 4 adults with severe, progressive OI characterized by numerous fractures, short stature with rhizomelic shortening, and deformity of the limbs and variable kyphoscoliosis, in whom we identified novel biallelic missense and frameshift mutations in BMP1. We show that BMP1/mTLD-deficiency in humans not only results in delayed cleavage of the type I procollagen C-propeptide but also hampers the processing of the small leucine-rich proteoglycan prodecorin, a regulator of collagen fibrillogenesis. Immunofluorescent staining of types I and V collagen and transmission electron microscopy of the dermis show impaired assembly of heterotypic type I/V collagen fibrils in the ECM. Our study thus highlights the severe and progressive nature of BMP1-associated OI in adults and broadens insights into the functional consequences of BMP1/mTLD-deficiency on ECM organization.
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Affiliation(s)
- Delfien Syx
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Brecht Guillemyn
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Sofie Symoens
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Ana Berta Sousa
- Department of Genetics, Hospital de Santa Maria de Lisboa, Lisbon, Portugal
| | - Ana Medeira
- Department of Genetics, Hospital de Santa Maria de Lisboa, Lisbon, Portugal
| | - Margo Whiteford
- Department of Clinical Genetics, Southern General Hospital, Glasgow, United Kingdom
| | - Trinh Hermanns-Lê
- Department of Dermatopathology, Liège University Hospital, Liège, Belgium
| | - Paul J Coucke
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Anne De Paepe
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Fransiska Malfait
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
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9
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Stembridge NS, Vandersteen AM, Ghali N, Sawle P, Nesbitt M, Pollitt RC, Ferguson DJP, Holden S, Elmslie F, Henderson A, Hulmes DJS, Pope F. Clinical, structural, biochemical and X-ray crystallographic correlates of pathogenicity for variants in the C-propeptide region of theCOL3A1gene. Am J Med Genet A 2015; 167A:1763-72. [DOI: 10.1002/ajmg.a.37081] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 03/12/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Natasha S. Stembridge
- Ehlers-Danlos Syndrome; National Diagnostic Service Northwick Park and St. Mark's Hospitals; Harrow UK
| | | | - Neeti Ghali
- Ehlers-Danlos Syndrome; National Diagnostic Service Northwick Park and St. Mark's Hospitals; Harrow UK
| | - Philip Sawle
- Ehlers-Danlos Syndrome; National Diagnostic Service Northwick Park and St. Mark's Hospitals; Harrow UK
| | - Mandy Nesbitt
- Ehlers-Danlos Syndrome; National Diagnostic Service; Sheffield Diagnostic Genetics Service; Sheffield Children's Hospital; Sheffield UK
| | - Rebecca C. Pollitt
- Ehlers-Danlos Syndrome; National Diagnostic Service; Sheffield Diagnostic Genetics Service; Sheffield Children's Hospital; Sheffield UK
| | - David J. P. Ferguson
- Nuffield Department of Clinical Laboratory Science; John Radcliffe Hospital; Oxford UK
| | - Simon Holden
- East Anglia Regional Genetics Service; Addenbrooke's Hospital; Cambridge UK
| | - Frances Elmslie
- South West Thames Regional Genetics Service; St. George's Healthcare NHS Trust; London UK
| | - Alex Henderson
- Institute of Genetic Medicine; International Centre for Life; Newcastle upon Tyne UK
| | - David J. S. Hulmes
- Unité Mixte de Recherche 5305; Institut de Biologie et Chimie des Protéines; Centre National de la Recherche Scientifique; Université Lyon 1; Lyon France
| | - F.Michael Pope
- Ehlers-Danlos Syndrome; National Diagnostic Service Northwick Park and St. Mark's Hospitals; Harrow UK
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Vandesompele J, De Preter K, Pattyn F, Poppe B, Van Roy N, De Paepe A, Speleman F. Accurate normalization of real-time quantitative RT-PCR data by geometric averaging of multiple internal control genes. Genome Biol 2002. [PMID: 12184808 DOI: 10.1186/gb-2007-3-8-research0034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/14/2023] Open
Abstract
BACKGROUND Gene-expression analysis is increasingly important in biological research, with real-time reverse transcription PCR (RT-PCR) becoming the method of choice for high-throughput and accurate expression profiling of selected genes. Given the increased sensitivity, reproducibility and large dynamic range of this methodology, the requirements for a proper internal control gene for normalization have become increasingly stringent. Although housekeeping gene expression has been reported to vary considerably, no systematic survey has properly determined the errors related to the common practice of using only one control gene, nor presented an adequate way of working around this problem. RESULTS We outline a robust and innovative strategy to identify the most stably expressed control genes in a given set of tissues, and to determine the minimum number of genes required to calculate a reliable normalization factor. We have evaluated ten housekeeping genes from different abundance and functional classes in various human tissues, and demonstrated that the conventional use of a single gene for normalization leads to relatively large errors in a significant proportion of samples tested. The geometric mean of multiple carefully selected housekeeping genes was validated as an accurate normalization factor by analyzing publicly available microarray data. CONCLUSIONS The normalization strategy presented here is a prerequisite for accurate RT-PCR expression profiling, which, among other things, opens up the possibility of studying the biological relevance of small expression differences.
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Affiliation(s)
- Jo Vandesompele
- Center for Medical Genetics, Ghent University Hospital 1K5, De Pintelaan 185, B-9000 Ghent, Belgium.
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11
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Vandesompele J, De Preter K, Pattyn F, Poppe B, Van Roy N, De Paepe A, Speleman F. Accurate normalization of real-time quantitative RT-PCR data by geometric averaging of multiple internal control genes. Genome Biol 2002; 3:RESEARCH0034. [PMID: 12184808 PMCID: PMC126239 DOI: 10.1186/gb-2002-3-7-research0034] [Citation(s) in RCA: 14097] [Impact Index Per Article: 640.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2001] [Revised: 04/10/2002] [Accepted: 05/07/2002] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Gene-expression analysis is increasingly important in biological research, with real-time reverse transcription PCR (RT-PCR) becoming the method of choice for high-throughput and accurate expression profiling of selected genes. Given the increased sensitivity, reproducibility and large dynamic range of this methodology, the requirements for a proper internal control gene for normalization have become increasingly stringent. Although housekeeping gene expression has been reported to vary considerably, no systematic survey has properly determined the errors related to the common practice of using only one control gene, nor presented an adequate way of working around this problem. RESULTS We outline a robust and innovative strategy to identify the most stably expressed control genes in a given set of tissues, and to determine the minimum number of genes required to calculate a reliable normalization factor. We have evaluated ten housekeeping genes from different abundance and functional classes in various human tissues, and demonstrated that the conventional use of a single gene for normalization leads to relatively large errors in a significant proportion of samples tested. The geometric mean of multiple carefully selected housekeeping genes was validated as an accurate normalization factor by analyzing publicly available microarray data. CONCLUSIONS The normalization strategy presented here is a prerequisite for accurate RT-PCR expression profiling, which, among other things, opens up the possibility of studying the biological relevance of small expression differences.
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Affiliation(s)
- Jo Vandesompele
- Center for Medical Genetics, Ghent University Hospital 1K5, De Pintelaan 185, B-9000 Ghent, Belgium.
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12
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Habib K, Memon MA, Reid DA, Fairbrother BJ. Spontaneous common iliac arteries rupture in Ehlers-Danlos syndrome type IV: report of two cases and review of the literature. Ann R Coll Surg Engl 2001; 83:96-104. [PMID: 11320937 PMCID: PMC2503357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
Two patients with previously undiagnosed Ehlers-Danlos syndrome type IV (EDS IV) presented acutely with clinical features suggestive of hypovolemic shock. Emergency laparotomies in both of them revealed spontaneous rupture of the common iliac arteries. The clinical features, operative findings, surgical approach, outcome and implications are discussed.
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Affiliation(s)
- K Habib
- Department of Surgery, King's Mill Centre for Healthcare Services, Mansfield Road, Sutton-in-Ashfield, Nottinghamshire NG17 4JL, UK.
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13
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Nuytinck L, Dalgleish R, Spotila L, Renard JP, Van Regemorter N, De Paepe A. Substitution of glycine-661 by serine in the alpha1(I) and alpha2(I) chains of type I collagen results in different clinical and biochemical phenotypes. Hum Genet 1996; 97:324-9. [PMID: 8786074 DOI: 10.1007/bf02185764] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have characterised a point mutation causing the substitution of serine for glycine at position 661 of the alpha1(I) chain of type I collagen in a child with a severe form of osteogenesis imperfecta. An identical glycine substitution in the alpha2(I) chain was previously detected in a woman with post-menopausal osteoporosis. Two of her sons were heterozygous for the mutation and the third son was homozygous as a result of uniparental isodisomy. Biochemical profiles of the type I collagen heterotrimers were studied in each of the patients and compared with a control. Medium and cell-layer collagens were overmodified in all patients. Overmodification was obvious in the patient with the alpha 1(I) mutation but mild in the patients with the alpha 2(I) mutation, being slightly less evident in the heterozygote than in the homozygote. Investigation of the melting curves of the mutant collagen trimers in all three patients showed the same slight decrease in thermal stability and, hence, a lack of correlation with phenotypic severity. In contrast, the degree of overmodification of the collagen alpha chains was correlated with the phenotypic severity. The clinical observations in these patients illustrate the possibly predominant role of mutations in the collagen alpha1(I) chains over the same mutations in the alpha2(I) chains in determining the clinical outcome.
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Affiliation(s)
- L Nuytinck
- Centre for Medical Genetics, University Hospital Ghent, Belgium
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14
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Wimmer PJ, Howes DS, Rumoro DP, Carbone M. Fatal vascular catastrophe in Ehlers-Danlos syndrome: a case report and review. J Emerg Med 1996; 14:25-31. [PMID: 8655934 DOI: 10.1016/0736-4679(95)02039-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The Ehlers-Danlos syndrome (EDS) is a group of hereditary connective tissue disorders that are characterized by abnormalities of the skin, joints, and a diversity of other phenotypic manifestations. An awareness of the disease is vital for optimal outcome in this rare group of patients who may present with a variety of life-threatening illnesses. Ehlers-Danlos type IV has been associated with vascular catastrophes, perforated viscous, ruptured uterus, and pneumothorax (1-4). We present a case of aneurysmal formation and spontaneous rupture of the great vessels in a 15-year-old male with EDS type IV, who remained undiagnosed until the time of autopsy.
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Affiliation(s)
- P J Wimmer
- Section of Emergency Medicine, University of Chicago, Illinois 60637, USA
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15
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Godfrey M, Cisler J, Geerts ML, Christiano A, Uitto J, De Bie S, DePaepe A. Fibrillin immunofluorescence in pseudoxanthoma elasticum. J Am Acad Dermatol 1995; 32:589-94. [PMID: 7896947 DOI: 10.1016/0190-9622(95)90342-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Pseudoxanthoma elasticum (PXE) is a rare heritable connective tissue disorder manifested by skin, ocular, and cardiovascular anomalies. The basic defect is unknown; however, the microscopic findings are indicative of defects in elastic fibers. Among the components of the elastic fibers are elastin and elastin-associated microfibrils. OBJECTIVE We assessed the fidelity of this fibrillar system in PXE with the use of antibodies to fibrillin, a major component of elastin-associated microfibrils. METHODS Using a well-established immunofluorescence assay, we studied fibrillin deposition in dermal fibroblast cultures from 16 patients with PXE. RESULTS Six of the 16 patients (37%) showed some abnormality of fibrillin deposition in fibroblasts derived from lesional skin. Fibroblasts from nonlesional skin displayed normal fibrillin immunofluorescence. The only sibship studied, however, was discordant for fibrillin immunostaining. CONCLUSION Unlike the findings in Marfan syndrome, these data are not suggestive of causal fibrillin defects in PXE.
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Affiliation(s)
- M Godfrey
- Department of Pediatrics, University of Nebraska Medical Center 68198-5430
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Mackay K, De Paepe A, Nuytinck L, Dalgleish R. Substitution of glycine-172 by arginine in the alpha 1 chain of type I collagen in a patient with osteogenesis imperfecta, type III. Hum Mutat 1994; 3:324-6. [PMID: 8019571 DOI: 10.1002/humu.1380030327] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- K Mackay
- Department of Genetics, University of Leicester
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Nuytinck L, De Paepe A, Renard JP, Adriaens F, Leroy J. Single-strand conformation polymorphism (SSCP) analysis of the COL3A1 gene detects a mutation that results in the substitution of glycine 1009 to valine and causes severe Ehlers-Danlos syndrome type IV. Hum Mutat 1994; 3:268-74. [PMID: 8019562 DOI: 10.1002/humu.1380030315] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A single base mismatch was detected by single-strand conformation polymorphism (SSCP) of the collagen type III gene in a patient with Ehlers-Danlos syndrome type IV. The patient's fibroblasts secreted both normal and slowly migrating type III procollagen molecules. Two-dimensional CNBr peptide mapping suggested that the defect was localised in the CB9 peptide or the C-propeptide region of the alpha 1 (III)-chain. Analysis of a set of restriction-endonuclease-digested fragments of an amplified cDNA sequence encoding CB9, identified a single-strand conformation polymorphism and localized it within a region of 79 bp corresponding to the carboxyl-terminal end of the CB9 peptide of the alpha 1(III)-chain. DNA sequence analysis demonstrated that the patient was heterozygous for a point mutation converting G to T at base pair 3440 of the collagen alpha 1(III) cDNA resulting in the substitution of glycine with valine at amino acid position 1009 of the alpha 1(III)-chain. The mutation in this patient lies within a region of mutations at the carboxyl-terminal end of the type III collagen alpha-helix which all produce a severe "acrogeric" form of EDS IV.
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Affiliation(s)
- L Nuytinck
- Centre for Medical Genetics, University Hospital Gent, Belgium
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Richards A, Narcisi P, Lloyd J, Ferguson C, Pope FM. The substitution of glycine 661 by arginine in type III collagen produces mutant molecules with different thermal stabilities and causes Ehlers-Danlos syndrome type IV. J Med Genet 1993; 30:690-3. [PMID: 8411057 PMCID: PMC1016501 DOI: 10.1136/jmg.30.8.690] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Previous studies have shown that Ehlers-Danlos syndrome type IV (EDS IV) is caused by mutations of type III collagen (COL3A1). Here we have characterised the most amino-terminal glycine substitution so far described in a patient with EDS IV. A combination of peptide mapping and chemical cleavage analysis of cDNA localised the mutation in cyanogen bromide peptide CB5. Sequence analysis showed a G to A mutation, converting glycine 661 to arginine, which was a new dominant mutation. Analysis of type III collagen secreted by cultured fibroblasts showed an overmodified mutant protein with normal thermal stability. However, the intracellularly retained form melted 2 degrees C lower than normal. This indicated that molecules resulting from the same mutation can differ in their thermal stabilities.
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Affiliation(s)
- A Richards
- Dermatology Research Group, Clinical Research Centre, Harrow, Middlesex, UK
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De Paepe A, Leroy JG, Nuytinck L, Meire F, Capoen J. Osteoporosis-pseudoglioma syndrome. AMERICAN JOURNAL OF MEDICAL GENETICS 1993; 45:30-7. [PMID: 8418655 DOI: 10.1002/ajmg.1320450110] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Two patients with osteoporosis pseudoglioma syndrome are described. Both are single children, born to nonconsanguineous, healthy parents. The first patient, a 17-year-old girl, had serious visual impairment since birth. She is severely dwarfed and has major skeletal deformities resulting in inability to walk since age 2 years. The second patient is an 18-year-old girl with unilateral neonatal blindness, short stature and deformities, mainly of pelvis and lower limbs. She has been able to walk with support up to now. The clinical and radiological findings in these 2 patients reflect the clinical variability of the condition. Results of collagen studies in both patients are normal and differentiate this condition clearly from severe osteogenesis imperfecta, which it resembles.
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Affiliation(s)
- A De Paepe
- Department of Medical Genetics, University Hospital Gent, Belgium
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