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Chawla HS, Kosta S, Namdeo C, Kataria R, Bhatia K, Sahu R, Joshi P. Genotype Study of Filaggrin Gene Loss-of-Function Mutations in Central India Population with Atopic Dermatitis and Ichthyosis Vulgaris. Indian Dermatol Online J 2023; 14:611-615. [PMID: 37727564 PMCID: PMC10506825 DOI: 10.4103/idoj.idoj_636_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 04/19/2023] [Accepted: 05/22/2023] [Indexed: 09/21/2023] Open
Abstract
Background A genotype study of filaggrin gene loss-of-function mutations in central India can provide valuable insights into the prevalence and association of these mutations with atopic dermatitis (AD) and ichthyosis vulgaris (IV) in the region. The FLG R501X and 2282del4 are both genetic variants in the human gene called filaggrin gene (FLG), which encodes a protein that plays an important role in the formation and maintenance of the skin barrier. In this study, we determined the FLG R501X and 2282del4 variants association with both AD and IV in Central Indian populations. Materials and Methods This case-control study was conducted in the Departments of Dermatology and Molecular and Virology Research and Diagnostic Laboratory at Sri Aurobindo Medical College and Post Graduate Institute, Indore (Madhya Pradesh). The study was approved by the Clinical Research and Ethics Committee. A total of 180 patients aged between 3 months - 60 years who attended the skin outpatient department between March-2021 to June-2022 were recruited in this study. Among them, 60 patients were in AD-group, 60 patients in IV-group, and 60 patients were in the healthy control group. Polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) was used in genotyping for FLG mutations (R501X and 2282del4). Results The most common FLG mutations were R501X (31.6% and 23.3%) and 2282del4 (18.3% and 13.3%) in AD and IV patients with heterozygous (AT) genotype, respectively. The combined mutation (FLG R501X and 2282del4) association was 10% and 5% in the AD and IV groups with heterozygous (AT) genotype, respectively, and in all the patients of control group with wild genotype (AA). There were no significant (P = 0.09) associations found with 2282del14 genotype. Conclusion The R501X mutation in the gene encoding filaggrin is one of the robust genetic associations of AD and IV. The 2282del4 polymorphism was marginally less as compared to R501X.
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Affiliation(s)
- Harsimran S. Chawla
- Department of Dermatology, Venerology and Leprosy, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Susmit Kosta
- Department of Molecular and Virology Research and Diagnostic Laboratory, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Chaitanya Namdeo
- Department of Dermatology, Venerology and Leprosy, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Rajesh Kataria
- Department of Dermatology, Venerology and Leprosy, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Kailash Bhatia
- Department of Dermatology, Venerology and Leprosy, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Roshni Sahu
- Department of Molecular and Virology Research and Diagnostic Laboratory, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
| | - Pallavi Joshi
- Department of Molecular and Virology Research and Diagnostic Laboratory, Sri Aurobindo Medical College and Post Graduate Institute, Sri Aurobindo University, Indore, Madhya Pradesh, India
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Kalb B, Marenholz I, Jeanrenaud ACSN, Meixner L, Arnau-Soler A, Rosillo-Salazar OD, Ghauri A, Cibin P, Blümchen K, Schlags R, Hansen G, Seidenberg J, Keil T, Lau S, Niggemann B, Beyer K, Lee YA. Filaggrin loss-of-function mutations are associated with persistence of egg and milk allergy. J Allergy Clin Immunol 2022; 150:1125-1134. [PMID: 35714843 DOI: 10.1016/j.jaci.2022.05.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 04/12/2022] [Accepted: 05/04/2022] [Indexed: 11/19/2022]
Abstract
BACKGROUND A genetic defect in the epidermal barrier protein filaggrin plays a major role in the etiology of eczema and associated allergic airways diseases. However, it is still controversial to what extend loss-of-function (LOF) mutations in the filaggrin gene (FLG) contribute to the development and persistence of food allergies. OBJECTIVE We tested association of FLG LOF mutations with allergic reactions to diverse foods and investigated their potential effect on the persistence of early food allergies. METHODS We recruited 890 children with challenge-proven food allergy for the German Genetics of Food Allergy Study (GOFA). Longitudinal data were available for 684 children. All children were clinically characterized, including their allergic responses to specific foods, and genotyped for the four most common LOF mutations in FLG; R501X, 2282del4, R2447X, and S3247X. Associations between FLG mutations and food allergies were analyzed by logistic regression using the German Multicenter Allergy Study cohort as control population. RESULTS FLG mutations were associated with allergies to diverse foods including hen's egg (HE), cow's milk (CM), peanut, hazelnut, fish, soy, cashew, walnut, and sesame with similar risk estimates. Effects remained significant after adjusting for the eczema status. Interestingly, FLG mutations increased the risk of a persistent course of HE and CM allergy. CONCLUSION Using the gold standard for food allergy diagnosis, we demonstrate that FLG LOF mutations confer a risk of any food allergy independent of eczema. They predispose to the persistence of HE and CM allergy and should be considered in the assessment of tolerance development.
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Affiliation(s)
- Birgit Kalb
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany; Department of Pediatric Respiratory Medicine, Immunology, and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingo Marenholz
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Alexander C S N Jeanrenaud
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Lara Meixner
- Department of Pediatric Respiratory Medicine, Immunology, and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Aleix Arnau-Soler
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Oscar D Rosillo-Salazar
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ahla Ghauri
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Penelope Cibin
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Katharina Blümchen
- Department of Allergy, Pulmonology and Cystic Fibrosis, Children's Hospital, Goethe University, Frankfurt am Main, Germany
| | - Rupert Schlags
- Department of Pediatric Pneumology and Allergology, Wangen Hospital, Wangen, Germany
| | - Gesine Hansen
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Jürgen Seidenberg
- Department of Pediatric Pneumology and Allergology, Neonatology and Intensive Care, Medical Campus of University Oldenburg, Oldenburg, Germany
| | - Thomas Keil
- Institute of Social Medicine, Epidemiology and Health Economics, Charité-Universitätsmedizin Berlin, Berlin, Germany; Institute for Clinical Epidemiology and Biometry, University of Würzburg, Würzburg, Germany
| | - Susanne Lau
- Department of Pediatric Respiratory Medicine, Immunology, and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Bodo Niggemann
- Department of Pediatric Respiratory Medicine, Immunology, and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Kirsten Beyer
- Department of Pediatric Respiratory Medicine, Immunology, and Critical Care Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Young-Ae Lee
- Max-Delbrück-Center for Molecular Medicine (MDC), Berlin, Germany; Clinic for Pediatric Allergy, Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Xu X, Ma Q, Lin M, Liu M, Huang C, Ying J, Ye J. A loss of function mutation in the filaggrin gene associated with ichthyosis vulgaris and rheumatoid arthritis. EUR J INFLAMM 2021. [DOI: 10.1177/20587392211032805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Introduction Mutations in the filaggrin ( FLG) gene are known to cause ichthyosis vulgaris. Methods We used whole-genome sequencing (WGS) technology to investigate the genetic causes of rare and complex inherited diseases including rheumatoid arthritis, ichthyosis, and congenital fibrosis of the extraocular muscles type 1 (CFEOM1) in a Chinese family. WGS was performed in four topics, and the identified candidate mutations were further verified through Sanger sequencing. Results We identified a mutation in FLG gene (g.152280098 C>A, p.E2422∗) that may be associated with ichthyosis and arthritis. Moreover, a mutation in KIF21A (g.39726207 G>A, p.R954 W) was also determined in affected members as the cause of CFEOM1. The gene interaction network demonstrated an interesting correlation between FLG and genes associated with arthritis and ichthyosis. Functional enrichment analysis of these interacting genes revealed several possible pathways that might be linked to arthritis and ichthyosis. Conclusion In general, we confirmed a loss of function mutation in the FLG gene associated with ichthyosis vulgaris and rheumatoid arthritis in this family.
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Affiliation(s)
- Xinxin Xu
- Department of Ophthalmology, Guiyang Maternal and Child Health Care Hospital, Guiyang, China
| | - Qingqing Ma
- Central Laboratory, Guizhou Aerospace Hospital, Zunyi, China
| | - Mu Lin
- Central Laboratory, Guizhou Aerospace Hospital, Zunyi, China
| | - Mubo Liu
- Central Laboratory, Guizhou Aerospace Hospital, Zunyi, China
| | - Chaolin Huang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Jianchao Ying
- Central Laboratory, Institute of Emergency Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jun Ye
- Department of Clinical Laboratory, The Second Affiliated Hospital of Guizhou Medical University, Kaili, China
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van Leersum FS, Nagtzaam IF, van Oosterhoud CN, Ghesquiere SAI, Brandts RRHFJ, Gostyński A, Steijlen PM, van Geel M. Improving the diagnostic yield for filaggrin: Concealed mutations in the Dutch population. J Allergy Clin Immunol 2020; 145:1704-1706.e2. [PMID: 32018027 DOI: 10.1016/j.jaci.2020.01.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/21/2020] [Accepted: 01/24/2020] [Indexed: 10/25/2022]
Affiliation(s)
- Frank S van Leersum
- Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands.
| | - Ivo F Nagtzaam
- Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands
| | | | - Stijn A I Ghesquiere
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Roel R H F J Brandts
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Antoni Gostyński
- Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Peter M Steijlen
- Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Michel van Geel
- Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands; GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands; Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
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Review-Current Concepts in Inflammatory Skin Diseases Evolved by Transcriptome Analysis: In-Depth Analysis of Atopic Dermatitis and Psoriasis. Int J Mol Sci 2020; 21:ijms21030699. [PMID: 31973112 PMCID: PMC7037913 DOI: 10.3390/ijms21030699] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 12/14/2022] Open
Abstract
During the last decades, high-throughput assessment of gene expression in patient tissues using microarray technology or RNA-Seq took center stage in clinical research. Insights into the diversity and frequency of transcripts in healthy and diseased conditions provide valuable information on the cellular status in the respective tissues. Growing with the technique, the bioinformatic analysis toolkit reveals biologically relevant pathways which assist in understanding basic pathophysiological mechanisms. Conventional classification systems of inflammatory skin diseases rely on descriptive assessments by pathologists. In contrast to this, molecular profiling may uncover previously unknown disease classifying features. Thereby, treatments and prognostics of patients may be improved. Furthermore, disease models in basic research in comparison to the human disease can be directly validated. The aim of this article is not only to provide the reader with information on the opportunities of these techniques, but to outline potential pitfalls and technical limitations as well. Major published findings are briefly discussed to provide a broad overview on the current findings in transcriptomics in inflammatory skin diseases.
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Yang Y, Liu W, Zhao Z, Zhang Y, Xiao H, Luo B. Filaggrin gene polymorphism associated with Epstein-Barr virus-associated tumors in China. Virus Genes 2017; 53:532-537. [PMID: 28455573 DOI: 10.1007/s11262-017-1463-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2017] [Accepted: 04/22/2017] [Indexed: 01/04/2023]
Abstract
Mutations of filaggrin gene (FLG) have been identified as the cause of ichthyosis vulgaris, while recently FLG mutations were found to be associated with gastric cancer. This study aimed to investigate the association of filaggrin polymorphism with Epstein-Barr virus-associated tumors in China. A total of 200 patients with three types of tumors and 117 normal control samples were genotyped at three common FLG mutation loci (rs3126085, K4671X, R501X) by using Sequenom MassARRAY technique. The χ 2 test was used to evaluate the relationship between the mutation and the three kinds of tumors. A two-sided P value of <0.05 was considered statistically significant. The results showed that two single-nucleotide polymorphism (SNP) loci (rs3126085, K4671X) were significantly associated with nasopharyngeal carcinoma in genetic model. In addition, the two SNPs K4671X and rs3126085 were related to Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and EBV-negative gastric carcinoma (EBVnGC), respectively. Furthermore, allele distributions in EBVaGC and EBVnGC were verified to be different in both SNP loci.
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Affiliation(s)
- Yang Yang
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China
| | - Wen Liu
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China
| | - Zhenzhen Zhao
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China
| | - Yan Zhang
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China.,Department of Clinical Laboratory, Central Hospital of Zibo, 54 Gongqingtuan Road, Zibo, 255036, China
| | - Hua Xiao
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China
| | - Bing Luo
- Department of Medical Microbiology, Qingdao University Medical College, 38 Dengzhou Road, Qingdao, 266021, China.
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Blunder S, Rühl R, Moosbrugger-Martinz V, Krimmel C, Geisler A, Zhu H, Crumrine D, Elias PM, Gruber R, Schmuth M, Dubrac S. Alterations in Epidermal Eicosanoid Metabolism Contribute to Inflammation and Impaired Late Differentiation in FLG-Mutated Atopic Dermatitis. J Invest Dermatol 2016; 137:706-715. [PMID: 27793761 DOI: 10.1016/j.jid.2016.09.034] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 09/04/2016] [Accepted: 09/12/2016] [Indexed: 12/29/2022]
Abstract
Loss-of-function mutations in the FLG gene cause ichthyosis vulgaris (IV) and represent the major predisposing genetic risk factor for atopic dermatitis (AD). Although both conditions are characterized by epidermal barrier impairment, AD also exhibits signs of inflammation. This work was aimed at delineating the role of FLG loss-of-function mutations on eicosanoid metabolism in IV and AD. Using human epidermal equivalents (HEEs) generated with keratinocytes isolated from nonlesional skin of patients with FLG wild-type AD (WT/WT), FLG-mutated AD (FLG/WT), IV (FLG/FLG), or FLG WT control skin, we assessed the potential autocrine role of epidermal-derived eicosanoids in FLG-associated versus FLG-WT AD pathogenesis. Ultrastructural analyses demonstrated abnormal stratum corneum lipid architecture in AD and IV HEEs, independent of FLG genotype. Both AD (FLG/WT) and IV (FLG/FLG) HEEs showed impaired late epidermal differentiation. Only AD (FLG/WT) HEEs exhibited significantly increased levels of inflammatory cytokines. Analyses of lipid mediators revealed increased arachidonic acid and 12-lipoxygenase metabolites. Whereas treatment of control HEEs with arachidonic acid increased expression of inflammatory cytokines, 12-hydroxy-eicosatetraenoic acid attenuated expression of late differentiation markers. Thus, FLG mutations lead to alterations in epidermal eicosanoid metabolism that could serve as an autocrine trigger of inflammation and impaired late epidermal differentiation in AD.
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Affiliation(s)
- Stefan Blunder
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Ralph Rühl
- MTA-DE Public Health Research Group of the Hungarian Academy of Sciences, Faculty of Public Health, University of Debrecen, Debrecen, Hungary; Paprika Bioanalytics, Debrecen, Hungary
| | - Verena Moosbrugger-Martinz
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Christine Krimmel
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Anita Geisler
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Huiting Zhu
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria; Department of Dermatology, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing, China
| | - Debra Crumrine
- Department of Dermatology, University of California, San Francisco, California, USA
| | - Peter M Elias
- Department of Dermatology, University of California, San Francisco, California, USA
| | - Robert Gruber
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria; Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Matthias Schmuth
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Sandrine Dubrac
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria.
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Sekiya A, Kono M, Tsujiuchi H, Kobayashi T, Nomura T, Kitakawa M, Suzuki N, Yamanaka K, Sueki H, McLean W, Shimizu H, Akiyama M. Compound heterozygotes for filaggrin gene mutations do not always show severe atopic dermatitis. J Eur Acad Dermatol Venereol 2016; 31:158-162. [DOI: 10.1111/jdv.13871] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 06/16/2016] [Indexed: 12/24/2022]
Affiliation(s)
- A. Sekiya
- Department of Dermatology; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - M. Kono
- Department of Dermatology; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - H. Tsujiuchi
- Department of Dermatology; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - T. Kobayashi
- Department of Dermatology; Nagoya University Graduate School of Medicine; Nagoya Japan
| | - T. Nomura
- Department of Dermatology; Hokkaido University Graduate School of Medicine; Sapporo Japan
| | - M. Kitakawa
- Department of Dermatology; Showa University School of Medicine; Tokyo Japan
| | - N. Suzuki
- Department of Dermatology; Toyohashi Municipal Hospital; Toyohashi Japan
| | - K. Yamanaka
- Department of Dermatology; Mie University School of Medicine; Tsu Japan
| | - H. Sueki
- Department of Dermatology; Showa University School of Medicine; Tokyo Japan
| | - W.H.I. McLean
- Centre for Dermatology and Genetic Medicine; College of Life Sciences and College of Medicine; Dentistry & Nursing; University of Dundee; Dundee UK
| | - H. Shimizu
- Department of Dermatology; Hokkaido University Graduate School of Medicine; Sapporo Japan
| | - M. Akiyama
- Department of Dermatology; Nagoya University Graduate School of Medicine; Nagoya Japan
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Bandier J, Carlsen B, Rasmussen M, Petersen L, Johansen J. Skin reaction and regeneration after single sodium lauryl sulfate exposure stratified by filaggrin genotype and atopic dermatitis phenotype. Br J Dermatol 2015; 172:1519-1529. [DOI: 10.1111/bjd.13651] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2015] [Indexed: 12/27/2022]
Affiliation(s)
- J. Bandier
- National Allergy Research Centre; Department of Dermato-Allergology; Copenhagen University Hospital Gentofte; Kildegårdsvej 28 2900 Hellerup Denmark
| | - B.C. Carlsen
- National Allergy Research Centre; Department of Dermato-Allergology; Copenhagen University Hospital Gentofte; Kildegårdsvej 28 2900 Hellerup Denmark
| | - M.A. Rasmussen
- Faculty of Science; University of Copenhagen; Frederiksberg Denmark
| | - L.J. Petersen
- Department of Nuclear Medicine; Aalborg University Hospital; Aalborg Denmark
- Department of Clinical Medicine; Aalborg University Hospital; Aalborg Denmark
| | - J.D. Johansen
- National Allergy Research Centre; Department of Dermato-Allergology; Copenhagen University Hospital Gentofte; Kildegårdsvej 28 2900 Hellerup Denmark
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Sebaceous gland, hair shaft, and epidermal barrier abnormalities in keratosis pilaris with and without filaggrin deficiency. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1012-21. [PMID: 25660180 DOI: 10.1016/j.ajpath.2014.12.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/19/2014] [Accepted: 12/17/2014] [Indexed: 01/07/2023]
Abstract
Although keratosis pilaris (KP) is common, its etiopathogenesis remains unknown. KP is associated clinically with ichthyosis vulgaris and atopic dermatitis and molecular genetically with filaggrin-null mutations. In 20 KP patients and 20 matched controls, we assessed the filaggrin and claudin 1 genotypes, the phenotypes by dermatoscopy, and the morphology by light and transmission electron microscopy. Thirty-five percent of KP patients displayed filaggrin mutations, demonstrating that filaggrin mutations only partially account for the KP phenotype. Major histologic and dermatoscopic findings of KP were hyperkeratosis, hypergranulosis, mild T helper cell type 1-dominant lymphocytic inflammation, plugging of follicular orifices, striking absence of sebaceous glands, and hair shaft abnormalities in KP lesions but not in unaffected skin sites. Changes in barrier function and abnormal paracellular permeability were found in both interfollicular and follicular stratum corneum of lesional KP, which correlated ultrastructurally with impaired extracellular lamellar bilayer maturation and organization. All these features were independent of filaggrin genotype. Moreover, ultrastructure of corneodesmosomes and tight junctions appeared normal, immunohistochemistry for claudin 1 showed no reduction in protein amounts, and molecular analysis of claudin 1 was unremarkable. Our findings suggest that absence of sebaceous glands is an early step in KP pathogenesis, resulting in downstream hair shaft and epithelial barrier abnormalities.
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Carlsen BC, Meldgaard M, Johansen JD, Thyssen JP, Menné T, Szecsi PB, Stender S. Filaggrin compound heterozygous patients carry mutations intransposition. Exp Dermatol 2013; 22:572-5. [DOI: 10.1111/exd.12199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2013] [Indexed: 12/23/2022]
Affiliation(s)
- Berit C. Carlsen
- Department of Dermato-Allergology; National Allergy Research Centre; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Michael Meldgaard
- Department of Clinical Biochemistry; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Jeanne D. Johansen
- Department of Dermato-Allergology; National Allergy Research Centre; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Jacob P. Thyssen
- Department of Dermato-Allergology; National Allergy Research Centre; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Torkil Menné
- Department of Dermato-Allergology; National Allergy Research Centre; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Pal B. Szecsi
- Department of Clinical Biochemistry; Copenhagen University Hospital Gentofte; Hellerup; Denmark
| | - Steen Stender
- Department of Clinical Biochemistry; Copenhagen University Hospital Gentofte; Hellerup; Denmark
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12
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Asai Y, Greenwood C, Hull PR, Alizadehfar R, Ben-Shoshan M, Brown SJ, Campbell L, Michel DL, Bussières J, Rousseau F, Fujiwara TM, Morgan K, Irvine AD, McLean WI, Clarke A. Filaggrin gene mutation associations with peanut allergy persist despite variations in peanut allergy diagnostic criteria or asthma status. J Allergy Clin Immunol 2013; 132:239-42. [PMID: 23684069 PMCID: PMC3919206 DOI: 10.1016/j.jaci.2013.03.043] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 02/19/2013] [Accepted: 03/28/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Yuka Asai
- Division of Dermatology, Department of Medicine, McGill University, Montreal, Quebec, Canada
- Division of Clinical Epidemiology, Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Celia Greenwood
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
- Department of Oncology and the Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada
| | - Peter R. Hull
- Division of Dermatology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Reza Alizadehfar
- Division of Allergy and Clinical Immunology, Department of Pediatrics, McGill University, Montreal, Quebec, Canada
| | - Moshe Ben-Shoshan
- Division of Allergy and Clinical Immunology, Department of Pediatrics, McGill University, Montreal, Quebec, Canada
| | | | | | - Deborah L. Michel
- Division of Dermatology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | | | | | - T. Mary Fujiwara
- Departments of Human Genetics and Medicine, McGill University, Montreal, Quebec, Canada
| | - Kenneth Morgan
- Departments of Human Genetics and Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | | | | | - Ann Clarke
- Division of Clinical Epidemiology, Department of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Division of Allergy/Clinical Immunology, Department of Medicine, McGill University, Montreal, Quebec, Canada
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13
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Abstract
Ichthyosis vulgaris is caused by loss-of-function mutations in the filaggrin gene (FLG) and is characterized clinically by xerosis, scaling, keratosis pilaris, palmar and plantar hyperlinearity, and a strong association with atopic disorders. According to the published studies presented in this review article, FLG mutations are observed in approximately 7·7% of Europeans and 3·0% of Asians, but appear to be infrequent in darker-skinned populations. This clinical review article provides an overview of ichthyosis vulgaris epidemiology, related disorders and pathomechanisms. Not only does ichthyosis vulgaris possess a wide clinical spectrum, recent studies suggest that carriers of FLG mutations may have a generally altered risk of developing common diseases, even beyond atopic disorders. Mechanistic studies have shown increased penetration of allergens and chemicals in filaggrin-deficient skin, and epidemiological studies have found higher levels of hand eczema, irritant contact dermatitis, nickel sensitization and serum vitamin D levels. When relevant, individuals should be informed about an increased risk of developing dermatitis when repeatedly or continuously exposed to nickel or irritants. Moreover, with our current knowledge, individuals with ichthyosis vulgaris should be protected against neonatal exposure to cats to prevent atopic dermatitis and should abstain from smoking to prevent asthma. Finally, they should be advised against excessive exposure to factors that decrease skin barrier functions and increase the risk of atopic dermatitis.
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Affiliation(s)
- J P Thyssen
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, UCSF, 4150 Clement Street, San Francisco, CA 94121, USA.
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Schmuth M, Martinz V, Janecke AR, Fauth C, Schossig A, Zschocke J, Gruber R. Inherited ichthyoses/generalized Mendelian disorders of cornification. Eur J Hum Genet 2013; 21:123-33. [PMID: 22739337 PMCID: PMC3548255 DOI: 10.1038/ejhg.2012.121] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 05/07/2012] [Accepted: 05/10/2012] [Indexed: 11/08/2022] Open
Abstract
Inherited ichthyoses, defined as the generalized form of Mendelian disorders of cornification, are characterized by visible scaling and/or hyperkeratosis of most or all of the skin. This etiologically and phenotypically heterogenous group of conditions is caused by mutations in various different genes important for keratinocyte differentiation and epidermal barrier function. Diagnosing a specific entity is a particular challenge for the nonspecialist presented with the common clinical scaling. For the clinician, this review outlines an algorithmic approach for utilizing diagnostic clues to narrow down the differential diagnosis and to guide further testing and treatment options.
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Affiliation(s)
- Matthias Schmuth
- Department of Dermatology and Venereology, Innsbruck Medical University, Innsbruck, Austria
| | - Verena Martinz
- Department of Dermatology and Venereology, Innsbruck Medical University, Innsbruck, Austria
| | - Andreas R Janecke
- Division of Human Genetics, Innsbruck Medical University, Innsbruck, Austria
- Department of Pediatrics II, Innsbruck Medical University, Innsbruck, Austria
| | - Christine Fauth
- Division of Human Genetics, Innsbruck Medical University, Innsbruck, Austria
| | - Anna Schossig
- Division of Human Genetics, Innsbruck Medical University, Innsbruck, Austria
| | - Johannes Zschocke
- Division of Human Genetics, Innsbruck Medical University, Innsbruck, Austria
| | - Robert Gruber
- Department of Dermatology and Venereology, Innsbruck Medical University, Innsbruck, Austria
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15
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Perusquía-Ortiz A, Oji V, Sauerland M, Tarinski T, Zaraeva I, Seller N, Metze D, Aufenvenne K, Hausser I, Traupe H. Complete filaggrin deficiency in ichthyosis vulgaris is associated with only moderate changes in epidermal permeability barrier function profile. J Eur Acad Dermatol Venereol 2013; 27:1552-8. [DOI: 10.1111/jdv.12079] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 11/21/2012] [Indexed: 11/28/2022]
Affiliation(s)
| | - V. Oji
- Department of Dermatology; University of Münster; Münster Germany
| | - M.C. Sauerland
- Institute of Biostatistics and Clinical Research; University of Münster; Münster Germany
| | - T. Tarinski
- Department of Dermatology; University of Münster; Münster Germany
| | - I. Zaraeva
- Department of Dermatology; University of Münster; Münster Germany
| | - N. Seller
- Department of Dermatology; University of Münster; Münster Germany
| | - D. Metze
- Department of Dermatology; University of Münster; Münster Germany
| | - K. Aufenvenne
- Department of Dermatology; University of Münster; Münster Germany
| | - I. Hausser
- Department of Dermatology; University of Heidelberg; Heidelberg Germany
| | - H. Traupe
- Department of Dermatology; University of Münster; Münster Germany
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Meldgaard M, Szecsi PB, Carlsen BC, Thyssen JP, Johansen JD, Menné T, Stender S. A novel multiplex analysis of filaggrin polymorphisms: a universally applicable method for genotyping. Clin Chim Acta 2012; 413:1488-92. [PMID: 22705401 DOI: 10.1016/j.cca.2012.06.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/24/2012] [Accepted: 06/07/2012] [Indexed: 11/25/2022]
Abstract
BACKGROUND The filaggrin protein is expressed as profilaggrin mainly in stratum granulosum cells of the epidermis. The profilaggrin gene codes for 10-12 filaggrin repeats. The filaggrin protein is important for skin barrier function. Filaggrin deficiency due to functional null-polymorphisms affects 8-10% of the people in Northern Europe and is a strong risk factor for several diseases. Here, we describe a novel method for efficient, multiplexed genotyping of variations in the profilaggrin gene. METHODS Five known techniques were combined: i) allele-specific PCR, ii) PCR with tagged primers, iii) asymmetric PCR, iv) multiplex PCR, and v) hybridization of single-stranded PCR products to spectrally coded microbeads carrying tag sequences as capture probes. Asymmetry of PCR was accomplished by having the tagged and allele-specific forward primers present in limiting concentrations. Asymmetry ensured that the later PCR cycles generated only single-stranded reverse-strand products. This greatly improved the assay sensitivity and allowed for simple optimization. RESULTS The specificity of the tags was verified with single PCR in wildtype and homozygous samples. Only the PCR products with the appropriate anti-tag hybridized to the corresponding beads, demonstrating the specificity of the signal. The hybridization signal is strongly dependent on single-stranded PCR products. After 46 PCR cycles, double-stranded products are clearly present, but only the single-stranded products generated in later cycles hybridize to the beads and elicit the strong signals that allow for unambiguous genotyping. CONCLUSIONS We have tested 17,000 samples for three filaggrin polymorphisms using this method, with a call rate exceeding 99% and a reagent cost of US $ 0.75 per sample. The method is universally applicable for multiplex genotyping of e.g. hereditary hemochromatosis, lactose intolerance, or cystic fibrosis.
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Affiliation(s)
- Michael Meldgaard
- Department of Clinical Biochemistry, Gentofte Hospital, University of Copenhagen, Denmark.
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17
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Xiong Z, Luo S, Xu X, Zhang L, Peng H, Li W, Xue J, Chen X, Hu Z, Xia K. Novel FLG mutations associated with ichthyosis vulgaris in the Chinese population. Clin Exp Dermatol 2012; 37:177-80. [DOI: 10.1111/j.1365-2230.2011.04229.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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18
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Gruber R, Elias PM, Crumrine D, Lin TK, Brandner JM, Hachem JP, Presland RB, Fleckman P, Janecke AR, Sandilands A, McLean WHI, Fritsch PO, Mildner M, Tschachler E, Schmuth M. Filaggrin genotype in ichthyosis vulgaris predicts abnormalities in epidermal structure and function. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 178:2252-63. [PMID: 21514438 DOI: 10.1016/j.ajpath.2011.01.053] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 01/13/2011] [Accepted: 01/25/2011] [Indexed: 12/16/2022]
Abstract
Although it is widely accepted that filaggrin (FLG) deficiency contributes to an abnormal barrier function in ichthyosis vulgaris and atopic dermatitis, the pathomechanism of how FLG deficiency provokes a barrier abnormality in humans is unknown. We report here that the presence of FLG mutations in Caucasians predicts dose-dependent alterations in epidermal permeability barrier function. Although FLG is an intracellular protein, the barrier abnormality occurred solely via a paracellular route in affected stratum corneum. Abnormal barrier function correlated with alterations in keratin filament organization (perinuclear retraction), impaired loading of lamellar body contents, followed by nonuniform extracellular distribution of secreted organelle contents, and abnormalities in lamellar bilayer architecture. In addition, we observed reductions in corneodesmosome density and tight junction protein expression. Thus, FLG deficiency provokes alterations in keratinocyte architecture that influence epidermal functions localizing to the extracellular matrix. These results clarify how FLG mutations impair epidermal permeability barrier function.
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Affiliation(s)
- Robert Gruber
- Department of Dermatology, Innsbruck Medical University, Innsbruck, Austria
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19
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Revised nomenclature and classification of inherited ichthyoses: results of the First Ichthyosis Consensus Conference in Sorèze 2009. J Am Acad Dermatol 2010; 63:607-41. [PMID: 20643494 DOI: 10.1016/j.jaad.2009.11.020] [Citation(s) in RCA: 454] [Impact Index Per Article: 32.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 10/30/2009] [Accepted: 11/17/2009] [Indexed: 12/21/2022]
Abstract
BACKGROUND Inherited ichthyoses belong to a large, clinically and etiologically heterogeneous group of mendelian disorders of cornification, typically involving the entire integument. Over the recent years, much progress has been made defining their molecular causes. However, there is no internationally accepted classification and terminology. OBJECTIVE We sought to establish a consensus for the nomenclature and classification of inherited ichthyoses. METHODS The classification project started at the First World Conference on Ichthyosis in 2007. A large international network of expert clinicians, skin pathologists, and geneticists entertained an interactive dialogue over 2 years, eventually leading to the First Ichthyosis Consensus Conference held in Sorèze, France, on January 23 and 24, 2009, where subcommittees on different issues proposed terminology that was debated until consensus was reached. RESULTS It was agreed that currently the nosology should remain clinically based. "Syndromic" versus "nonsyndromic" forms provide a useful major subdivision. Several clinical terms and controversial disease names have been redefined: eg, the group caused by keratin mutations is referred to by the umbrella term, "keratinopathic ichthyosis"-under which are included epidermolytic ichthyosis, superficial epidermolytic ichthyosis, and ichthyosis Curth-Macklin. "Autosomal recessive congenital ichthyosis" is proposed as an umbrella term for the harlequin ichthyosis, lamellar ichthyosis, and the congenital ichthyosiform erythroderma group. LIMITATIONS As more becomes known about these diseases in the future, modifications will be needed. CONCLUSION We have achieved an international consensus for the classification of inherited ichthyosis that should be useful for all clinicians and can serve as reference point for future research.
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Lower prevalence of common filaggrin mutations in a community sample of atopic eczema: is disease severity important? Wien Klin Wochenschr 2010; 122:551-7. [PMID: 20865458 DOI: 10.1007/s00508-010-1449-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 08/07/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Recent studies have shown an association of loss-of-function mutations in the filaggrin gene (FLG) with ichthyosis vulgaris and atopic eczema (AE). Case selection may have distorted the hitherto reported prevalence of FLG mutations and their relation to atopic disease. The aim of the study was to determine the true population prevalence of FLG mutations in unselected children with and without reported physician diagnoses of asthma, allergic rhinitis and AE and their relationship with family history of atopic disease. METHODS We used a nested case-control design by sampling children with reported doctor's diagnoses of AE, asthma and allergic rhinitis and randomly selected controls from a larger cross-sectional study (n = 1263). Most common FLG mutations R501X, 2282del4, and R2447X were screened in DNA extracted from defrosted urine samples. The relationship of the combined FLG variants with atopic diseases and with reported family history of AE, asthma, and rhinitis was assessed. RESULTS In the patient group one homozygote (R501X/R501X), 4 compound heterozygotes (3 R501X/2282del4, one 2282del4/R2447X), and 17 heterozygotes (10 R501X/wt, 5 2282del4/wt, and 2 R2447X/wt), in the control group 9 heterozygotes (5 R501X/wt, 4 2282del4/wt) were detected. The combined prevalence of FLG loss-of-function alleles was 5% in the control group and 9% in the atopic sample. In a subgroup analysis, the combination of allergic rhinitis and AE showed a significant relationship with FLG mutations, OR = 3.7 (1.01-12.67, p = 0.024). Likewise, significant relations with reported family history of asthma, OR = 4.35 (1.78-10.62, p = 0.0012), allergic rhinitis, OR = 2.33 (1.49-3.63, p = 0.0002), and AE, OR = 5.08 (2.78-9.30, p ≤ 0.0001) were observed. In contrast to clinical studies with higher percentages of severely affected persons, FLG mutations here showed a moderate association with atopic disease. CONCLUSIONS Case selection may be responsible for overestimating the prevalence of FLG mutations in atopic disease.
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Zhang X, Liu S, Chen X, Zhou B, Liu D, Lei G, Xiao X, Liu H, Wang H. Novel and recurrent mutations in the filaggrin gene in Chinese patients with ichthyosis vulgaris. Br J Dermatol 2010; 163:63-9. [PMID: 20222934 DOI: 10.1111/j.1365-2133.2010.09740.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Ichthyosis vulgaris (IV) is a common inherited skin disorder, and the filament aggregating protein (filaggrin) is a key protein involved in skin barrier function. Mutations in the filaggrin gene (FLG) have recently been identified as the cause of IV. However, there have been no reports of FLG mutations in mainland Chinese families with IV. OBJECTIVES To identify FLG mutations in Chinese patients with IV. METHODS Eleven unrelated Chinese families with IV were examined for FLG mutations with denaturing high-performance liquid chromatography prescreening and sequencing. SNaPShot was employed to obtain a high-throughput screening for the identified mutations. RESULTS Three mutations - one novel mutation (Q1256X) and two known mutations (3321delA and E2422X) - were identified in these families. The novel mutation, Q1256X, found in a Chinese family with IV, was located in filaggrin repeat 3. Mutation 3321delA, previously found in Japanese patients, was present in eight Chinese families with IV. Mutation E2422X, previously found in a Dutch patient of Chinese origin, was present in two Chinese families with IV. Neither of the null mutations, Q1256X and E2422X, were found in 100 unrelated control cases from the Chinese population; however, the mutation ratio for 3321delA was 3% in these controls. CONCLUSIONS Our study suggests that each population may have a unique and prevalent set of FLG mutations.
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Affiliation(s)
- X Zhang
- Laboratory of Genetics, West China Second University Hospital, Sichuan University, Chengdu 610041, China
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22
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Gruber R, Janecke AR, Grabher D, Sandilands A, Fauth C, Schmuth M. Evidence for genetic modifiers other than filaggrin mutations in X-linked ichthyosis. J Dermatol Sci 2010; 58:72-5. [PMID: 20149601 DOI: 10.1016/j.jdermsci.2010.01.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 11/04/2009] [Accepted: 01/14/2010] [Indexed: 02/07/2023]
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Burgess JA, Lowe AJ, Matheson MC, Varigos G, Abramson MJ, Dharmage SC. Does eczema lead to asthma? J Asthma 2009; 46:429-36. [PMID: 19544160 DOI: 10.1080/02770900902846356] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The nature of the relationship between eczema, asthma, and allergic rhinitis has been controversial. It has been commonly held that these disorders, while sharing genetic and environmental risk factors, are unrelated disorders that may develop sequentially along an atopic pathway. Conversely, the link between eczema and these later-onset respiratory disorders may be causal. This review examines the relationship between eczema, asthma, and allergic rhinitis in the context of the atopic march, the skin barrier, and recent developments in eczema genetics; and we propose that the relationship is causal. We describe a plausible biological pathway with eczema as the first step in a progressive atopic march that over time leads to asthma and/or allergic rhinitis. Such a pathway has implications for our understanding of these disorders and steps that might be made to prevent the development of asthma in particular. We propose that intervention studies in eczema should be conducted to confirm or refute this causal relationship. Such studies may materially improve the quality of life of eczema patients and will have important public health benefits if the interventions lead to a reduction in the burden of asthma.
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Affiliation(s)
- John A Burgess
- Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, The University of Melbourne, Carlton, Victoria, Australia.
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24
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Rodriguez S, Hall AJ, Granell R, McLean WHI, Irvine AD, Palmer CNA, Smith GD, Henderson J, Day INM. Carrier status for the common R501X and 2282del4 filaggrin mutations is not associated with hearing phenotypes in 5,377 children from the ALSPAC cohort. PLoS One 2009; 4:e5784. [PMID: 19492053 PMCID: PMC2685991 DOI: 10.1371/journal.pone.0005784] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Accepted: 05/08/2009] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Filaggrin is a major protein in the epidermis. Several mutations in the filaggrin gene (FLG) have been associated with a number of conditions. Filaggrin is expressed in the tympanic membrane and could alter its mechanical properties, but the relationship between genetic variation in FLG and hearing has not yet been tested. METHODOLOGY/PRINCIPAL FINDINGS We examined whether loss-of function mutations R501X and 2282del4 in the FLG gene affected hearing in children. Twenty eight hearing variables representing five different aspects of hearing at age nine years in 5,377 children from the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort were tested for association with these mutations. No evidence of association was found between R501X or 2282del4 (or overall FLG mutation carrier status) and any of the hearing phenotypes analysed. CONCLUSIONS/SIGNIFICANCE In conclusion, carrier status for common filaggrin mutations does not affect hearing in children.
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Affiliation(s)
- Santiago Rodriguez
- Bristol Genetic Epidemiology Laboratories (BGEL), Department of Social Medicine, University of Bristol, Bristol, UK.
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25
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Sinclair C, O’Toole E, Paige D, El Bashir H, Robinson J, Dobson R, Lench N, Stevens H, Hitman G, Booy R, Mein C, Kelsell D. Filaggrin mutations are associated with ichthyosis vulgaris in the Bangladeshi population. Br J Dermatol 2009; 160:1113-5. [DOI: 10.1111/j.1365-2133.2009.09050.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Oji V, Seller N, Sandilands A, Gruber R, Gerss J, Hüffmeier U, Hamm H, Emmert S, Aufenvenne K, Metze D, Luger T, Loser K, Hausser I, Traupe H, McLean WHI. Ichthyosis vulgaris: novel FLG mutations in the German population and high presence of CD1a+ cells in the epidermis of the atopic subgroup. Br J Dermatol 2009; 160:771-81. [PMID: 19183181 DOI: 10.1111/j.1365-2133.2008.08999.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Ichthyosis vulgaris (IV) is a genetic disorder with a prevalence of 1:250-1000 caused by filaggrin (FLG) mutations, which also predispose to atopic diseases. OBJECTIVES To study the genotype/phenotype relationship in IV and to analyse whether the suggested skin barrier defect is associated with differences of epidermal dendritic cells. PATIENTS/METHODS We evaluated a cohort of 26 German patients with IV, established an IV severity score and analysed epidermal ultrastructure, histology, filaggrin and CD1a antigens. Mutations were screened by restriction enzyme analysis. Particular sequencing techniques allowed the complete FLG analysis to reveal novel mutations. RESULTS The combined null allele frequency of R501X and 2282del4 was 67.3%. Patients also showed the mutations S3247X and R2447X as well as five novel FLG mutations: 424del17 and 621del4 (profilaggrin S100 domain), 2974delGA (repeat 2), R3766X (repeat 10(1)) and E4265X (repeat 10(2)). Their combined allele frequency in controls was <0.7%. No mutation was found in one IV patient, all in all approximately 27% were heterozygous, and the majority (approximately 69%) showed two null alleles. The IV severity score and ultrastructure showed a significant correlation with genotypes. Interestingly, CD1a cell counts showed a significant difference between nonatopic and atopic IV patients both with eczema and without eczema. CONCLUSIONS We confirm that the mutations R501X and 2282del4 represent the most frequent genetic cause in German IV patients. The novel mutations are probably population and family specific. The observed differences of CD1a cells support the hypothesis that there is a barrier defect that predisposes to atopic manifestations, possibly independent of atopic eczema.
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Affiliation(s)
- V Oji
- Department of Dermatology, University of Münster, Von-Esmarch-Str. 58, 48149 Münster, Germany.
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Abstract
The discovery that null mutations in the filaggrin gene (FLG) are associated with atopic eczema represents the single most significant breakthrough in understanding the genetic basis of this complex disorder. The association has been replicated in multiple independent studies during the past 2 years with the use of various methodologies, from populations in Europe, the United States, and Japan. Filaggrin plays a key role in epidermal barrier function, and its association with atopic eczema emphasizes the importance of barrier dysfunction in eczema pathogenesis. This review aims to summarize the current state of knowledge regarding the role of FLG mutations in ichthyosis vulgaris, atopic eczema, and other skin disorders, with an emphasis on potential clinical applications. Further research is needed to clarify the precise role of filaggrin in skin and systemic atopic disease, to pave the way for novel therapeutic interventions.
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The role of filaggrin loss-of-function mutations in atopic dermatitis. Curr Opin Allergy Clin Immunol 2008; 8:406-10. [PMID: 18769192 DOI: 10.1097/aci.0b013e32830e6fb2] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE OF REVIEW To provide a comprehensive summary of recent genetic advances as they relate to the pathogenesis of atopic dermatitis. RECENT FINDINGS Atopic dermatitis is a common inflammatory skin disease with a complex cause, resulting from an elaborate interplay between environmental, immunological and genetic factors. The disease is often the prelude to an atopic diathesis that includes asthma and other allergic diseases. The identification of mutations in the barrier protein filaggrin as conferring major susceptibility to atopic dermatitis and atopic dermatitis related asthma has reconfigured our understanding of disease mechanisms and highlights the importance of epidermal barrier disruption as a primary event in the disease. SUMMARY In this review we highlight recent advances in our understanding of how filaggrin might influence the environmental-immune interface, impacting disease penetrance, severity and trajectory, and the implications for both research and therapeutics in this field. Focusing on the downstream biological consequences of altered filaggrin expression and the sequence of immunological and environmental triggers that ensue will provide the rationale for targeted therapeutics capable of restoring or preventing disruption of barrier function.
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Sen GL, Webster DE, Barragan DI, Chang HY, Khavari PA. Control of differentiation in a self-renewing mammalian tissue by the histone demethylase JMJD3. Genes Dev 2008; 22:1865-70. [PMID: 18628393 DOI: 10.1101/gad.1673508] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The recent discovery of H3K27me3 demethylases suggests that H3K27me3 may dynamically regulate gene expression, but this potential role in mammalian tissue homeostasis remains uncharacterized. In the epidermis, a tissue that balances stem cell self-renewal with differentiation, H3K27me3, occupies the promoters of many differentiation genes. During calcium-induced differentiation, H3K27me3 was erased at these promoters in concert with loss of PcG protein occupancy and increased binding by the H3K27me3 demethylase, JMJD3. Within epidermal tissue, JMJD3 depletion blocked differentiation, while active JMJD3 dominantly induced it. These results indicate that epigenetic derepression by JMJD3 controls mammalian epidermal differentiation.
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Affiliation(s)
- George L Sen
- VA Palo Alto Health Care System, Palo Alto, California 94305, USA
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30
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[Mapping of pathogenic genes in two families with autosomal dominant ichthyosis vulgaris]. YI CHUAN = HEREDITAS 2008; 30:843-50. [PMID: 18779126 DOI: 10.3724/sp.j.1005.2008.00843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
To localize the pathogenic genes of autosomal dominant ichthyosis vulgaris, we ascertained two ichthyosis vulgaris families from Hunan Province. Venous blood samples were collected from affected and unaffected family members and genomic DNA was extracted. We then performed genome scan and linkage analysis using microsatellite markers around known ichthyosis vulgaris loci in chromosomes 1 and 10. In family 1, the locus linked to ichthyosis vulgaris was located near D1S498 (1q21), which overlapped with known ichthyosis vulgaris loci. In family 2, however, all known loci for ichthyosis vulgaris were excluded and the new locus remains to be identified.
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de Jongh CM, Khrenova L, Verberk MM, Calkoen F, van Dijk FJH, Voss H, John SM, Kezic S. Loss-of-function polymorphisms in the filaggrin gene are associated with an increased susceptibility to chronic irritant contact dermatitis: a case-control study. Br J Dermatol 2008; 159:621-7. [PMID: 18637008 DOI: 10.1111/j.1365-2133.2008.08730.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- C M de Jongh
- Coronel Institute of Occupational Health, Academic Medical Centre, University of Amsterdam, P.O. Box 22700, Amsterdam 1100 DE, the Netherlands
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32
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Unique and Recurrent Mutations in the Filaggrin Gene in Singaporean Chinese Patients with Ichthyosis Vulgaris. J Invest Dermatol 2008. [DOI: 10.1038/jid.2008.2] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Chen H, Ho JCC, Sandilands A, Chan YC, Giam YC, Evans AT, Lane EB, McLean WHI. Unique and recurrent mutations in the filaggrin gene in Singaporean Chinese patients with ichthyosis vulgaris. J Invest Dermatol 2008; 128:1669-75. [PMID: 18239616 DOI: 10.1038/sj.jid.2008.2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Filaggrin is an abundant protein of the outer epidermis that is essential for terminal differentiation of keratinocytes and formation of an effective barrier against water loss and pathogen/allergen/irritant invasion. Recent investigations in Europe and Japan have revealed null mutations in the filaggrin gene (FLG) as the underlying cause of ichthyosis vulgaris (IV), a common skin disorder characterised by dry skin, palmar hyperlinearity and keratosis pilaris. Following the development of a strategy for the comprehensive analysis of FLG, we have identified five unique mutations and one recurrent mutation in Singaporean Chinese IV patients. Mutation 441delA is located in the profilaggrin S100 domain, whereas two additional frameshift mutations, 1249insG and 7945delA, occur in the first partial filaggrin repeat ("repeat 0") and in filaggrin repeat 7, respectively. Both nonsense mutations Q2147X and E2422X are found in filaggrin repeat 6, whereas R4307X was found on one of the longer size variant alleles of FLG, within duplicated repeat 10.2. Mutation E2422X, previously found in a single Dutch patient, was found in one Singaporean IV patient and at a low frequency in Asian population controls. Our study confirms the presence of population-specific as well as recurrent FLG mutations in Singapore.
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Affiliation(s)
- Huijia Chen
- Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK
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34
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Rodríguez E, Illig T, Weidinger S. Filaggrin loss-of-function mutations and association with allergic diseases. Pharmacogenomics 2008; 9:399-413. [DOI: 10.2217/14622416.9.4.399] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Human skin constitutes a highly organized barrier against environmental agents. Its unrestricted function depends on a complex interplay between multiple proteins and lipids expressed in the terminally differentiating epithelium. Recently, attention has been drawn to the protein filaggrin, an integral part of the epidermis that plays a key role in engineering and maintaining the barrier function. Common loss-of-function mutations within the filaggrin gene have been demonstrated to cause ichthyosis vulgaris, one of the most common heritable disorders of cornification, and to represent major risk factors for atopic eczema and secondary allergic diseases. The observations on filaggrin provide striking new insights into the etiology of atopic diseases and might pave the way for the development of new therapeutic approaches.
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Affiliation(s)
- Elke Rodríguez
- Division of Environmental Dermatology and Allergy, Helmholtz Zentrum Muenchen, Neuherberg and ZAUM-Center for Allergy and Environment, Technical University Munich, Biedersteiner Str. 29, 80802 Munich, Germany
| | - Thomas Illig
- Institute of Epidemiology, Helmholtz Zentrum Muenchen, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Stephan Weidinger
- Department of Dermatology and Allergy, Technical University Munich, Biedersteiner Str. 29, 80802 Munich, Germany
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Schmuth M, Gruber R, Elias PM, Williams ML. Ichthyosis update: towards a function-driven model of pathogenesis of the disorders of cornification and the role of corneocyte proteins in these disorders. ACTA ACUST UNITED AC 2008; 23:231-56. [PMID: 18159904 DOI: 10.1016/j.yadr.2007.07.011] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Matthias Schmuth
- Department of Dermatology, University of California, VAMC Metabolism 111F, 4150 Clement Street, San Francisco, CA 94121, USA.
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36
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Audigier V, Shisha A, Jullien D. Génétique des altérations de la barrière cutanée dans la dermatite atopique. Ann Dermatol Venereol 2008; 135:34-7. [DOI: 10.1016/j.annder.2007.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Accepted: 11/14/2007] [Indexed: 11/30/2022]
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37
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The filaggrin story: novel insights into skin-barrier function and disease. Trends Mol Med 2007; 14:20-7. [PMID: 18068483 DOI: 10.1016/j.molmed.2007.10.006] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 10/24/2007] [Accepted: 10/30/2007] [Indexed: 11/20/2022]
Abstract
Recent reports have uncovered the key role of the protein filaggrin in maintaining an effective skin barrier against the external environment. Loss-of-function mutations in the profilaggrin gene (FLG) are common and are present in up to 10% of the population. These mutations are the cause of the semi-dominant skin-scaling disorder ichthyosis vulgaris and are a major risk factor for the development of atopic dermatitis. The discovery of these mutations also provides new data concerning the genetics of atopic asthma as well as intriguing insight into disease mechanisms of systemic allergies involving antigen exposure in skin with defective barrier function. Collectively, these novel findings have significant implications for the classification and future clinical management of patients with atopic and allergic diseases.
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38
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Baurecht H, Irvine AD, Novak N, Illig T, Bühler B, Ring J, Wagenpfeil S, Weidinger S. Toward a major risk factor for atopic eczema: Meta-analysis of filaggrin polymorphism data. J Allergy Clin Immunol 2007; 120:1406-12. [DOI: 10.1016/j.jaci.2007.08.067] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 08/29/2007] [Accepted: 08/31/2007] [Indexed: 10/22/2022]
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39
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Liao H, Waters AJ, Goudie DR, Aitken DA, Graham G, Smith FJD, Lewis-Jones S, McLean WHI. Filaggrin mutations are genetic modifying factors exacerbating X-linked ichthyosis. J Invest Dermatol 2007; 127:2795-8. [PMID: 17657246 DOI: 10.1038/sj.jid.5700971] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Mutations inactivating the STS gene cause X-linked ichthyosis (XLI), whereas null mutations in the FLG gene cause ichthyosis vulgaris. Two brothers presented with XLI. One had a typical fine scaling, and the other was much more severely affected. Both patients carried STS missense mutation T165I. Furthermore, the more severely affected patient also carried heterozygous FLG mutation R501X, which was absent from his mildly affected brother. These data suggest that disrupting epidermal differentiation via different pathways can increase phenotypic severity. Owing to the high population frequency of FLG mutations, filaggrin is a possible genetic modifier in other genodermatoses.
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Affiliation(s)
- Haihui Liao
- Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
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40
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Hoffjan S, Stemmler S. On the role of the epidermal differentiation complex in ichthyosis vulgaris, atopic dermatitis and psoriasis. Br J Dermatol 2007; 157:441-9. [PMID: 17573887 DOI: 10.1111/j.1365-2133.2007.07999.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Undisturbed epidermal differentiation is crucial for an intact skin barrier function. The epidermal differentiation complex (EDC) is a cluster of genes on chromosome 1q21 encoding proteins that fulfil important functions in terminal differentiation in the human epidermis, including filaggrin, loricrin, S100 proteins and others. Recently, evidence emerged that variation within EDC genes plays an important role in the pathogenesis of three common skin disorders, ichthyosis vulgaris, atopic dermatitis (AD) and psoriasis. Two loss-of-function mutations in the filaggrin (FLG) gene, R501X and 2282del4, were identified as causative for ichthyosis vulgaris in 15 affected European families, and the mode of inheritance was found to be semidominant. As ichthyosis vulgaris and AD often occur concomitantly in affected individuals, these two mutations were subsequently investigated in AD patients and found to be strongly associated with the disease. Following this first report, seven replication studies have been performed that all confirm an association of these two mutations with AD (or AD subtypes) in several European cohorts. Additionally, two unique loss-of-function mutations in the FLG gene were identified in Japanese ichthyosis vulgaris families and found to be associated with AD in a Japanese cohort. Thus, the FLG mutations are among the most consistently replicated associations for AD. Additionally, linkage analysis has suggested that variation within the EDC might also predispose for psoriasis but the exact susceptibility variation(s) have not yet been elucidated. Taken together, these findings convincingly demonstrate the important role of barrier dysfunction in various common skin disorders.
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Affiliation(s)
- S Hoffjan
- Department of Human Genetics, Ruhr-University, Universitätsstrasse 150, 44801 Bochum, Germany.
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41
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Sandilands A, Terron-Kwiatkowski A, Hull PR, O'Regan GM, Clayton TH, Watson RM, Carrick T, Evans AT, Liao H, Zhao Y, Campbell LE, Schmuth M, Gruber R, Janecke AR, Elias PM, van Steensel MAM, Nagtzaam I, van Geel M, Steijlen PM, Munro CS, Bradley DG, Palmer CNA, Smith FJD, McLean WHI, Irvine AD. Comprehensive analysis of the gene encoding filaggrin uncovers prevalent and rare mutations in ichthyosis vulgaris and atopic eczema. Nat Genet 2007; 39:650-4. [PMID: 17417636 DOI: 10.1038/ng2020] [Citation(s) in RCA: 457] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 03/07/2007] [Indexed: 02/07/2023]
Abstract
We recently reported two common filaggrin (FLG) null mutations that cause ichthyosis vulgaris and predispose to eczema and secondary allergic diseases. We show here that these common European mutations are ancestral variants carried on conserved haplotypes. To facilitate comprehensive analysis of other populations, we report a strategy for full sequencing of this large, highly repetitive gene, and we describe 15 variants, including seven that are prevalent. All the variants are either nonsense or frameshift mutations that, in representative cases, resulted in loss of filaggrin production in the epidermis. In an Irish case-control study, the five most common European mutations showed a strong association with moderate-to-severe childhood eczema (chi2 test: P = 2.12 x 10(-51); Fisher's exact test: heterozygote odds ratio (OR) = 7.44 (95% confidence interval (c.i.) = 4.9-11.3), and homozygote OR = 151 (95% c.i. = 20-1,136)). We found three additional rare null mutations in this case series, suggesting that the genetic architecture of filaggrin-related atopic dermatitis consists of both prevalent and rare risk alleles.
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Affiliation(s)
- Aileen Sandilands
- Epithelial Genetics Group, Human Genetics Unit, Division of Pathology and Neuroscience, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK
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