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González‐Del Carmen M, Montaño S, Reyes‐Hernández OD, Vizcaíno‐Dorado PA, Leyva‐García N, Morales‐Morfín JC, Diaz‐Beltran W, Quinto‐Santiago E, Cariño‐Calvo L, Magaña JJ, Leyva‐Gómez G, Cortés H. High prevalence of autosomal recessive congenital ichthyosis in a Mexican population caused by a new mutation in the
TGM1
gene: epidemiological evidence of a founder effect. Int J Dermatol 2020; 59:969-977. [DOI: 10.1111/ijd.14952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/19/2020] [Accepted: 04/24/2020] [Indexed: 12/12/2022]
Affiliation(s)
| | - Sarita Montaño
- Laboratorio de Modelado Molecular y Bioinformática Facultad de Ciencias Químico‐Biológicas Universidad Autónoma de Sinaloa Culiacán Sinaloa México
| | - Octavio D. Reyes‐Hernández
- Laboratorio de Biología Molecular del Cáncer UMIEZ Facultad de Estudios Superiores Zaragoza Universidad Nacional Autónoma de México Ciudad de México México
| | - Pablo A. Vizcaíno‐Dorado
- Laboratorio de Medicina Genómica Departamento de Genética Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra Ciudad de México México
| | - Norberto Leyva‐García
- Laboratorio de Medicina Genómica Departamento de Genética Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra Ciudad de México México
| | - Juan C. Morales‐Morfín
- Laboratorio de Medicina Genómica Departamento de Genética Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra Ciudad de México México
| | - Wendy Diaz‐Beltran
- Facultad de Medicina Universidad Veracruzana Ciudad Mendoza, Veracruz México
| | | | | | - Jonathan J. Magaña
- Laboratorio de Medicina Genómica Departamento de Genética Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra Ciudad de México México
| | - Gerardo Leyva‐Gómez
- Departamento de Farmacia Facultad de Química Universidad Nacional Autónoma de México Ciudad de México México
| | - Hernán Cortés
- Laboratorio de Medicina Genómica Departamento de Genética Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra Ciudad de México México
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Bueno E, Cañueto J, García-Patos V, Vicente MA, Bodet-Castillo D, Hernández-Ruíz ME, González-Sarmiento R. Novel mutations in FATP4 gene in two families with ichthyosis prematurity syndrome. J Eur Acad Dermatol Venereol 2016; 31:e11-e13. [PMID: 27168232 DOI: 10.1111/jdv.13584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- E Bueno
- Molecular Medicine Unit, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,IBSAL (Instituto de Investigación biomédica de Salamanca), University Hospital of Salamanca, Salamanca, Spain
| | - J Cañueto
- IBSAL (Instituto de Investigación biomédica de Salamanca), University Hospital of Salamanca, Salamanca, Spain.,Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
| | - V García-Patos
- Department of Dermatology, Hospital Vall d'Hebrón, Barcelona, Spain
| | - M Asunción Vicente
- Department of Dermatology, Hospital San Joan de Déu, Esplugues de Llobregat, Barcelona, Spain
| | - D Bodet-Castillo
- Department of Dermatology, Hospital Vall d'Hebrón, Barcelona, Spain
| | | | - R González-Sarmiento
- Molecular Medicine Unit, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,IBSAL (Instituto de Investigación biomédica de Salamanca), University Hospital of Salamanca, Salamanca, Spain
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3
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Al-Hassnan ZN, Al-Dosary M, Alfadhel M, Faqeih EA, Alsagob M, Kenana R, Almass R, Al-Harazi OS, Al-Hindi H, Malibari OI, Almutari FB, Tulbah S, Alhadeq F, Al-Sheddi T, Alamro R, AlAsmari A, Almuntashri M, Alshaalan H, Al-Mohanna FA, Colak D, Kaya N. ISCA2mutation causes infantile neurodegenerative mitochondrial disorder. J Med Genet 2014; 52:186-94. [DOI: 10.1136/jmedgenet-2014-102592] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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5
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Autosomal recessive congenital ichthyosis. ACTAS DERMO-SIFILIOGRAFICAS 2013; 104:270-84. [PMID: 23562412 DOI: 10.1016/j.adengl.2011.11.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 11/13/2011] [Indexed: 12/15/2022] Open
Abstract
The term autosomal recessive congenital ichthyosis (ARCI) refers to a group of rare disorders of keratinization classified as nonsyndromic forms of ichthyosis. This group was traditionally divided into lamellar ichthyosis (LI) and congenital ichthyosiform erythroderma (CIE) but today it also includes harlequin ichthyosis, self-healing collodion baby, acral self-healing collodion baby, and bathing suit ichthyosis. The combined prevalence of LI and CIE has been estimated at 1 case per 138 000 to 300 000 population. In some countries or regions, such as Norway and the coast of Galicia, the prevalence may be higher due to founder effects. ARCI is genetically highly heterogeneous and has been associated with 6 genes to date: TGM1, ALOXE3, ALOX12B, NIPAL4, CYP4F22, and ABCA12. In this article, we review the current knowledge on ARCI, with a focus on clinical, histological, ultrastructural, genetic, molecular, and treatment-related aspects.
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6
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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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8
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Alzahrani AS, Zou M, Baitei EY, Parhar RS, Al-Kahtani N, Raef H, Almahfouz A, Amartey JK, Al-Rijjal R, Hammami R, Meyer BF, Al-Mohanna FA, Shi Y. Molecular characterization of a novel p.R118C mutation in the insulin receptor gene from patients with severe insulin resistance. Clin Endocrinol (Oxf) 2012; 76:540-7. [PMID: 22017372 DOI: 10.1111/j.1365-2265.2011.04258.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
CONTEXT Mutations of the insulin receptor gene (INSR) can cause genetic syndromes associated with severe insulin resistance. OBJECTIVES We aimed to analyse INSR mutations in Saudi patients with severe insulin resistance. DESIGN Ten patients with Type A insulin resistance syndrome from five unrelated Saudi families were investigated. The entire coding region of INSR was sequenced. The founder effect was assessed by microsatellite haplotype analysis. The functional effect of the mutation was investigated by in vitro functional assays. RESULTS A novel biallelic c.433 C>T (p.R118C) mutation was detected in all patients. The c.433 C>T (p.R118C) sequence variation was not found in 100 population controls. The arginine residue at position 118 is located in the ligand-binding domain of INSR and is highly conserved across species. Microsatellite haplotype analysis of these patients indicated that p.R118C was a founder mutation created approximately 2900 years ago. The wild-type and mutant (R118C) INSR were cloned and expressed in CHO cells for functional analysis. Specific insulin binding to the mutant receptor was reduced by 83% as compared to wild-type (WT), although the mutant receptor was processed and expressed on the cell surface. Insulin-mediated receptor autophosphorylation was also significantly reduced in CHO(R118C) cells. CONCLUSIONS Biallelic c.433 C>T (p.R118C) mutation of INSR causes significant damage to insulin binding and insulin-mediated signal transduction. p.R118C is a founder mutation frequently present in the Saudi patients with severe insulin resistance.
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Affiliation(s)
- Ali S Alzahrani
- Department of Medicine, King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia
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9
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Dahlqvist J, Westermark GT, Vahlquist A, Dahl N. Ichthyin/NIPAL4 localizes to keratins and desmosomes in epidermis and Ichthyin mutations affect epidermal lipid metabolism. Arch Dermatol Res 2012; 304:377-86. [PMID: 22258272 DOI: 10.1007/s00403-012-1207-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Revised: 01/01/2012] [Accepted: 01/05/2012] [Indexed: 11/29/2022]
Abstract
Autosomal recessive congenital ichthyosis (ARCI) is a group of disorders characterized by abnormal desquamation of the skin and a disrupted epidermal water barrier. Ichthyin/NIPAL4 gene mutations have been identified in a subgroup of ARCI patients, but the role of ichthyin in epidermis remains elusive. In order to obtain new insights concerning the characteristics of ichthyin and the ARCI pathogenesis, we studied the expression and localization of ichthyin and related epidermal components in cultured keratinocytes and skin sections from patients with Ichthyin mutations and healthy controls. We observed an up-regulation of Ichthyin mRNA levels after in vitro differentiation of keratinocytes from both a patient with Ichthyin mutations and controls. Confocal and electron microscopy analyses of immunolabeled skin sections revealed that ichthyin localizes to desmosomes and keratins in both patients with mutant Ichthyin and controls, with an increased immunolabeling in patients. Nile red lipid analysis of skin sections exposed intra-cellular lipid accumulations in cells of the granular and cornified layers in patients but not in controls, consistent with the pathognomonic lipid membrane structures previously identified in epidermis from patients. Our combined findings indicate that ichthyin is associated with keratins and desmosomes in epidermis and is involved in lipid metabolism, possibly through processing of lamellar bodies. These results provide new clues to the understanding of the epidermal water barrier and the pathogenesis in ARCI.
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Affiliation(s)
- Johanna Dahlqvist
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, 75185, Uppsala, Sweden
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10
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Dahlqvist J, Törmä H, Badhai J, Dahl N. siRNA silencing of proteasome maturation protein (POMP) activates the unfolded protein response and constitutes a model for KLICK genodermatosis. PLoS One 2012; 7:e29471. [PMID: 22235297 PMCID: PMC3250448 DOI: 10.1371/journal.pone.0029471] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 11/29/2011] [Indexed: 12/29/2022] Open
Abstract
Keratosis linearis with ichthyosis congenita and keratoderma (KLICK) is an autosomal recessive skin disorder associated with a single-nucleotide deletion in the 5′untranslated region of the proteasome maturation protein (POMP) gene. The deletion causes a relative switch in transcription start sites for POMP, predicted to decrease levels of POMP protein in terminally differentiated keratinocytes. To investigate the pathophysiology behind KLICK we created an in vitro model of the disease using siRNA silencing of POMP in epidermal air-liquid cultures. Immunohistochemical analysis of the tissue constructs revealed aberrant staining of POMP, proteasome subunits and the skin differentiation marker filaggrin when compared to control tissue constructs. The staining patterns of POMP siRNA tissue constructs showed strong resemblance to those observed in skin biopsies from KLICK patients. Western blot analysis of lysates from the organotypic tissue constructs revealed an aberrant processing of profilaggrin to filaggrin in samples transfected with siRNA against POMP. Knock-down of POMP expression in regular cell cultures resulted in decreased amounts of proteasome subunits. Prolonged silencing of POMP in cultured cells induced C/EBP homologous protein (CHOP) expression consistent with an activation of the unfolded protein response and increased endoplasmic reticulum (ER) stress. The combined results indicate that KLICK is caused by reduced levels of POMP, leading to proteasome insufficiency in differentiating keratinocytes. Proteasome insufficiency disturbs terminal epidermal differentiation, presumably by increased ER stress, and leads to perturbed processing of profilaggrin. Our findings underline a critical role for the proteasome in human epidermal differentiation.
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Affiliation(s)
- Johanna Dahlqvist
- Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Hans Törmä
- Department of Medical Sciences, Uppsala University and University Hospital, Uppsala, Sweden
| | - Jitendra Badhai
- Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Niklas Dahl
- Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- * E-mail:
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11
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Khnykin D, Miner JH, Jahnsen F. Role of fatty acid transporters in epidermis: Implications for health and disease. DERMATO-ENDOCRINOLOGY 2011; 3:53-61. [PMID: 21695012 PMCID: PMC3117002 DOI: 10.4161/derm.3.2.14816] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 01/07/2011] [Accepted: 01/13/2011] [Indexed: 12/31/2022]
Abstract
Skin epidermis is an active site of lipid synthesis. The intercellular lipids of human stratum corneum (SC) are unique in composition and quite different from the lipids found in most biological membranes. The three major lipids in the SC are free fatty acids, cholesterol and ceramides. Fatty acids can be synthesized by keratinocytes de novo and, in addition, need to be taken up from the circulation. The latter process has been shown to be protein mediated, and several fatty acid transporters are expressed in skin. Recent studies of transgenic and knockout animal models for fatty acid transporters and the identification of fatty acid transport protein 4 (FATP4 or SLC27A4) mutations as causative for Ichthyosis Prematurity Syndrome highlight the vital roles of fatty acid transport and metabolism in skin homeostasis. This review provides an overview of our current understanding of the role of fatty acids and their transporters in cutaneous biology, including their involvement in epidermal barrier generation and skin inflammation.
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Affiliation(s)
- Denis Khnykin
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT); Department of Pathology; Oslo University Hospital-Rikshospitalet; Oslo, Norway
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12
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Morice-Picard F, Léauté-Labrèze C, Décor A, Boralevi F, Lacombe D, Taieb A, Fischer J. A novel mutation in the fatty acid transport protein 4 gene in a patient initially described as affected by self-healing congenital verruciform hyperkeratosis. Am J Med Genet A 2010; 152A:2664-5. [DOI: 10.1002/ajmg.a.33648] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Klar J, Schweiger M, Zimmerman R, Zechner R, Li H, Törmä H, Vahlquist A, Bouadjar B, Dahl N, Fischer J. Mutations in the fatty acid transport protein 4 gene cause the ichthyosis prematurity syndrome. Am J Hum Genet 2009; 85:248-53. [PMID: 19631310 PMCID: PMC2725242 DOI: 10.1016/j.ajhg.2009.06.021] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Revised: 06/23/2009] [Accepted: 06/24/2009] [Indexed: 12/01/2022] Open
Abstract
Ichthyosis prematurity syndrome (IPS) is an autosomal-recessive disorder characterized by premature birth and neonatal asphyxia, followed by a lifelong nonscaly ichthyosis with atopic manifestations. Here we show that the gene encoding the fatty acid transport protein 4 (FATP4) is mutated in individuals with IPS. Fibroblasts derived from a patient with IPS show reduced activity of very long-chain fatty acids (VLCFA)-CoA synthetase and a specific reduction in the incorporation of VLCFA into cellular lipids. The human phenotype is consistent with Fatp4 deficiency in mice that is characterized by a severe skin phenotype, a defective permeability barrier function, and perturbed VLCFA metabolism. Our results further emphasize the importance of fatty acid metabolism for normal epidermal barrier function illustrated by deficiency of a member in the FATP family of proteins.
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Affiliation(s)
- Joakim Klar
- Department of Genetics and Pathology, Uppsala University, 75185 Uppsala, Sweden
| | - Martina Schweiger
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Robert Zimmerman
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria
| | - Hao Li
- Department of Medical Sciences, Uppsala University Hospital, 75185 Uppsala, Sweden
| | - Hans Törmä
- Department of Medical Sciences, Uppsala University Hospital, 75185 Uppsala, Sweden
| | - Anders Vahlquist
- Department of Medical Sciences, Uppsala University Hospital, 75185 Uppsala, Sweden
| | - Bakar Bouadjar
- Department of Dermatology, CHU of Bab-El-Oued, 16000 Algiers, Algeria
| | - Niklas Dahl
- Department of Genetics and Pathology, Uppsala University, 75185 Uppsala, Sweden
| | - Judith Fischer
- CEA, Institut de Génomique, CNG, 91057 Evry Cedex, France
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de Juanes S, Epp N, Latzko S, Neumann M, Fürstenberger G, Hausser I, Stark HJ, Krieg P. Development of an ichthyosiform phenotype in Alox12b-deficient mouse skin transplants. J Invest Dermatol 2009; 129:1429-36. [PMID: 19122646 DOI: 10.1038/jid.2008.410] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
12R-lipoxygenase (12R-LOX) represents a key enzyme of a recently identified eicosanoid pathway in the skin that plays an essential role in the establishment and/or maintenance of the epidermal barrier function. Genetic studies show that loss-of-function mutations in ALOX12B, encoding 12R-LOX, and in ALOXE3, encoding another closely related LOX involved in this pathway, are the second most common cause for autosomal recessive congenital ichthyosis (ARCI). To investigate the pathomechanism of ARCI and the function of 12R-LOX, we recently generated a 12R-LOX knockout model. 12R-LOX-deficient mice die rapidly after birth from severe barrier dysfunction without exhibiting an obvious cutaneous phenotype. Thus, we analyzed the adult phenotype of 12R-LOX(-/-) skin transplanted onto nude mice. 12R-LOX(-/-) skin develops an ichthyosiform appearance with thickening of the epidermis, hyperproliferation, hypergranulosis, focal parakeratosis, and severe hyperkeratosis. The adult mutant mouse skin phenotype closely reproduces the ichthyosis phenotype seen in patients with ALOX12B mutations. Western blot analysis revealed restoration of profilaggrin processing that used to be disturbed in neonatal mutant skin and overexpression of filaggrin, involucrin, and repetin. The results indicate that 12R-LOX knockout mice may represent a useful animal model for a detailed analysis of mechanisms involved in ARCI forms that are associated with impaired LOX metabolism.
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Affiliation(s)
- Silvia de Juanes
- Genome Modifications and Carcinogenesis, German Cancer Research Center, Heidelberg, Germany
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15
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Bygum A, Westermark P, Brandrup F. Ichthyosis prematurity syndrome: A well-defined congenital ichthyosis subtype. J Am Acad Dermatol 2008; 59:S71-4. [DOI: 10.1016/j.jaad.2008.06.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 06/12/2008] [Accepted: 06/13/2008] [Indexed: 10/21/2022]
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16
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Dahlqvist J, Klar J, Hausser I, Anton-Lamprecht I, Pigg MH, Gedde-Dahl T, Gånemo A, Vahlquist A, Dahl N. Congenital ichthyosis: mutations in ichthyin are associated with specific structural abnormalities in the granular layer of epidermis. J Med Genet 2007; 44:615-20. [PMID: 17557927 PMCID: PMC2597970 DOI: 10.1136/jmg.2007.050542] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Autosomal recessive congenital ichthyosis (ARCI) is a heterogeneous group of skin disorders. Several mutant genes have been identified in ARCI, but the association between genotype and phenotype is poorly understood. METHODS To investigate genotype-phenotype correlations in ARCI, we selected 27 patients from 18 families with specific ultrastructural features of the epidermis. The characteristic findings using electron microscopy (EM) were abnormal lamellar bodies and elongated membranes in the stratum granulosum, classified as ARCI EM type III. DNA samples from a subset of affected individuals were screened for homozygous genomic regions, and a candidate gene region was identified on chromosome 5q33. The region coincides with the ichthyin gene, previously reported as mutated in ARCI. RESULTS Mutation screening of ichthyin revealed missense or splice-site mutations in affected members from 16 of 18 (89%) families with characteristics of ARCI EM type III. In a control group of 18 patients with ARCI without EM findings consistent with type III, we identified one patient homozygous for a missense mutation in ichthyin. DISCUSSION Our findings indicate a strong association between ultrastructural abnormalities in the granular layer of epidermis and ichthyin mutations. The results also suggest that EM provides a tool for specific diagnosis in a genetically homogenous subgroup of patients with ARCI.
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Affiliation(s)
- J Dahlqvist
- Department of Genetics and Pathology, Uppsala University, The Rudbeck Laboratory, Uppsala, Sweden
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17
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Melin M, Entesarian M, Carlsson G, Garwicz D, Klein C, Fadeel B, Nordenskjöld M, Palmblad J, Henter JI, Dahl N. Assignment of the gene locus for severe congenital neutropenia to chromosome 1q22 in the original Kostmann family from Northern Sweden. Biochem Biophys Res Commun 2006; 353:571-5. [PMID: 17188649 PMCID: PMC2721957 DOI: 10.1016/j.bbrc.2006.12.086] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Accepted: 12/06/2006] [Indexed: 11/25/2022]
Abstract
Autosomal recessive severe congenital neutropenia (SCN) or Kostmann syndrome is characterised by reduced neutrophil counts and subsequent recurrent bacterial infections. The disease was originally described in a large consanguineous pedigree from Northern Sweden. A genome-wide autozygosity scan was initiated on samples from four individuals in the original pedigree using high density single nucleotide polymorphism (SNP) genotyping arrays in order to map the disease locus. Thirty candidate regions were identified and the ascertainment of samples from two additional patients confirmed a single haplotype with significant association to the disorder (p<0.01) on chromosome 1q22. One affected individual from the original Kostmann pedigree was confirmed as a phenocopy. The minimal haplotype shared by affected individuals spans a candidate region of 1.2 Mb, containing several potential candidate genes.
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Affiliation(s)
- M Melin
- Department of Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - M Entesarian
- Department of Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - G Carlsson
- Department of Woman and Child Health, Karolinska Hospital, Stockholm, Sweden
| | - D Garwicz
- Department of Molecular Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - C Klein
- Department of Pediatric Haematology/Oncology, Hannover Medical School, Hannover, Germany
| | - B Fadeel
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - M Nordenskjöld
- Department of Molecular Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - J Palmblad
- Department of Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - JI Henter
- Department of Woman and Child Health, Karolinska Hospital, Stockholm, Sweden
| | - N Dahl
- Department of Genetics and Pathology, The Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
- Corresponding author. Fax: +46-18-554025. E-mail address: (N. Dahl)
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