1
|
Terrinoni A, Sala G, Bruno E, Pitolli C, Minieri M, Pieri M, Gambacurta A, Campione E, Belardi R, Bernardini S. Partial Loss of Function ABCA12 Mutations Generate Reduced Deposition of Glucosyl-Ceramide, Leading to Patchy Ichthyosis and Erythrodermia Resembling Erythrokeratodermia Variabilis et Progressiva (EKVP). Int J Mol Sci 2023; 24:13962. [PMID: 37762265 PMCID: PMC10530436 DOI: 10.3390/ijms241813962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/25/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
Ichthyoses are genetically determined cornification disorders of the epidermis characterized by the presence of different degrees of scaling, hyperkeratosis, and erythroderma often associated with palmoplantar keratoderma. Different classifications of these diseases have been proposed, often based upon the involved genes and/or the clinical presentation. The clinical features of these diseases present some overlap of phenotypes among distinct genetic entities, depending mainly on the penetrance of mutations. In this study, using a clinical, genetic, and molecular approach, we analyzed a family with two affected members who had clinical and histological features resembling erythrokeratodermia variabilis (EKV) or a type of erythrodermic hyperkeratosis with palmoplantar keratoderma. Despite of the clinical presentation, we demonstrated that the affected patients were genetically double heterozygous for two different mutations in the ABCA12 gene, known to be responsible for harlequin ichthyosis. To explain the mild phenotype of our patients, we performed a molecular characterization of the skin. In the upper layers of the epidermis, the results showed a patchy presence of the glucosyl-ceramides (GlcCer), which is the lipid transported by ABCA12, fundamental in contributing to skin impermeability. Indeed, the two mutations detected do not completely abolish ABCA12 activity, indicating that the mild phenotype is due to a partial loss of function of the enzyme, thus giving rise to an intermediate phenotype resembling EKVP, due to a partial depletion of GlcCer deposition.
Collapse
Affiliation(s)
- Alessandro Terrinoni
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Gabriele Sala
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Ernesto Bruno
- Department of Clinical Sciences and Translational Medicine University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy;
| | - Consuelo Pitolli
- Department of Neuroscience, Section of Human Anatomy, Catholic University of the Sacred Heart, Largo Francesco Vito 1, 00168 Rome, Italy;
| | - Marilena Minieri
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Massimo Pieri
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Alessandra Gambacurta
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Elena Campione
- Department of System Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy;
| | - Riccardo Belardi
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| | - Sergio Bernardini
- Department of Experimental Medicine, University of Tor Vergata, Via Montpellier 1, 00133 Rome, Italy; (G.S.); (M.M.); (M.P.); (A.G.); (R.B.); (S.B.)
| |
Collapse
|
2
|
Gutiérrez-Cerrajero C, Sprecher E, Paller AS, Akiyama M, Mazereeuw-Hautier J, Hernández-Martín A, González-Sarmiento R. Ichthyosis. Nat Rev Dis Primers 2023; 9:2. [PMID: 36658199 DOI: 10.1038/s41572-022-00412-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/02/2022] [Indexed: 01/20/2023]
Abstract
The ichthyoses are a large, heterogeneous group of skin cornification disorders. They can be inherited or acquired, and result in defective keratinocyte differentiation and abnormal epidermal barrier formation. The resultant skin barrier dysfunction leads to increased transepidermal water loss and inflammation. Disordered cornification is clinically characterized by skin scaling with various degrees of thickening, desquamation (peeling) and erythema (redness). Regardless of the type of ichthyosis, many patients suffer from itching, recurrent infections, sweating impairment (hypohidrosis) with heat intolerance, and diverse ocular, hearing and nutritional complications that should be monitored periodically. The characteristic clinical features are considered to be a homeostatic attempt to repair the skin barrier, but heterogeneous clinical presentation and imperfect phenotype-genotype correlation hinder diagnosis. An accurate molecular diagnosis is, however, crucial for predicting prognosis and providing appropriate genetic counselling. Most ichthyoses severely affect patient quality of life and, in severe forms, may cause considerable disability and even death. So far, treatment provides only symptomatic relief. It is lifelong, expensive, time-consuming, and often provides disappointing results. A better understanding of the molecular mechanisms that underlie these conditions is essential for designing pathogenesis-driven and patient-tailored innovative therapeutic solutions.
Collapse
Affiliation(s)
- Carlos Gutiérrez-Cerrajero
- Department of Medicine, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,Biomedical Research Institute of Salamanca (IBSAL), Salamanca, Spain
| | - Eli Sprecher
- Division of Dermatology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amy S Paller
- Departments of Dermatology and Paediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Masashi Akiyama
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | | | | | - Rogelio González-Sarmiento
- Department of Medicine, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,Biomedical Research Institute of Salamanca (IBSAL), Salamanca, Spain
| |
Collapse
|
3
|
Matyas M, Miclea D, Zaharie G. Case Report: Uncommon Association of ITGB4 and KRT10 Gene Mutation in a Case of Epidermolysis Bullosa With Pyloric Atresia and Aplasia Cutis Congenita. Front Genet 2021; 12:641977. [PMID: 34306001 PMCID: PMC8296908 DOI: 10.3389/fgene.2021.641977] [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: 02/16/2021] [Accepted: 06/07/2021] [Indexed: 11/29/2022] Open
Abstract
Background: Epidermolysis bullosa is a rare form of genodermatosis produced by different gene mutations. The junctional form of the disease (JEB-PA) can associate pyloric atresia, renal abnormalities, and aplasia cutis congenita. Case Description: A case of a male preterm newborn with suspicion of digestive tube malformation at fetal ultrasound and who was born by cesarian section. At birth, he presented extensive cutaneous aplasia on the lower limbs and bilaterally under ears; outer ear agenesis; nasal septum hypoplasia; micrognathia; multiple blisters on the face, trunk, and limbs; lower limb deformities and absence of toe nails. Pathological examination following a surgical procedure with unfavorable outcome showed pyloric atresia, junctional form of epidermolysis bullosa and aplasia cutis congenita. Homozygous variants in two genes were identified: c.3111+1G>A in ITGB4 (class 5) and c.1498G>T in KRT10 (class 3). Conclusion: The particularity of our case is the novel finding of a coincidental occurrence in the context of consaguinity of two mutations in the ITGB4 and KRT10 genes, and clinical characteristics of epidermolysis bullosa.
Collapse
Affiliation(s)
- Melinda Matyas
- Neonatology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Diana Miclea
- Genetics, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Gabriela Zaharie
- Neonatology, Iuliu Haţieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| |
Collapse
|
4
|
Deng Z, Cangkrama M, Butt T, Jane SM, Carpinelli MR. Grainyhead-like transcription factors: guardians of the skin barrier. Vet Dermatol 2021; 32:553-e152. [PMID: 33843098 DOI: 10.1111/vde.12956] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/24/2020] [Accepted: 12/14/2020] [Indexed: 01/02/2023]
Abstract
There has been selective pressure to maintain a skin barrier since terrestrial animals evolved 360 million years ago. These animals acquired an unique integumentary system with a keratinized, stratified, squamous epithelium surface barrier. The barrier protects against dehydration and entry of microbes and toxins. The skin barrier centres on the stratum corneum layer of the epidermis and consists of cornified envelopes cemented by the intercorneocyte lipid matrix. Multiple components of the barrier undergo cross-linking by transglutaminase (TGM) enzymes, while keratins provide additional mechanical strength. Cellular tight junctions also are crucial for barrier integrity. The grainyhead-like (GRHL) transcription factors regulate the formation and maintenance of the integument in diverse species. GRHL3 is essential for formation of the skin barrier during embryonic development, whereas GRHL1 maintains the skin barrier postnatally. This is achieved by transactivation of Tgm1 and Tgm5, respectively. In addition to its barrier function, GRHL3 plays key roles in wound repair and as an epidermal tumour suppressor. In its former role, GRHL3 activates the planar cell polarity signalling pathway to mediate wound healing by providing directional migration cues. In squamous epithelium, GRHL3 regulates the balance between proliferation and differentiation, and its loss induces squamous cell carcinoma (SCC). In the skin, this is mediated through increased expression of MIR21, which reduces the expression levels of GRHL3 and its direct target, PTEN, leading to activation of the PI3K-AKT signalling pathway. These data position the GRHL family as master regulators of epidermal homeostasis across a vast gulf of evolutionary history.
Collapse
Affiliation(s)
- Zihao Deng
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Michael Cangkrama
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Tariq Butt
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Stephen M Jane
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Marina R Carpinelli
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| |
Collapse
|
5
|
Samuelov L, Sarig O, Adir N, Pavlovsky M, Smith FJ, Schwartz J, Hansen CD, Sprecher E. Identification of clinically useful predictive genetic variants in pachyonychia congenita. Clin Exp Dermatol 2021; 46:867-873. [PMID: 33486795 DOI: 10.1111/ced.14569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/19/2020] [Accepted: 01/21/2021] [Indexed: 10/22/2022]
Abstract
BACKGROUND Pachyonychia congenita (PC) refers to a group of autosomal dominant disorders caused by mutations in five keratin genes (KRT16,KRT6A,KRT17,KRT6B or KRT6C). Current disease classification is based on the gene harbouring disease-causing variants. AIMS We harnessed the International Pachyonychia Congenita Research Registry (IPCRR) containing both clinical and molecular data on patients with PC worldwide, to identify genetic variants predicting disease severity. METHODS We ascertained 815 individuals harbouring keratin mutations registered in the IPCRR. We looked for statistically significant associations between genetic variants and clinical manifestations in a subgroup of patients carrying mutations found in at least 10% of the cohort. Data were analysed using χ2 and Kruskal-Wallis tests. RESULTS We identified five mutations occurring in at least 10% of the patients registered in the IPCRR. The KRT16 p.L132P mutation was significantly associated with younger age of onset, presence of palmar keratoderma oral leucokeratosis and a higher number of involved nails. By contrast, the KRT16 p.N125S and p.R127C mutations resulted in a milder phenotype featuring a decreased number of involved nails and older age of onset. Patients carrying the p.N125S mutation were less likely to develop palmar keratoderma while p.R127C was associated with an older age of palmoplantar keratoderma onset. Moreover, the KRT17 p.L99P mutation resulted in an increased number of involved fingernails and patients demonstrating 20-nail dystrophy, while the opposite findings were observed with KRT17 p.N92S mutation. CONCLUSIONS We have identified novel and clinically useful genetic predictive variants in the largest cohort of patients with PC described to date.
Collapse
Affiliation(s)
- L Samuelov
- Division of Dermatology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - O Sarig
- Division of Dermatology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - N Adir
- Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa, Israel
| | - M Pavlovsky
- Division of Dermatology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - F J Smith
- Pachyonychia Congenita Project, Holladay, UT, USA
| | - J Schwartz
- Pachyonychia Congenita Project, Holladay, UT, USA
| | - C D Hansen
- Pachyonychia Congenita Project, Holladay, UT, USA.,Department of Dermatology, University of Utah, Salt Lake City, UT, USA
| | - E Sprecher
- Division of Dermatology, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| |
Collapse
|
6
|
Visualization of Keratin with Diffuse Reflectance and Autofluorescence Imaging and Nonlinear Optical Microscopy in a Rare Keratinopathic Ichthyosis. SENSORS 2021; 21:s21041105. [PMID: 33562614 PMCID: PMC7915665 DOI: 10.3390/s21041105] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/22/2021] [Accepted: 02/02/2021] [Indexed: 01/23/2023]
Abstract
Keratins are one of the main fluorophores of the skin. Keratinization disorders can lead to alterations in the optical properties of the skin. We set out to investigate a rare form of keratinopathic ichthyosis caused by KRT1 mutation with two different optical imaging methods. We used a newly developed light emitting diode (LED) based device to analyze autofluorescence signal at 405 nm excitation and diffuse reflectance at 526 nm in vivo. Mean autofluorescence intensity of the hyperkeratotic palmar skin was markedly higher in comparison to the healthy control (162.35 vs. 51.14). To further assess the skin status, we examined samples from affected skin areas ex vivo by nonlinear optical microscopy. Two-photon excited fluorescence and second-harmonic generation can visualize epidermal keratin and dermal collagen, respectively. We were able to visualize the structure of the epidermis and other skin changes caused by abnormal keratin formation. Taken together, we were able to show that such imaging modalities are useful for the diagnosis and follow-up of keratinopathic diseases.
Collapse
|
7
|
Chen L, Quan C, Zheng J, Pan M, Zhao X. A Case of Annular Epidermolytic Ichthyosis Resulting from a de Novo Mutation, p.I479T, in Keratin 1 Gene. Indian J Dermatol 2021; 66:224. [PMID: 34188299 PMCID: PMC8208282 DOI: 10.4103/ijd.ijd_115_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
We report a case of annular epidermolytic ichthyosis (AEI) resulting from de novo keratin 1 gene mutation. AEI is a rare autosomal dominantly inherited cornification disorder and is a distinct phenotypic variant of bullous congenital ichthyosiform erythroderma. Blisters and erosions in AEI are widespread; hence, initially, it is sometimes mistaken with epidermolysis bullosa, acrodermatitis enteropathica, and staphylococcal scalded skin syndrome. Genetic tests including next-generation sequencing and Sanger sequencing are essential for AEI diagnosis. AEI is treated symptomatically by wound dressing, prevention of infection, and the use of emollients, humectants, and keratolytic products; topical or systemic retinoids may also prove helpful.
Collapse
Affiliation(s)
- Lihong Chen
- Department of Dermatology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Cheng Quan
- Department of Dermatology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jie Zheng
- Department of Dermatology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Meng Pan
- Department of Dermatology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaoqing Zhao
- Department of Dermatology, Rui Jin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
8
|
Annular epidermolytic ichthyosis: a case report and literature review. An Bras Dermatol 2020; 95:484-489. [PMID: 32482553 PMCID: PMC7335885 DOI: 10.1016/j.abd.2019.09.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 09/25/2019] [Indexed: 11/23/2022] Open
Abstract
Annular epidermolytic ichthyosis is a rare subtype of epidermolytic ichthyosis that is characterized by erythematous, polycyclic, and migratory scaly plaques accompanied by palmoplantar keratoderma. This report presents the case of an 8-year-old girl who developed migratory, erythematous, scaly plaques associated with palmoplantar keratoderma. The initial hypothesis was erythrokeratodermia variabilis et progressiva; however, the finding of epidermolytic hyperkeratosis in histopathological examination led to the diagnosis of annular epidermolytic ichthyosis.
Collapse
|
9
|
Juratli HA, Jägle S, Happle R, Avci P, Didona D, Fischer J. A Family with Palmar and Plantar Hyperkeratosis: A Quiz. Acta Derm Venereol 2020; 100:adv00064. [PMID: 32052849 PMCID: PMC9128890 DOI: 10.2340/00015555-3419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
is missing (Quiz).
Collapse
Affiliation(s)
- Hazem A Juratli
- Department of Dermatology and Allergology, Philipp University, DE-35043 Marburg, Germany.
| | | | | | | | | | | |
Collapse
|
10
|
Reolid A, Carrasco L, Noguera-Morel L, Torrelo A, Colmenero I, Ortiz-Cabrera NV, Hernández-Martin Á. Annular epidermolytic ichthyosis: An exceptional mild subtype of epidermolytic ichthyosis without genotype and phenotype correlation. JAAD Case Rep 2019; 6:46-50. [PMID: 31909138 PMCID: PMC6938839 DOI: 10.1016/j.jdcr.2019.10.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Alejandra Reolid
- Department of Dermatology, Hospital Infantil Niño Jesús, Madrid, Spain
| | - Loreto Carrasco
- Department of Dermatology, Fundación Jiménez Díaz, Madrid, Spain
| | | | - Antonio Torrelo
- Department of Dermatology, Hospital Infantil Niño Jesús, Madrid, Spain
| | - Isdabel Colmenero
- Department of Pathology, Hospital Infantil Niño Jesús, Madrid, Spain
| | | | - Ángela Hernández-Martin
- Department of Dermatology, Hospital Infantil Niño Jesús, Madrid, Spain
- Correspondence to: Ángela Hernández-Martin, MD, PhD, Department of Dermatology, Hospital Infantil Niño Jesús, Av De Menéndez Pelayo, 65, 28009, Madrid, Spain.
| |
Collapse
|
11
|
Zaki TD, Yoo KY, Kassardjian M, Choate KA. A p.478I>T KRT1 mutation in a case of annular epidermolytic ichthyosis. Pediatr Dermatol 2018; 35:e414-e415. [PMID: 30152556 PMCID: PMC7903949 DOI: 10.1111/pde.13643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Annular epidermolytic ichthyosis (AEI; Online Mendelian Inheritance in Man [OMIM]# 607602) is a rare subtype of epidermolytic ichthyosis that is characterized by polycyclic, migratory erythematous and scaly plaques. It typically results from dominant mutations in the keratin 1 or keratin 10 genes. We present the case of a 5-year-old girl who developed intermittent eruptions of pink, round, scaly, migratory plaques with palmoplantar keratoderma and was originally diagnosed with erythrokeratodermia variabilis et progressiva (EKVP). Genetic analysis revealed a c.1436T>C transition mutation in the keratin 1 gene, and histopathology showed epidermolysis and hyperkeratosis, confirming the diagnosis of AEI.
Collapse
Affiliation(s)
- Theodore D. Zaki
- Department of Dermatology, Yale University School of Medicine, New Haven, CT, USA
| | - Ki-Young Yoo
- Department of Dermatology, Kaiser Permanente South Bay, Harbor City, CA, USA
| | | | - Keith A. Choate
- Department of Dermatology, Yale University School of Medicine, New Haven, CT, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| |
Collapse
|
12
|
Guerra L, Castori M, Didona B, Castiglia D, Zambruno G. Hereditary palmoplantar keratodermas. Part II: syndromic palmoplantar keratodermas - Diagnostic algorithm and principles of therapy. J Eur Acad Dermatol Venereol 2018; 32:899-925. [DOI: 10.1111/jdv.14834] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 01/05/2018] [Indexed: 12/19/2022]
Affiliation(s)
- L. Guerra
- Laboratory of Molecular and Cell Biology; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - M. Castori
- Division of Medical Genetics; Casa Sollievo della Sofferenza-IRCCS; San Giovanni Rotondo Italy
| | - B. Didona
- Rare Skin Disease Center; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - D. Castiglia
- Laboratory of Molecular and Cell Biology; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - G. Zambruno
- Genetic and Rare Diseases Research Area and Dermatology Unit; Bambino Gesù Children's Hospital-IRCCS; Rome Italy
| |
Collapse
|
13
|
Sakiyama T, Kubo A. Hereditary palmoplantar keratoderma "clinical and genetic differential diagnosis". J Dermatol 2017; 43:264-74. [PMID: 26945534 DOI: 10.1111/1346-8138.13219] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 10/15/2015] [Indexed: 11/29/2022]
Abstract
Hereditary palmoplantar keratoderma (PPK) is a heterogeneous group of disorders characterized by hyperkeratosis of the palm and the sole skin. Hereditary PPK are divided into four groups--diffuse, focal, striate and punctate PPK--according to the clinical patterns of the hyperkeratotic lesions. Each group includes simple PPK, without associated features, and PPK with associated features, such as involvement of nails, teeth and other organs. PPK have been classified by a clinically based descriptive system. In recent years, many causative genes of PPK have been identified, which has confirmed and/or rearranged the traditional classifications. It is now important to diagnose PPK by a combination of the traditional morphological classification and genetic testing. In this review, we focus on PPK without associated features and introduce their morphological features, genetic backgrounds and new findings from the last decade.
Collapse
Affiliation(s)
- Tomo Sakiyama
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
| | - Akiharu Kubo
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
| |
Collapse
|
14
|
Banerjee S, Wu Q, Ying Y, Li Y, Shirota M, Neculai D, Li C. In silico predicted structural and functional insights of all missense mutations on 2B domain of K1/K10 causing genodermatoses. Oncotarget 2016; 7:52766-52780. [PMID: 27421141 PMCID: PMC5288147 DOI: 10.18632/oncotarget.10599] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 05/17/2016] [Indexed: 12/02/2022] Open
Abstract
The K1 and K10 associated genodermatoses are characterized by clinical symptoms of mild to severe redness, blistering and hypertrophy of the skin. In this paper, we set out to computationally investigate the structural and functional effects of missense mutations on the 2B domain of K1/K10 heterodimer and its consequences in disease phenotype. We modeled the structure of the K1/K10 heterodimer based on crystal structures for the human homolog K5/K14 heterodimer, and identified that the missense mutations exert their effects on stability and assembly competence of the heterodimer by altering physico-chemical properties, interatomic interactions, and inter-residue atomic contacts. Comparative structural analysis between all the missense mutations and SNPs showed that the location and physico-chemical properties of the substituted amino acid are significantly correlated with phenotypic variations. In particular, we find evidence that a particular SNP (K10, p.E443K) is a pathogenic nsSNP which disrupts formation of the hydrophobic core and destabilizes the heterodimer through the loss of interatomic interactions. Our study is the first comprehensive report analyzing the mutations located on 2B domain of K1/K10 heterodimeric coiled-coil complex.
Collapse
Affiliation(s)
- Santasree Banerjee
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
- BGI-Shenzhen, Shenzhen, China
| | - Qian Wu
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yuyi Ying
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yanni Li
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Matsuyuki Shirota
- Department of Applied Information Sciences, Graduate School of Information Sciences, Tohoku University, Sendai, Japan
| | - Dante Neculai
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Chen Li
- Department of Cell Biology and Medical Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|
15
|
Palombo R, Giannella E, Didona B, Annicchiarico-Petruzzelli M, Melino G, Terrinoni A. Cutaneous mosaicism, in KRT1 pI479T patient, caused by the somatic loss of the wild-type allele, leads to the increase in local severity of the disease. J Eur Acad Dermatol Venereol 2015; 30:847-51. [PMID: 25904304 DOI: 10.1111/jdv.13153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/19/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND Epidermolytic ichthyosis (BCIE, OMIM 113800), is an autosomal dominant disorder of the skin caused by mutations in keratin genes KRT1 and KRT10. We present two sporadic patients showing a mild diffuse ichthyosis with palmoplantar keratoderma. Interestingly, one of them shows a significant hyperkeratosis of palms and soles similar to those present in the Meleda disease (OMIM 248300). OBJECTIVE In this paper we would clarify the genetic difference between the two patients, giving rise to the different phenotype. METHODS Clinical evaluation, followed by histological and molecular analysis has been established for these patients. RESULTS We demonstrated the presence of a genetic cutaneous mosaicism. Both patients carry the KRT1 pI479T substitution, but in the palmoplantar areas of one of them, only the mutated allele is expressed (hemizygous). This leads to highlight a new type of cutaneous mosaic, the palmoplantar mosaicism.
Collapse
Affiliation(s)
- R Palombo
- IDI-IRCCS, Biochemistry Laboratory, c/o Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome, Italy
| | - E Giannella
- IDI-IRCCS, Biochemistry Laboratory, c/o Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome, Italy
| | - B Didona
- 1st Dermatological Division, IDI-IRCCS, Rome, Italy
| | - M Annicchiarico-Petruzzelli
- IDI-IRCCS, Biochemistry Laboratory, c/o Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome, Italy
| | - G Melino
- IDI-IRCCS, Biochemistry Laboratory, c/o Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome, Italy.,Toxicology Unit, Medical Research Council, Leicester University, Leicester, UK
| | - A Terrinoni
- IDI-IRCCS, Biochemistry Laboratory, c/o Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome, Italy
| |
Collapse
|
16
|
Sung JY, Oh SW, Kim SE, Kim SC. Mild phenotype of epidermolytic hyperkeratosis mimicking ichthyosis bullosa of Siemens is related to specific mutation in 2B domain of KRT1. J Dermatol Sci 2013; 70:220-2. [PMID: 23623204 DOI: 10.1016/j.jdermsci.2013.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 02/19/2013] [Accepted: 03/01/2013] [Indexed: 11/16/2022]
|
17
|
Abstract
The progress of molecular genetics helps clinicians to prove or exclude a suspected diagnosis for a vast and yet increasing number of genodermatoses. This leads to precise genetic counselling, prenatal diagnosis and preimplantation genetic haplotyping for many inherited skin conditions. It is also helpful in such occasions as phenocopy, late onset and incomplete penetrance, uniparental disomy, mitochondrial inheritance and pigmentary mosaicism. Molecular methods of two genodermatoses are explained in detail, i.e. genodermatoses with skin fragility and neurofibromatosis type 1.
Collapse
Affiliation(s)
- Vesarat Wessagowit
- Molecular Genetics Laboratory, The Institute of Dermatology, Bangkok, Thailand.
| |
Collapse
|
18
|
Ang-Tiu CU, Nicolas MEO. Ichthyosis bullosa of Siemens. J Dermatol Case Rep 2012; 6:78-81. [PMID: 23091584 DOI: 10.3315/jdcr.2012.1107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 02/27/2012] [Indexed: 12/16/2022]
Abstract
BACKGROUND Ichthyosis bullosa of Siemens (IBS) is a rare hyperkeratotic blistering condition caused by mutations in keratin 2e gene. MAIN OBSERVATIONS This is a case of a 18-year-old female with generalized blisters, erosions and thickened skin since she was 3 months old. As she aged, there was decrease in development of blisters and erosions, with accompanying increase in severity of hyperkeratosis. Skin punch biopsy showed overlying basket weave hyperkeratosis and acanthosis, prominent vacuolization of the granular cell layer, and intraepidermal blisters with the split at the granular layer. The patient was treated with emollients, with marked improvement. CONCLUSIONS Mutations in the different keratin genes have been shown to underlie a wide range of disorders of keratinization. Epidermolytic hyperkeratosis and ichthyosis bullosa of Siemens are distinct disorders with mutations in different genes. Although molecular genetic testing should ideally be done for confirmation of diagnosis, ichthyosis bullosa of Siemens could be diagnosed in this patients based on key clinical characteristics.
Collapse
Affiliation(s)
- Charlene U Ang-Tiu
- Section of Dermatology, Department of Medicine, UP-Philippine General Hospital, Manila, Philippines
| | | |
Collapse
|
19
|
Zeng YP, Chai WX, Fang K, Sun QN, Zuo YG. A recurrent missense mutation of keratin 1 gene in a Chinese family with epidermolytic hyperkeratosis (severe palmoplantar hyperkeratosis, type 1). Int J Dermatol 2012; 51:182-5. [PMID: 22250628 DOI: 10.1111/j.1365-4632.2011.05202.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Epidermolytic hyperkeratosis (EHK) is an autosomal dominantly inherited genodermatosis manifesting with blistering and erythroderma in infancy and widespread hyperkeratosis of the skin, particularly over flexural areas, in adulthood. It can be classified into six clinical phenotypes. CASE REPORT We report the case of a 25-year-old man who presented with severe palmoplantar thickening and hyperkeratosis over the flexures for nearly 24 years. Histopathological findings showed characteristic features of EHK, and EHK type PS-1 (severe palmoplantar hyperkeratosis, type 1) was suspected. Further investigation revealed that his father, sister, and nephew (the son of his sister) were similarly affected. A heterozygous missense mutation in exon 7 of KRT1 (c.1436T>C), resulting in an isoleucine to threonine substitution at codon 479 (designated p.I479T), was detected in all affected individuals within the pedigree. DISCUSSION Up to now, there has been one sporadic case and one family (including 14 affected individuals) with EHK type PS-1 reported since DiGiovanna and Bale described 25 patients (from two families) with EHK type PS-1 out of 51 patients (from 21 families) with EHK. Although the mutation (c.1436T>C) in KRT1 reported here is a recurrent one, it has not been reported in Chinese patients with EHK. It is interesting to note that the same mutation in KRT1 can cause different phenotypes of EHK. CONCLUSIONS We expand the clinical heterogeneity of EHK due to the same mutation (c.1436T>C) in KRT1 and enrich the database of the KRT1 gene mutations underlying EHK in the Chinese population.
Collapse
Affiliation(s)
- Yue-Ping Zeng
- Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | | | | | | | | |
Collapse
|
20
|
Arin MJ, Oji V, Emmert S, Hausser I, Traupe H, Krieg T, Grimberg G. Expanding the keratin mutation database: novel and recurrent mutations and genotype-phenotype correlations in 28 patients with epidermolytic ichthyosis. Br J Dermatol 2011; 164:442-7. [PMID: 21271994 DOI: 10.1111/j.1365-2133.2010.10096.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Epidermolytic ichthyosis (EI) is a hereditary keratinization disorder caused by mutations in the keratin 1 (KRT1) or keratin 10 (KRT10) genes. In most cases of severe EI, heterozygous single point mutations are found at the highly conserved helix boundary motifs of KRT1 and KRT10 that play a critical role in filament formation. The presence of palmoplantar keratoderma suggests KRT1 mutations, whereas KRT10 mutations in most instances give rise to the nonpalmoplantar variants. OBJECTIVES To identify the underlying mutations in patients with EI and to correlate genotype and phenotype. METHODS Mutation analysis was performed in 28 patients with EI by direct sequencing of KRT1 and KRT10 genes. RESULTS We identified 14 different mutations, of which four have not been published previously. CONCLUSIONS Identification of novel mutations and genotype-phenotype correlations in EI allows improved understanding of disease pathogenesis as well as better patient management.
Collapse
Affiliation(s)
- M J Arin
- Department of Dermatology, University of Cologne, Kerpener Strasse 62, 50931 Cologne, Germany.
| | | | | | | | | | | | | |
Collapse
|
21
|
Keratin gene mutations in disorders of human skin and its appendages. Arch Biochem Biophys 2010; 508:123-37. [PMID: 21176769 DOI: 10.1016/j.abb.2010.12.019] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 12/16/2010] [Indexed: 11/21/2022]
Abstract
Keratins, the major structural protein of all epithelia are a diverse group of cytoskeletal scaffolding proteins that form intermediate filament networks, providing structural support to keratinocytes that maintain the integrity of the skin. Expression of keratin genes is usually regulated by differentiation of the epidermal cells within the stratifying squamous epithelium. Amongst the 54 known functional keratin genes in humans, about 22 different genes including, the cornea, hair and hair follicle-specific keratins have been implicated in a wide range of hereditary diseases. The exact phenotype of each disease usually reflects the spatial expression level and the types of mutated keratin genes, the location of the mutations and their consequences at sub-cellular levels as well as other epigenetic and/or environmental factors. The identification of specific pathogenic mutations in keratin disorders formed the basis of our understanding that led to re-classification, improved diagnosis with prognostic implications, prenatal testing and genetic counseling in severe keratin genodermatoses. Molecular defects in cutaneous keratin genes encoding for keratin intermediate filaments (KIFs) causes keratinocytes and tissue-specific fragility, accounting for a large number of genetic disorders in human skin and its appendages. These diseases are characterized by keratinocytes fragility (cytolysis), intra-epidermal blistering, hyperkeratosis, and keratin filament aggregation in severely affected tissues. Examples include epidermolysis bullosa simplex (EBS; K5, K14), keratinopathic ichthyosis (KPI; K1, K2, K10) i.e. epidermolytic ichthyosis (EI; K1, K10) and ichthyosis bullosa of Siemens (IBS; K2), pachyonychia congenita (PC; K6a, K6b, K16, K17), epidermolytic palmo-plantar keratoderma (EPPK; K9, (K1)), monilethrix (K81, K83, K86), ectodermal dysplasia (ED; K85) and steatocystoma multiplex. These keratins also have been identified to have roles in apoptosis, cell proliferation, wound healing, tissue polarity and remodeling. This review summarizes and discusses the clinical, ultrastructural, molecular genetics and biochemical characteristics of a broad spectrum of keratin-related genodermatoses, with special clinical emphasis on EBS, EI and PC. We also highlight current and emerging model tools for prognostic future therapies. Hopefully, disease modeling and in-depth understanding of the molecular pathogenesis of the diseases may lead to the development of novel therapies for several hereditary cutaneous diseases.
Collapse
|
22
|
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.
Collapse
|
23
|
The molecular basis of human keratin disorders. Hum Genet 2009; 125:355-73. [DOI: 10.1007/s00439-009-0646-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2009] [Accepted: 02/18/2009] [Indexed: 01/01/2023]
|
24
|
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.
| | | | | | | |
Collapse
|
25
|
Sheth N, Greenblatt D, McGrath JA. New KRT10 gene mutation underlying the annular variant of bullous congenital ichthyosiform erythroderma with clinical worsening during pregnancy. Br J Dermatol 2007; 157:602-4. [PMID: 17596149 DOI: 10.1111/j.1365-2133.2007.08054.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- N Sheth
- Department of Dermatology, Ealing Hospital, Southall UB1 3HW, UK.
| | | | | |
Collapse
|
26
|
Uitto J, Richard G, McGrath JA. Diseases of epidermal keratins and their linker proteins. Exp Cell Res 2007; 313:1995-2009. [PMID: 17531221 PMCID: PMC2578874 DOI: 10.1016/j.yexcr.2007.03.029] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 03/07/2007] [Accepted: 03/12/2007] [Indexed: 12/01/2022]
Abstract
Epidermal keratins, a diverse group of structural proteins, form intermediate filament networks responsible for the structural integrity of keratinocytes. The networks extend from the nucleus of the epidermal cells to the plasma membrane where the keratins attach to linker proteins which are part of desmosomal and hemidesmosomal attachment complexes. The expression of specific keratin genes is regulated by differentiation of the epidermal cells within the stratifying squamous epithelium. Progress in molecular characterization of the epidermal keratins and their linker proteins has formed the basis to identify mutations which are associated with distinct cutaneous manifestations in patients with genodermatoses. The precise phenotype of each disease apparently reflects the spatial level of expression of the mutated genes, as well as the types and positions of the mutations and their consequences at mRNA and protein levels. Identification of specific mutations in keratinization disorders has provided the basis for improved diagnosis and subclassification with prognostic implications and has formed the platform for prenatal testing and preimplantation genetic diagnosis. Finally, precise knowledge of the mutations is a prerequisite for development of gene therapy approaches to counteract, and potentially cure, these often devastating and currently intractable diseases.
Collapse
Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | | | | |
Collapse
|
27
|
Uezato H, Yamamoto YI, Kuwae C, Nonaka K, Oshiro M, Kariya KI, Nonaka S. A case of bullous congenital ichthyosiform erythroderma (BCIE) caused by a mutation in the 1A helix initiation motif of keratin 1. J Dermatol 2006; 32:801-8. [PMID: 16361731 DOI: 10.1111/j.1346-8138.2005.tb00848.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2004] [Accepted: 04/27/2005] [Indexed: 01/14/2023]
Abstract
Bullous congenital ichthyosiform erythroderma (BCIE) is an autosomally dominant inherited disorder characterized by erythematous, erosive, and bullous skin lesions over the entire body at birth and abnormal hyperkeratosis on the palmoplantar sufaces as the patient grows older. BCIE is caused by a mutation in the keratin 1 (K1) and/or keratin 10 (K10) genes, and most pathogenic mutations are found within the helix initiation and termination motifs of the central helical rod domain (K1 and K10) or the upstream H1 homology domain (K10). In addition to inherited cases, sporadic cases due to a new mutation account for approximately half the total cases of BCIE. We report herein a typical sporadic case of BCIE with erythroderma, erosion, and blisters on the entire body surface at birth and palmoplantar and flexuaral areas of hyperkeratosis in the later stage. We found in this case a novel mutation, 559C to T, at amino acid position 187, which resulted in a leucine to phenylalanine substitution within the helix initiation motif of K1.
Collapse
Affiliation(s)
- Hiroshi Uezato
- Department of Dermatology, School of Medicine, University of the Ryukyus, Okinawa, Japan
| | | | | | | | | | | | | |
Collapse
|
28
|
McLean WHI, Smith FJD, Cassidy AJ. Insights into genotype-phenotype correlation in pachyonychia congenita from the human intermediate filament mutation database. J Investig Dermatol Symp Proc 2005; 10:31-6. [PMID: 16250207 DOI: 10.1111/j.1087-0024.2005.10205.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Keratins are the intermediate filament proteins specifically expressed by epithelial cells. The Human Genome Project has uncovered a total of 54 functional keratin genes that are differentially expressed in specific epithelial structures of the body, many of which involve the epidermis and its appendages. Pachyonychia congenita (PC) is a group of autosomal dominant genodermatoses affecting the nails, thick skin and other ectodermal structures, according to specific sub-type. The major clinical variants of the disorder (PC-1 and PC-2) are known to be caused by dominant-negative mutations in one of four differentiation-specific keratins: K6a, K6b, K16, and K17. A total of 20 human keratin genes are currently linked to single-gene disorders or are predisposing factors in complex traits. In addition, a further six intermediate filament genes have been linked to other non-epithelial genetic disorders. We have established a comprehensive mutation database that catalogs all published independent occurrences of intermediate filament mutations (http://www.interfil.org), with details of phenotypes, published papers, patient support groups and other information. Here, we review the genotype-phenotype trends emerging from the spectrum of mutations in these genes and apply these correlations to make predictions about PC phenotypes based on the site of mutation and keratin pair involved.
Collapse
Affiliation(s)
- W H Irwin McLean
- Epithelial Genetics Group, Human Genetics Unit, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, UK.
| | | | | |
Collapse
|
29
|
Abstract
In the years following the initial reports of keratin gene mutations in epidermolysis bullosa simplex, great strides have been made in understanding the basic biology of human keratins and in understanding the etiology and pathogenesis of a number of specific human single gene disorders. A total of 19 human keratin genes is now linked to specific diseases. This article summarizes current knowledge in relation to basic keratin biology, known disease associations, and genotype correlation in this diverse and complex group of conditions.
Collapse
Affiliation(s)
- Alan D Irvine
- Department of Paediatric Dermatology, Our Lady's Hospital for Sick Children, Crumlin Dublin 12, Ireland.
| |
Collapse
|
30
|
|
31
|
|
32
|
Abstract
The association of keratin mutations with genetic skin fragility disorders is now one of the best-established examples of cytoskeleton disorders. It has served as a paradigm for many other diseases and has been highly informative for the study of intermediate filaments and their associated components, in helping to understand the functions of this large family of structural proteins. The keratin diseases have shown unequivocally that, at least in the case of the epidermal keratins, a major function of intermediate filaments is to provide physical resilience for epithelial cells. This review article reflects on the variety of phenotypes arising from mutations in keratins and the reasons for this variation.
Collapse
Affiliation(s)
- E B Lane
- Cancer Research UK Cell Structure Research Group, Division of Cell and Developmental Biology, University of Dundee School of Life Sciences, MSI/WTB Complex, Dow Street, Dundee DD1 5EH, UK.
| | | |
Collapse
|
33
|
Terron-Kwiatkowski A, Terrinoni A, Didona B, Melino G, Atherton DJ, Irvine AD, McLean WHI. Atypical epidermolytic palmoplantar keratoderma presentation associated with a mutation in the keratin 1 gene. Br J Dermatol 2004; 150:1096-103. [PMID: 15214894 DOI: 10.1111/j.1365-2133.2004.05967.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant genodermatosis characterized by epidermolytic hyperkeratosis strictly confined to the palms and soles, and usually associated with mutations in the keratin K9 gene (KRT9). Mutations in the keratin K1 gene (KRT1) have been shown to underlie a variety of phenotypes typically involving generalized epidermolytic hyperkeratosis, but in some cases the phenotype can be more regionally restricted. OBJECTIVES To identify the genetic defect in two unrelated families initially presenting with EPPK but where careful examination revealed hyperkeratosis extending on to the proximal wrist flexure. Methods Linkage analysis and DNA sequencing. RESULTS We found that this phenotype is caused by a heterozygous missense mutation in the K1 gene, designated I479T. This mutation lies in the highly conserved helix termination motif of K1, previously shown to be important for keratin assembly and filament formation. In general, mutations in this region of keratins are associated with more severe disease phenotypes. However, K1 mutations in this region and the I479T mutation in particular have previously been associated with both severe and mild bullous congenital ichthyosiform erythroderma phenotypes. When further clinical enquiries were made, several affected individuals in the families studied here were found to have had transient flexural peeling and hyperkeratosis in the neonatal period. CONCLUSIONS K1 mutations may underlie a phenotype closely resembling EPPK. A history of transient flexural peeling and hyperkeratosis in childhood and palmoplantar keratoderma which extends beyond the boundary of the palmoplantar margins may indicate a K1 mutation rather than a K9 defect. As K1 mutations are also associated with severe widespread phenotypes, with important implications for prognostic and genetic counselling, whole body examination is recommended for patients presenting with EPPK.
Collapse
|
34
|
Barnhart KF, Credille KM, Ambrus A, Dunstan RW. A Heritable Keratinization Defect of the Superficial Epidermis in Norfolk Terriers. J Comp Pathol 2004; 130:246-54. [PMID: 15053927 DOI: 10.1016/j.jcpa.2003.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2003] [Accepted: 11/06/2003] [Indexed: 11/25/2022]
Abstract
Although well-characterized in man, abnormal cornification secondary to heritable superficial keratin defects is rarely reported in animals. This report describes a mild cornification defect in seven related Norfolk terrier dogs. Lesions were present at birth and pedigree analysis suggested an autosomal recessive mode of inheritance. The affected dogs had hyperpigmented skin with scaling following mild trauma. The lesions were generalized but most prominent in the glabrous skin of the axillary and inguinal regions-areas where the epidermis is not protected by hair and is subject to frequent trauma. The most striking histological change was vacuolation in the upper epidermis, which often resulted in epidermolysis and blister formation. All of the affected dogs showed similar gross and histological changes. Ultrastructural changes included abnormal keratin filament clumping, prominent clear spaces in the cytoplasm of suprabasal keratinocytes, and abnormal keratohyaline granules. Immunohistochemical labelling for keratin 10 demonstrated a lack of expression in the superficial epidermis of affected dogs. All of the morphological changes noted in the Norfolk terriers were consistent with a mild form of a heritable defect in superficial keratin synthesis.
Collapse
Affiliation(s)
- K F Barnhart
- Department of Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843-4467, USA
| | | | | | | |
Collapse
|
35
|
|
36
|
Abstract
Keratins are the type I and II intermediate filament proteins which form a cytoskeletal network within all epithelial cells. They are expressed in pairs in a tissue- and differentiation-specific fashion. Epidermolysis bullosa simplex (EBS) was the first human disorder to be associated with keratin mutations. The abnormal keratin filament aggregates observed in basal cell keratinocytes of some EBS patients are composed of keratins K5 and K14. Dominant mutations in the genes encoding these proteins were shown to disrupt the keratin filament cytoskeleton resulting in cells that are less resilient and blister with mild physical trauma. Identification of mutations in other keratin genes soon followed with attention focussed on disorders showing abnormal clumping of keratin filaments in specific cells. For example, in bullous congenital ichthyosiform erythroderma, clumping of filaments in the suprabasal cells led to the identification of mutations in the suprabasal keratins, K1 and K10. Mutations have now been identified in 18 keratins, all of which produce a fragile cell phenotype. These include ichthyosis bullosa of Siemens (K2e), epidermolytic palmoplantar keratoderma (K1, K9), pachyonychia congenita (K6a, K6b, K16, K17), white sponge nevus (K4, K13), Meesmann's corneal dystrophy (K3, K12), cryptogenic cirrhosis (K8, K18) and monilethrix (hHb6, hHb1).In general, these disorders are inherited as autosomal dominant traits and the mutations act in a dominant-negative manner. Therefore, treatment in the form of gene therapy is difficult, as the mutant gene needs to be inactivated. Ways of achieving this are actively being studied. Reliable mutation detection methods from genomic DNA are now available. This enables rapid screening of patients for keratin mutations. For some of the more severe phenotypes, prenatal diagnosis may be requested and this can now be performed from chorionic villus samples at an early stage of the pregnancy. This review article describes the discovery of, to date, mutations in 18 keratin genes associated with inherited human diseases.
Collapse
Affiliation(s)
- Frances Smith
- Epithelial Genetics Group, Human Genetics Unit, University of Dundee, Ninewells Hospital and Medical School, Dundee, UK.
| |
Collapse
|
37
|
Terron-Kwiatkowski A, Paller AS, Compton J, Atherton DJ, McLean WHI, Irvine AD. Two cases of primarily palmoplantar keratoderma associated with novel mutations in keratin 1. J Invest Dermatol 2002; 119:966-71. [PMID: 12406346 DOI: 10.1046/j.1523-1747.2002.00186.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutations in keratin 1 were initially described in the classical form of bullous congenital ichthyosiform erythroderma (also known as epidermolytic hyperkeratosis). More recently the range of phenotypes associated with mutations in this gene has been extended to include annular ichthyosiform erythroderma and mild epidermolytic palmoplantar keratoderma. Here we present two novel mutations in the keratin 1 gene (KRT1): a 5' donor splice site mutation in exon 1 (591 + 2T > A) that predicts a 22 amino acid in-frame deletion in the keratin 1 1A domain; and an in-frame deletion in exon 7 (1376del24) that predicts a foreshortened 2B coiled-coil domain of keratin 1. In each case these mutations are associated with palmoplantar keratoderma and mild ichthyosis, largely limited to the flexural areas. These mutations appear to have a less damaging effect than previously reported mis-sense mutations sited in the helix boundary motifs. This report extends the range of phenotypes associated with mutations in KRT1.
Collapse
Affiliation(s)
- Ana Terron-Kwiatkowski
- Human Genetics Unit, University of Dundee, Ninewells Hospital & Medical School, Dundee, U.K
| | | | | | | | | | | |
Collapse
|
38
|
Whittock NV, Ashton GH, Griffiths WA, Eady RA, McGrath JA. New mutations in keratin 1 that cause bullous congenital ichthyosiform erythroderma and keratin 2e that cause ichthyosis bullosa of Siemens. Br J Dermatol 2001; 145:330-5. [PMID: 11531804 DOI: 10.1046/j.1365-2133.2001.04327.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The intermediate filaments of epithelial cells are formed by keratins, a family of structurally related proteins, which are expressed in pairs of acidic (type I) and basic (type II) polypeptides in a tissue- and differentiation-specific manner. Mutations in the genes encoding several keratins have been implicated in the pathogenesis of diseases of keratinization. We report molecular analysis of two patients with the rare autosomal dominant disorders bullous congenital ichthyosiform erythroderma (BCIE) and ichthyosis bullosa of Siemens (IBS). Previous studies have shown that these genodermatoses are due to mutations in the KRT1 and KRT2E genes, respectively. We report a new amino acid substitution mutation in codon 155 of KRT1 (valine to aspartic acid) in the conserved H1 domain of the protein in the patient with BCIE. We also report a novel amino acid substitution mutation in codon 192 of KRT2E (asparagine to lysine) in the conserved 1A helix initiation peptide of the protein in the patient with IBS. Our results demonstrate that these mutations are deleterious to keratin filament network stability and lead to specific clinical inherited disorders of keratinization.
Collapse
Affiliation(s)
- N V Whittock
- Department of Cell and Molecular Pathology, St John's Institute of Dermatology, The Guy's, King's College, London, UK.
| | | | | | | | | |
Collapse
|
39
|
Hatsell SJ, Eady RA, Wennerstrand L, Dopping-Hepenstal P, Leigh IM, Munro C, Kelsell DP. Novel splice site mutation in keratin 1 underlies mild epidermolytic palmoplantar keratoderma in three kindreds. J Invest Dermatol 2001; 116:606-9. [PMID: 11286630 DOI: 10.1046/j.1523-1747.2001.13041234.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report a novel mutation in the exon 6 splice donor site of keratin 1 (G4134A) that segregates with a palmoplantar keratoderma in three kindreds. The nucleotide substitution leads to the utilization of a novel in-frame splice site 54 bases downstream of the mutation with the subsequent insertion of 18 amino acids into the 2B rod domain. This mutation appears to have a milder effect than previously described mutations in the helix initiation and termination sequence on the function of the rod domain, with regard to filament assembly and stability. Affected individuals displayed only mild focal epidermolysis in the spinous layer of palmoplantar epidermis, in comparison with cases of bullous congenital ichthyosiform erythroderma also due to keratin 1 mutations, which show widespread and severe epidermolysis. This study describes a novel mutation in KRT1 that results in a phenotype distinct from classical bullous congenital ichthyosiform erythroderma.
Collapse
Affiliation(s)
- S J Hatsell
- Center for Cutaneous Research, St. Bartholomews, and the Royal London School of Medicine and Dentistry, Queen Mary College, London, UK
| | | | | | | | | | | | | |
Collapse
|
40
|
McGrath JA, Eady RA. Recent advances in the molecular basis of inherited skin diseases. ADVANCES IN GENETICS 2001; 43:1-32. [PMID: 11037297 DOI: 10.1016/s0065-2660(01)43002-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Over the last few years the molecular basis of several inherited skin diseases has been delineated. Some discoveries have stemmed from a candidate gene approach using clinical, biochemical, immunohistochemical, and ultrastructural clues, while others have arisen from genetic linkage and positional cloning analyses. Notable advances have included elucidation of specific gene pathology in the major forms of inherited skin fragility, ichthyosis, and keratoderma. These findings have led to a better understanding of the significance of individual structural proteins and regulatory enzymes in keratinocyte adhesion and differentiation. From a clinical perspective, the advances have led to better genetic counseling in many disorders, the development of DNA-based prenatal diagnosis, and a foundation for planning newer forms of treatment, including somatic gene therapy, in selected conditions.
Collapse
Affiliation(s)
- J A McGrath
- Department of Cell and Molecular Pathology, St John's Institute of Dermatology, The Guy's, Kings College and St Thomas' Hospital Medical School, St Thomas' Hospital, London, United Kingdom.
| | | |
Collapse
|
41
|
Xia JH, Yang YF, Deng H, Tang BS, Tang DS, He YG, Xia K, Chen SX, Li YX, Pan Q, Long ZG, Dai HP, Liao XD, Xiao JF, Liu ZR, Lu CY, Yu KP, Deng HX. Identification of a locus for disseminated superficial actinic porokeratosis at chromosome 12q23.2-24.1. J Invest Dermatol 2000; 114:1071-4. [PMID: 10844547 DOI: 10.1046/j.1523-1747.2000.00978.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Disseminated superficial actinic porokeratosis is an autosomal dominant cutaneous disorder characterized by many uniformly small, minimal, annular, anhidrotic, and keratotic lesions. The genetic basis for this disease is unknown. Using a genomewide search in a large Chinese family, we identified a locus at chromosome 12q23.2-24. 1 responsible for disseminated superficial actinic porokeratosis. The fine mapping study indicates that the disseminated superficial actinic porokeratosis gene is located within a 9.6 cM region between markers D12S1727 and D12S1605, with a maximum two-point LOD score of 20.53 (theta = 0.00) at D12S78. This is the first locus identified for a genetic disease where the major phenotype is porokeratosis. The study provides a map location for isolation of a gene causing disseminated superficial actinic porokeratosis.
Collapse
Affiliation(s)
- J H Xia
- National Laboratory of Medical Genetics of China, Department of Neurology, Xiangya Hospital, Hunan Medical University, Changsha, China.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Yoneda K, Morita E, Akiyama M, Kusunoki T, Yamada S, Yamamoto S. Annular epidermolytic ichthyosis. Br J Dermatol 1999; 141:748-50. [PMID: 10583132 DOI: 10.1046/j.1365-2133.1999.03125.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
43
|
Abstract
Phototherapies like photodynamic therapy (PDT), UVA1, UVB, and PUVA treat skin diseases. These phototherapies work because they alter cytokine profiles, change immune cytotoxicity in the skin, and directly kill diseased cells by apoptosis. Apoptosis is a term that only describes the morphologic changes a cell undergoes during this mode of cell death. The terms "immediate", "intermediate", and "delayed" apoptosis segregate the different apoptotic mechanisms into three kinetic categories, whereas the terms preprogrammed cell death (pre-PCD) and programmed cell death (PCD) describe the underlying mechanisms. Immediate apoptosis (T< or =0.5 h post-exposure) is triggered by singlet-oxygen damage that opens the mitochondrial megachannel, which can be mediated by PDT or UVA1 radiation. It is a pre-PCD mechanism of apoptosis, i.e., protein synthesis is not required post-insult, because all the necessary components are constitutively synthesized and only need to be activated. Intermediate apoptosis (T< or =4 h>0.5 h) is initiated by receptor cross-linking on the plasma membrane, which can be achieved using high doses of UVB or UVC radiation. It is also a pre-PCD mechanism. Delayed apoptosis (T>4 h) is induced by DNA damage that can be caused by X-rays, PUVA, UVC, UVB, UVA, and PDT. It is a PCD mechanism of apoptosis, i.e., protein synthesis is required post-insult. These three apoptotic mechanisms each access one of two "points-of-no-return" located on the mitochondrial membrane, which activate different, but not mutually exclusive, final pathways of apoptosis. This review discusses the latest findings on these apoptotic mechanisms and their implications in phototherapies.
Collapse
Affiliation(s)
- D E Godar
- Center for Devices and Radiological Health, Food and Drug Administration, Rockville, Maryland 20857, USA.
| |
Collapse
|