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Beeler JS, Bolton KL. How low can you go?: Methodologic considerations in clonal hematopoiesis variant calling. Leuk Res 2023; 135:107419. [PMID: 37956474 DOI: 10.1016/j.leukres.2023.107419] [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: 06/26/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023]
Abstract
Clonal hematopoiesis (CH) is defined by the presence of an expanded clonal hematopoietic cell population due to an acquired mutation conferring a selective growth advantage and is known to predispose to hematologic malignancy. In this review, we discuss sequencing methods for CH detection in bulk sequencing data and corresponding bioinformatic approaches for variant calling, filtering, and curation. We detail practical recommendations for CH calling. Finally, we discuss how improvements in CH sequencing and bioinformatic approaches will enable the characterization of CH trajectories, its impact on human health, and therapeutic approaches to mitigate its adverse effects.
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Affiliation(s)
- J Scott Beeler
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Kelly L Bolton
- Division of Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
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2
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Kubanov AA, Chikin VV, Karamova AE, Monchakovskaya ES. Junctional epidermolysis bullosa: genotype-phenotype correlations. VESTNIK DERMATOLOGII I VENEROLOGII 2022. [DOI: 10.25208/vdv1391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Junctional epidermolysis bullosa most commonly results from mutations in theLAMA3, LAMB3, LAMC2, COL17A1, ITGA6 and ITGB4genes. Junctional epidermolysis bullosa is characterized by clinical heterogeneity. To date, scientific findings allow to evaluate correlations between the severity of clinical manifestations and genetic defects underlying in the development of the disease. A systematic literature search was performed using PubMed and RSCI, and keywords including junctional epidermolysis bullosa, laminin 332, collagen XVII, 64 integrin. The review includes description of clinical findings of junctional epidermolysis bullosa, mutation location and types, its impact on protein production and functions. To evaluate the impact of gene mutation on protein functions, this review explores the structure and functions of lamina lucida components, including laminin 332, collagen XVII and 64 integrin, which are frequently associated with the development of junctional epidermolysis bullosa. The correlation between severe types of junctional epidermolysis bullosa and mutations resulting in premature stop codon generation and complete absence of protein expression has been described. Although, genotype-phenotype correlations should be analyzed carefully due to mechanisms which enable to improve protein expression.
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3
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Revertant Mosaicism in Genodermatoses: Natural Gene Therapy Right before Your Eyes. Biomedicines 2022; 10:biomedicines10092118. [PMID: 36140224 PMCID: PMC9495737 DOI: 10.3390/biomedicines10092118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/23/2022] [Accepted: 08/23/2022] [Indexed: 11/19/2022] Open
Abstract
Revertant mosaicism (RM) is the intriguing phenomenon in which nature itself has successfully done what medical science is so eagerly trying to achieve: correcting the effect of disease-causing germline variants and thereby reversing the disease phenotype back to normal. RM was molecularly confirmed for the first time in a genodermatosis in 1997, the genetic skin condition junctional epidermolysis bullosa (EB). At that time, RM was considered an extraordinary phenomenon. However, several important discoveries have changed this conception in the past few decades. First, RM has now been identified in all major subtypes of EB. Second, RM has also been identified in many other genodermatoses. Third, a theoretical mathematical exercise concluded that reverse mutations should be expected in all patients with a recessive subtype of EB or any other genodermatosis. This has shifted the paradigm from RM being an extraordinary phenomenon to it being something that every physician working in the field of genodermatoses should be looking for in every patient. It has also raised hope for new treatment options in patients with genodermatoses. In this review, we summarize the current knowledge on RM and discuss the perspectives of RM for the future treatment of patients with genodermatoses.
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4
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Aquaron R, Lasseaux E, Kelekele J, Bonello-Palot N, Badens C, Arveiler B, Tshilolo L. Co-occurrence of oculocutaneous albinism type 2 and mild sickle cell disease explained by HbS/βthal genotype in an individual from the Democratic Republic of Congo. Eur J Med Genet 2022; 65:104594. [PMID: 35964929 DOI: 10.1016/j.ejmg.2022.104594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/26/2022] [Accepted: 08/07/2022] [Indexed: 11/03/2022]
Abstract
Oculocutaneous albinism type 2 (OCA2) is a pigmentation disorder characterized by hypopigmentation of the skin, hair and eyes and ocular features. Sickle cell disease (SCD) is caused either by homozygosity of the beta globin gene variant c.20A > T/p.Glu6Val giving rise to severe anemia or by combined abnormal hemoglobins (HbS/βthal) leading to mild SCD. We report a 45 years old female patient from the Democratic Republic of Congo affected with these two disorders. She presented with creamy white skin and numerous pigmented patches called dendritic freckles, nystagmus, foveal hypoplasia grade 2, photophobia and very poor visual acuity. Sequencing of the OCA2 gene identified the common exon 7 deletion and a new pathogenic variant c.1444A > C/p.Thr482Pro. She had mild SCD with a total Hb level of 101 g/l. Hbβ sequencing identified variants c.20A > T giving rise to HbS and c.315 + 1 G > A characteristic of β-thalassemia. A heterozygous 3.7 kb deletion of the α globin gene was also found. The combined Hbβ/α globin genotype explains the mild SCD phenotype. Co-occurrence of OCA2 and SCD raises the question whether the patient's phenotype simply results from the addition of the two diseases' phenotypes or whether interaction between the two diseases modulates the phenotype of each other.
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Affiliation(s)
- Robert Aquaron
- Faculté de Médecine, Aix-Marseille Université, 27 Boulevard Jean Moulin, 13385, Marseille, cedex 5, France
| | - Eulalie Lasseaux
- Service de Génétique Médicale, CHU de Bordeaux, Hôpital Pellegrin, 1 place Amelie Raba Léon, 33076, Bordeaux Cedex, France
| | - Joseph Kelekele
- Cliniques Universitaires de Kinshasa, Département d'Ophtalmologie. UNIKIN. Mont Amba, Kinshasa, Democratic Republic of the Congo, The
| | | | - Catherine Badens
- Laboratoire de Génétique Moléculaire, Hôpital d'enfants de la Timone, Marseille, France
| | - Benoit Arveiler
- Service de Génétique Médicale, CHU de Bordeaux, Hôpital Pellegrin, 1 place Amelie Raba Léon, 33076, Bordeaux Cedex, France; Laboratoire Maladies Rares, Génétique et Métabolisme, INSERM U 1211, Université de Bordeaux, France.
| | - Leon Tshilolo
- Centre Hospitalier Monkole, CEFA/ Institut de Recherche Biomédicale, Mont-Ngafula, BP 817, Kinshasa, Democratic Republic of the Congo, The
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5
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Morren MA, Legius E, Giuliano F, Hadj-Rabia S, Hohl D, Bodemer C. Challenges in Treating Genodermatoses: New Therapies at the Horizon. Front Pharmacol 2022; 12:746664. [PMID: 35069188 PMCID: PMC8766835 DOI: 10.3389/fphar.2021.746664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Accepted: 11/29/2021] [Indexed: 01/28/2023] Open
Abstract
Genodermatoses are rare inherited skin diseases that frequently affect other organs. They often have marked effects on wellbeing and may cause early death. Progress in molecular genetics and translational research has unravelled many underlying pathological mechanisms, and in several disorders with high unmet need, has opened the way for the introduction of innovative treatments. One approach is to intervene where cell-signaling pathways are dysregulated, in the case of overactive pathways by the use of selective inhibitors, or when the activity of an essential factor is decreased by augmenting a molecular component to correct disequilibrium in the pathway. Where inflammatory reactions have been induced by a genetically altered protein, another possible approach is to suppress the inflammation directly. Depending on the nature of the genodermatosis, the implicated protein or even on the particular mutation, to correct the consequences or the genetic defect, may require a highly personalised stratagem. Repurposed drugs, can be used to bring about a "read through" strategy especially where the genetic defect induces premature termination codons. Sometimes the defective protein can be replaced by a normal functioning one. Cell therapies with allogeneic normal keratinocytes or fibroblasts may restore the integrity of diseased skin and allogeneic bone marrow or mesenchymal cells may additionally rescue other affected organs. Genetic engineering is expanding rapidly. The insertion of a normal functioning gene into cells of the recipient is since long explored. More recently, genome editing, allows reframing, insertion or deletion of exons or disruption of aberrantly functioning genes. There are now several examples where these stratagems are being explored in the (pre)clinical phase of therapeutic trial programmes. Another stratagem, designed to reduce the severity of a given disease involves the use of RNAi to attenuate expression of a harmful protein by decreasing abundance of the cognate transcript. Most of these strategies are short-lasting and will thus require intermittent life-long administration. In contrast, insertion of healthy copies of the relevant gene or editing the disease locus in the genome to correct harmful mutations in stem cells is more likely to induce a permanent cure. Here we discuss the potential advantages and drawbacks of applying these technologies in patients with these genetic conditions. Given the severity of many genodermatoses, prevention of transmission to future generations remains an important goal including offering reproductive choices, such as preimplantation genetic testing, which can allow selection of an unaffected embryo for transfer to the uterus.
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Affiliation(s)
- Marie-Anne Morren
- Pediatric Dermatology Unit, Departments of Dermatology and Venereology and Pediatrics, University Hospital Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Eric Legius
- Department for Human Genetics, University Hospitals Leuven, KU Leuven, ERN Genturis and ERN Skin, Leuven, Belgium
| | - Fabienne Giuliano
- Department of Medical Genetics, University Hospital Lausanne, Lausanne, Switzerland
| | - Smail Hadj-Rabia
- Department of Pediatric Dermatology and Dermatology, National Reference Centre for Genodermatosis and Rare Diseases of the Skin (MAGEC), Hôpital Necker-Enfants Malades, and Assistance Publique-Hôpitaux de Paris, Université Paris Descartes, ERN Skin, Paris, France
| | - Daniel Hohl
- Department of Dermatology and Venereology, University Hospital Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Christine Bodemer
- Department of Pediatric Dermatology and Dermatology, National Reference Centre for Genodermatosis and Rare Diseases of the Skin (MAGEC), Hôpital Necker-Enfants Malades, and Assistance Publique-Hôpitaux de Paris, Université Paris Descartes, ERN Skin, Paris, France
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6
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Natsuga K, Furuta Y, Takashima S, Nohara T, Kosumi H, Mai Y, Higashi H, Ujiie H. Detection of revertant mosaicism in epidermolysis bullosa through Cas9‐targeted long‐read sequencing. Hum Mutat 2022; 43:529-536. [DOI: 10.1002/humu.24331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 12/14/2022]
Affiliation(s)
- Ken Natsuga
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Yoshikazu Furuta
- Division of Infection and Immunity, International Institute for Zoonosis Control Hokkaido University Sapporo Japan
| | - Shota Takashima
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Takuma Nohara
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Hideyuki Kosumi
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Yosuke Mai
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
| | - Hideaki Higashi
- Division of Infection and Immunity, International Institute for Zoonosis Control Hokkaido University Sapporo Japan
| | - Hideyuki Ujiie
- Department of Dermatology, Faculty of Medicine and Graduate School of Medicine Hokkaido University Sapporo Japan
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7
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Revertant Mosaicism in Epidermolysis Bullosa. Biomedicines 2022; 10:biomedicines10010114. [PMID: 35052793 PMCID: PMC8773552 DOI: 10.3390/biomedicines10010114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 12/29/2021] [Accepted: 01/05/2022] [Indexed: 12/20/2022] Open
Abstract
Epidermolysis bullosa (EB) is a group of genetic blistering diseases characterized by mechanically fragile skin and mucocutaneous involvement. Historically, disease management has focused on supportive care. The development of new genetic, cellular, and recombinant protein therapies has shown promise, and this review summarizes a unique gene and cell therapy phenomenon termed revertant mosaicism (RM). RM is the spontaneous correction of a disease-causing mutation. It has been reported in most EB subtypes, some with relatively high frequency, and has been observed in both keratinocytes and fibroblasts. RM manifests as identifiable patches of unaffected, blister-resistant skin and can occur through a variety of molecular mechanisms, including true back mutation, intragenic crossover, mitotic gene conversion, and second-site mutation. RM cells represent a powerful autologous platform for therapy, and leveraging RM cells as a therapeutic substrate may avoid the inherent mutational risks of gene therapy/editing. However, further examination of the genomic integrity and long-term functionality of RM-derived cells, as well in vivo testing of systemic therapies with RM cells, is required to realize the full therapeutic promise of naturally occurring RM in EB.
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8
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Olafsson S, Anderson CA. Somatic mutations provide important and unique insights into the biology of complex diseases. Trends Genet 2021; 37:872-881. [PMID: 34226062 DOI: 10.1016/j.tig.2021.06.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 10/20/2022]
Abstract
Somatic evolution of cells within the body is well known to lead to cancers. However, spread of somatic mutations within a tissue over time may also contribute to the pathogenesis of non-neoplastic diseases. Recent years have seen the publication of many studies aiming to characterize somatic evolution in healthy tissues. A logical next step is to extend such work to diseased conditions. As our understanding of the interplay between somatic mutations and non-neoplastic disease grows, opportunities for the joint study of germline and somatic variants will present themselves. Here, we present our thoughts on the utility of somatic mutations for understanding both the causes and consequences of common complex disease and the challenges that remain for the joint study of the soma and germline.
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Affiliation(s)
| | - Carl A Anderson
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK.
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9
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Abstract
Epidermolysis bullosa (EB) is an inherited, heterogeneous group of rare genetic dermatoses characterized by mucocutaneous fragility and blister formation, inducible by often minimal trauma. A broad phenotypic spectrum has been described, with potentially severe extracutaneous manifestations, morbidity and mortality. Over 30 subtypes are recognized, grouped into four major categories, based predominantly on the plane of cleavage within the skin and reflecting the underlying molecular abnormality: EB simplex, junctional EB, dystrophic EB and Kindler EB. The study of EB has led to seminal advances in our understanding of cutaneous biology. To date, pathogenetic mutations in 16 distinct genes have been implicated in EB, encoding proteins influencing cellular integrity and adhesion. Precise diagnosis is reliant on correlating clinical, electron microscopic and immunohistological features with mutational analyses. In the absence of curative treatment, multidisciplinary care is targeted towards minimizing the risk of blister formation, wound care, symptom relief and specific complications, the most feared of which - and also the leading cause of mortality - is squamous cell carcinoma. Preclinical advances in cell-based, protein replacement and gene therapies are paving the way for clinical successes with gene correction, raising hopes amongst patients and clinicians worldwide.
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10
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Nicolas G, Veltman JA. The role of de novo mutations in adult-onset neurodegenerative disorders. Acta Neuropathol 2019; 137:183-207. [PMID: 30478624 PMCID: PMC6513904 DOI: 10.1007/s00401-018-1939-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/14/2018] [Accepted: 11/14/2018] [Indexed: 12/13/2022]
Abstract
The genetic underpinnings of the most common adult-onset neurodegenerative disorders (AOND) are complex in majority of the cases. In some families, however, the disease can be inherited in a Mendelian fashion as an autosomal-dominant trait. Next to that, patients carrying mutations in the same disease genes have been reported despite a negative family history. Although challenging to demonstrate due to the late onset of the disease in most cases, the occurrence of de novo mutations can explain this sporadic presentation, as demonstrated for severe neurodevelopmental disorders. Exome or genome sequencing of patient-parent trios allows a hypothesis-free study of the role of de novo mutations in AOND and the discovery of novel disease genes. Another hypothesis that may explain a proportion of sporadic AOND cases is the occurrence of a de novo mutation after the fertilization of the oocyte (post-zygotic mutation) or even as a late-somatic mutation, restricted to the brain. Such somatic mutation hypothesis, that can be tested with the use of novel sequencing technologies, is fully compatible with the seeding and spreading mechanisms of the pathological proteins identified in most of these disorders. We review here the current knowledge and future perspectives on de novo mutations in known and novel candidate genes identified in the most common AONDs such as Alzheimer's disease, Parkinson's disease, the frontotemporal lobar degeneration spectrum and Prion disorders. Also, we review the first lessons learned from recent genomic studies of control and diseased brains and the challenges which remain to be addressed.
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Affiliation(s)
- Gaël Nicolas
- Normandie Univ, UNIROUEN, Inserm U1245 and Rouen University Hospital, Department of Genetics and CNR-MAJ, Normandy Center for Genomic and Personalized Medicine, 22, Boulevard Gambetta, 76000, 76031, Rouen Cedex, France.
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Joris A Veltman
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
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11
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van den Akker PC, Pasmooij AMG, Joenje H, Hofstra RMW, te Meerman GJ, Jonkman MF. A "late-but-fitter revertant cell" explains the high frequency of revertant mosaicism in epidermolysis bullosa. PLoS One 2018; 13:e0192994. [PMID: 29470523 PMCID: PMC5823395 DOI: 10.1371/journal.pone.0192994] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 02/03/2018] [Indexed: 12/20/2022] Open
Abstract
Revertant mosaicism, or "natural gene therapy", is the phenomenon in which germline mutations are corrected by somatic events. In recent years, revertant mosaicism has been identified in all major types of epidermolysis bullosa, the group of heritable blistering disorders caused by mutations in the genes encoding epidermal adhesion proteins. Moreover, revertant mosaicism appears to be present in all patients with a specific subtype of recessive epidermolysis bullosa. We therefore hypothesized that revertant mosaicism should be expected at least in all patients with recessive forms of epidermolysis bullosa. Naturally corrected, patient-own cells are of extreme interest for their promising therapeutic potential, and their presence in all patients would open exciting, new treatment perspectives to those patients. To test our hypothesis, we determined the probability that single nucleotide reversions occur in patients' skin using a mathematical developmental model. According to our model, reverse mutations are expected to occur frequently (estimated 216x) in each patient's skin. Reverse mutations should, however, occur early in embryogenesis to be able to drive the emergence of recognizable revertant patches, which is expected to occur in only one per ~10,000 patients. This underestimate, compared to our clinical observations, can be explained by the "late-but-fitter revertant cell" hypothesis: reverse mutations arise at later stages of development, but provide revertant cells with a selective growth advantage in vivo that drives the development of recognizable healthy skin patches. Our results can be extrapolated to any other organ with stem cell division numbers comparable to skin, which may offer novel future therapeutic options for other genetic conditions if these revertant cells can be identified and isolated.
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Affiliation(s)
- Peter C. van den Akker
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, the Netherlands
- University of Groningen, University Medical Center Groningen, Department of Dermatology, Groningen, the Netherlands
| | - Anna M. G. Pasmooij
- University of Groningen, University Medical Center Groningen, Department of Dermatology, Groningen, the Netherlands
| | - Hans Joenje
- Department of Clinical Genetics and the Cancer Center Amsterdam/VUmc Institute for Cancer and Immunology, VU University Medical Center, Amsterdam, the Netherlands
| | - Robert M. W. Hofstra
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Gerard J. te Meerman
- University of Groningen, University Medical Center Groningen, Department of Genetics, Groningen, the Netherlands
| | - Marcel F. Jonkman
- University of Groningen, University Medical Center Groningen, Department of Dermatology, Groningen, the Netherlands
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12
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Lim YH, Choate KA. Expanding the Mutation Spectrum of Ichthyosis with Confetti. J Invest Dermatol 2017; 136:1941-1943. [PMID: 27664712 DOI: 10.1016/j.jid.2016.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 07/09/2016] [Indexed: 11/16/2022]
Abstract
Ichthyosis with confetti is a rare, autosomal dominant disorder caused by frameshift mutations in KRT10 or KRT1 and characterized by the development of white, genetically revertant macules in red, diseased skin. All cases result from mutations affecting the tail domains of keratin-10 or keratin-1, and Suzuki et al. expand the mutation spectrum for ichthyosis with confetti caused by mutations in KRT1, showing that a polyarginine frameshift in the keratin-1 tail can also cause this disorder.
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Affiliation(s)
- Young H Lim
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Keith A Choate
- Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA.
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13
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Federico C, Dugo K, Bruno F, Longo AM, Grillo A, Saccone S. Somatic mosaicism with reversion to normality of a mutated transthyretin allele related to a familial amyloidotic polyneuropathy. Hum Genet 2017; 136:867-873. [DOI: 10.1007/s00439-017-1810-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 05/10/2017] [Indexed: 12/31/2022]
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14
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Happle R. The Molecular Revolution in Cutaneous Biology: Era of Mosaicism. J Invest Dermatol 2017; 137:e73-e77. [PMID: 28411850 DOI: 10.1016/j.jid.2016.03.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 02/08/2016] [Accepted: 03/02/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Rudolf Happle
- Department of Dermatology, Freiburg University Medical Center, Freiburg, Germany.
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15
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Yenamandra VK, Vellarikkal SK, Kumar M, Chowdhury MR, Jayarajan R, Verma A, Scaria V, Sivasubbu S, Ray SB, Dinda AK, Kabra M, Kaur P, Sharma VK, Sethuraman G. Application of whole exome sequencing in elucidating the phenotype and genotype spectrum of junctional epidermolysis bullosa: A preliminary experience of a tertiary care centre in India. J Dermatol Sci 2017; 86:30-36. [PMID: 28087116 DOI: 10.1016/j.jdermsci.2016.12.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 12/20/2016] [Accepted: 12/28/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND Junctional epidermolysis bullosa (JEB) is a diverse group of genodermatoses associated with extreme skin fragility. Despite several well-characterized genetic studies, molecular diagnosis of this heterogeneous group is still challenging. Recent advances in the field of genomics have seen the successful implementation of whole exome sequencing (WES) as a fast and efficient diagnostic strategy in several genodermatoses. OBJECTIVE In view of the scarcity and need of molecular studies for JEB in India, we sought to explore the potential of WES in understanding the mutational spectrum of this rare, in certain subtypes lethal, sub-group of EB. METHODS WES was performed using genomic DNA from each case of EB, followed by massively parallel sequencing. Resulting reads were mapped to the human reference genome hg19. Sanger sequencing subsequently confirmed the potentially pathogenic mutations. RESULTS Overall, four unrelated families (6 patients) of JEB with a highly variable clinical presentation including a rare case of LOC syndrome were studied. WES revealed 4 variations in 3 genes (LAMA3, LAMB3 and COL17A1) that are implicated in JEB. None of the variations were recurrent. In addition we proposed the probable molecular consequence of a missense mutation on the structure-function relationship of lamininβ3 protein through computational modeling studies. CONCLUSIONS Being the first report documenting the phenotype-genotype correlations of JEB patients from India, our preliminary experience with WES is clearly encouraging and serves as a nidus for future large-scale molecular studies to actively identify and understand JEB patients in Indian population.
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Affiliation(s)
- Vamsi K Yenamandra
- Departments of Dermatology & Venereology, All India Institute of Medical Sciences, New Delhi, India
| | - Shamsudheen K Vellarikkal
- CSIR-Institute of Genomics & Integrative Biology, Mathura Road, New Delhi, India; Academy of Scientific and Innovative Research, CSIR, India
| | - Manoj Kumar
- Departments of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Madhumita R Chowdhury
- Departments of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Rijith Jayarajan
- CSIR-Institute of Genomics & Integrative Biology, Mathura Road, New Delhi, India
| | - Ankit Verma
- CSIR-Institute of Genomics & Integrative Biology, Mathura Road, New Delhi, India
| | - Vinod Scaria
- CSIR-Institute of Genomics & Integrative Biology, Mathura Road, New Delhi, India; Academy of Scientific and Innovative Research, CSIR, India
| | - Sridhar Sivasubbu
- CSIR-Institute of Genomics & Integrative Biology, Mathura Road, New Delhi, India; Academy of Scientific and Innovative Research, CSIR, India
| | - Subrata B Ray
- Departments of Anatomy, All India Institute of Medical Sciences, New Delhi, India
| | - Amit K Dinda
- Departments of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Madhulika Kabra
- Departments of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Punit Kaur
- Departments of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Vinod K Sharma
- Departments of Dermatology & Venereology, All India Institute of Medical Sciences, New Delhi, India
| | - Gomathy Sethuraman
- Departments of Dermatology & Venereology, All India Institute of Medical Sciences, New Delhi, India.
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Revertant mosaicism in genodermatoses. Cell Mol Life Sci 2017; 74:2229-2238. [PMID: 28168442 DOI: 10.1007/s00018-017-2468-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 12/20/2022]
Abstract
Inherited monogenic skin disorders include blistering disorders, inflammatory disorders, and disorders of differentiation or development. In most cases, the skin is broadly involved throughout the affected individual's lifetime, but rarely, appearance of normal skin clones has been described. In these cases of revertant mosaicism, cells undergo spontaneous correction to ameliorate the effects of genetic mutation. While targeted reversion of genetic mutation would have tremendous therapeutic value, the mechanisms of reversion in the skin are poorly understood. In this review, we provide an overview of genodermatoses that demonstrate widespread reversion and their corrective mechanisms, as well as the current research aimed to understand this "natural gene therapy".
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17
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Rashidghamat E, McGrath JA. Novel and emerging therapies in the treatment of recessive dystrophic epidermolysis bullosa. Intractable Rare Dis Res 2017; 6:6-20. [PMID: 28357176 PMCID: PMC5359356 DOI: 10.5582/irdr.2017.01005] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Epidermolysis bullosa (EB) is a clinically and genetically heterogeneous group of inherited blistering diseases that affects ∼ 500,000 people worldwide. Clinically, individuals with EB have fragile skin and are susceptible to blistering following minimal trauma, with mucous membrane and other organ involvement in some subtypes. Within the spectrum of EB, ∼ 5% of affected individuals have the clinically more severe recessive dystrophic (RDEB) variant with a prevalence of 8 per one million of the population. RDEB is caused by loss-of-function mutations in the type VII collagen gene, COL7A1, which leads to reduced or absent type VII collagen (C7) and a paucity of structurally effective anchoring fibrils at the dermal-epidermal junction (DEJ). Currently, there is no cure for RDEB, although considerable progress has been made in testing novel treatments including gene therapy (lentiviral and gamma retroviral vectors for COL7A1 supplementation in keratinocytes and fibroblasts), as well as cell therapy (use of allogeneic fibroblasts, mesenchymal stromal cells (MSCs), and bone marrow transplantation (BMT)). Here, we review current treatment modalities available as well as novel and emerging therapies in the treatment of RDEB. Clinical trials of new translational therapies in RDEB offer hope for improved clinical management of patients as well as generating broader lessons for regenerative medicine that could be applicable to other inherited or acquired abnormalities of wound healing or scarring.
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Affiliation(s)
- Ellie Rashidghamat
- St. John's Institute of Dermatology, King's College London, London, United Kingdom
| | - John A. McGrath
- St. John's Institute of Dermatology, King's College London, London, United Kingdom
- Address correspondence to: Dr. John A. McGrath, Dermatology Research Laboratories, Floor 9 Tower Wing, Guy's Hospital, Great Maze Pond, London SE1 9RT, United Kingdom. E-mail:
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18
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Bornert O, Peking P, Bremer J, Koller U, van den Akker PC, Aartsma-Rus A, Pasmooij AMG, Murauer EM, Nyström A. RNA-based therapies for genodermatoses. Exp Dermatol 2017; 26:3-10. [PMID: 27376675 PMCID: PMC5593095 DOI: 10.1111/exd.13141] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2016] [Indexed: 12/14/2022]
Abstract
Genetic disorders affecting the skin, genodermatoses, constitute a large and heterogeneous group of diseases, for which treatment is generally limited to management of symptoms. RNA-based therapies are emerging as a powerful tool to treat genodermatoses. In this review, we discuss in detail RNA splicing modulation by antisense oligonucleotides and RNA trans-splicing, transcript replacement and genome editing by in vitro-transcribed mRNAs, and gene knockdown by small interfering RNA and antisense oligonucleotides. We present the current state of these therapeutic approaches and critically discuss their opportunities, limitations and the challenges that remain to be solved. The aim of this review was to set the stage for the development of new and better therapies to improve the lives of patients and families affected by a genodermatosis.
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Affiliation(s)
- Olivier Bornert
- Department of Dermatology, Medical Center – University of
Freiburg, Freiburg, Germany
| | - Patricia Peking
- EB House Austria, Research Program for Molecular Therapy of
Genodermatoses, Department of Dermatology, University Hospital of the Paracelsus
Medical University, Salzburg, Austria
| | - Jeroen Bremer
- Department of Dermatology, University Medical Center Groningen,
University of Groningen, Groningen, The Netherlands
| | - Ulrich Koller
- EB House Austria, Research Program for Molecular Therapy of
Genodermatoses, Department of Dermatology, University Hospital of the Paracelsus
Medical University, Salzburg, Austria
| | - Peter C. van den Akker
- Department of Dermatology, University Medical Center Groningen,
University of Groningen, Groningen, The Netherlands
- Department of Genetics, University Medical Center Groningen,
University of Groningen, Groningen, The Netherlands
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center,
Leiden, The Netherlands
| | - Anna M. G. Pasmooij
- Department of Dermatology, University Medical Center Groningen,
University of Groningen, Groningen, The Netherlands
| | - Eva M. Murauer
- EB House Austria, Research Program for Molecular Therapy of
Genodermatoses, Department of Dermatology, University Hospital of the Paracelsus
Medical University, Salzburg, Austria
| | - Alexander Nyström
- Department of Dermatology, Medical Center – University of
Freiburg, Freiburg, Germany
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19
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Abstract
The term epidermolysis bullosa (EB) includes a group of rare genodermatoses characterized by mutational impairment of the structural and functional integrity of intraepidermal adhesion and dermoepidermal anchorage. Clinically, these disorders are marked by increased skin fragility as well as characteristic mechanically inducible blisters on the skin and mucous membranes. Extracutaneous manifestations and their complications in other epithelialized organs render EB a multi-system disease associated with significant morbidity and mortality. Cornerstones of a dynamically changing healthcare structure include precise and early diagnosis; coordinated, multidisciplinary, individually adjusted patient care at specialized centers; optimized symptomatic therapies; and access to research-based, potentially curative therapeutic strategies.
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Affiliation(s)
- Martin Laimer
- Department of Dermatology, Paracelsus Medical University Salzburg, Austria
| | | | - Johann W Bauer
- Department of Dermatology, Paracelsus Medical University Salzburg, Austria
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20
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Liu CC, Lin SP, Hsu HS, Yang SH, Lin CH, Yang MH, Hung MC, Hung SC. Suspension survival mediated by PP2A-STAT3-Col XVII determines tumour initiation and metastasis in cancer stem cells. Nat Commun 2016; 7:11798. [PMID: 27306323 PMCID: PMC4912642 DOI: 10.1038/ncomms11798] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 04/28/2016] [Indexed: 12/27/2022] Open
Abstract
Targeting tumour-initiating cells (TICs) would lead to new therapies to cure cancer. We previously demonstrated that TICs have the capacity to survive under suspension conditions, while other cells undergo anoikis. Here we show that TICs exhibit increased phosphorylation levels of S727STAT3 because of PP2A inactivation. Collagen 17 gene expression is upregulated in a STAT3-dependent manner, which also stabilizes laminin 5 and engages cells to form hemidesmosome-like junctions in response. Blocking the PP2A-S727STAT3-collagen 17 pathway inhibits the suspension survival of TICs and their ability to form tumours in mice, while activation of the same pathway increases the suspension survival and tumour-initiation capacities of bulk cancer cells. The S727STAT3 phosphorylation levels correlate with collagen 17 expression in colon tumour samples, and correlate inversely with survival. Finally, this signalling axis enhances the ability of TIC to form tumours in mouse models of malignant lung cancer pleural effusion and spontaneous colon cancer metastasis.
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Affiliation(s)
- Chen-Chi Liu
- Institute of Clinical Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Shih-Pei Lin
- Institute of Clinical Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Han-Shui Hsu
- Institute of Emergency and Critical Care Medicine, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan
- Department of Surgery, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Shung-Haur Yang
- Department of Surgery, Taipei Veterans General Hospital, Taipei 112, Taiwan
- Department of Surgery, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Chiu-Hua Lin
- Institute of Clinical Medicine, National Yang-Ming University, Taipei 112, Taiwan
| | - Muh-Hwa Yang
- Institute of Clinical Medicine, National Yang-Ming University, Taipei 112, Taiwan
- Department of Oncology, Taipei Veterans General Hospital, Taipei 112, Taiwan
| | - Mien-Chie Hung
- Graduate Institute of Cancer Biology, College of Medicine, Center for Molecular Medicine, China Medical University and Hospital, Taichung 404, Taiwan
- Department of Molecular and Cellular Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
| | - Shih-Chieh Hung
- Institute of Clinical Medicine, National Yang-Ming University, Taipei 112, Taiwan
- Department of Medical Research and Education, Stem Cell Laboratory, Taipei Veterans General Hospital, Taipei 112, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan
- Department of Orthopedics, Integrative Stem Cell Center, China Medical University Hospital, Taichung 404, Taiwan
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung 404, Taiwan
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21
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Affiliation(s)
- Martin Laimer
- Universitätsklinik für Dermatologie, Paracelsus Medizinische Privatuniversität Salzburg, Österreich
| | - Christine Prodinger
- Universitätsklinik für Dermatologie, Paracelsus Medizinische Privatuniversität Salzburg, Österreich
| | - Johann W. Bauer
- Universitätsklinik für Dermatologie, Paracelsus Medizinische Privatuniversität Salzburg, Österreich
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22
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Musso N, Caronia FP, Castorina S, Lo Monte AI, Barresi V, Condorelli DF. Somatic loss of an EXT2 gene mutation during malignant progression in a patient with hereditary multiple osteochondromas. Cancer Genet 2015; 208:62-7. [PMID: 25744876 DOI: 10.1016/j.cancergen.2015.01.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/19/2014] [Accepted: 01/11/2015] [Indexed: 10/24/2022]
Abstract
Multiple osteochondromas (MO) is an autosomal-dominant skeletal disorder caused by mutations in the exostosin-1 (EXT1) or exostosin-2 (EXT2) genes. In this study, we report the analysis of the mutational status of the EXT2 gene in tumor samples derived from a patient affected by hereditary MO, documenting the somatic loss of the germline mutation in a giant chondrosarcoma and in a rapidly growing osteochondroma. The sequencing of all exons and exon-intron junctions of the EXT1 and EXT2 genes from blood DNA of the proband did not reveal any mutation in the EXT1 gene but did demonstrate the presence of the transition point mutation c.67C > T in the EXT2 gene, determining the introduction of a stop codon in the coding sequence (p.Arg23*). A mutational analysis of other members of the family and the presence of osteochondromas in the metaphysis of long bones confirmed the diagnosis of hereditary multiple osteochondromas. Direct sequencing from DNA extracted from different sites of two tumor samples (a small rapidly growing osteochondroma and a giant peripheral secondary chondrosarcoma, each located at different chondrocostal junctions) revealed the loss of the germline EXT2 mutation. Analysis of microsatellite polymorphic markers in the 11p region harboring the EXT2 gene did not reveal any loss of heterozygosity. This observation supports a recent model of sarcomagenesis in which osteochondroma cells bear EXT homozygous inactivation, whereas chondrosarcoma-initiating cells are EXT-expressing cells.
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Affiliation(s)
- Nicolò Musso
- Scuola Superiore di Catania, University of Catania, Catania, Italy; Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, Catania, Italy
| | - Francesco Paolo Caronia
- Dipartimento di Chirurgia Toracica, Centro Clinico e Diagnostico "G.B Morgagni", Catania, Italy
| | - Sergio Castorina
- Dipartimento di Chirurgia Toracica, Centro Clinico e Diagnostico "G.B Morgagni", Catania, Italy; Department of Biomedical and Biotechnological Sciences, Section of Human Anatomy and Histology, University of Catania, Catania, Italy
| | | | - Vincenza Barresi
- Scuola Superiore di Catania, University of Catania, Catania, Italy; Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, Catania, Italy
| | - Daniele Filippo Condorelli
- Scuola Superiore di Catania, University of Catania, Catania, Italy; Department of Biomedical and Biotechnological Sciences, Section of Medical Biochemistry, University of Catania, Catania, Italy.
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23
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Turcan I, Jonkman MF. Blistering disease: insight from the hemidesmosome and other components of the dermal-epidermal junction. Cell Tissue Res 2014; 360:545-69. [PMID: 25502077 DOI: 10.1007/s00441-014-2021-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 09/25/2014] [Indexed: 02/07/2023]
Abstract
The hemidesmosome is a specialized transmembrane complex that mediates the binding of epithelial cells to the underlying basement membrane. In the skin, this multiprotein structure can be regarded as the chief adhesion unit at the site of the dermal-epidermal junction. Focal adhesions are additional specialized attachment structures located between hemidesmosomes. The integrity of the skin relies on well-assembled and functional hemidesmosomes and focal adhesions (also known as integrin adhesomes). However, if these adhesion structures are impaired, e.g., as a result of circulating autoantibodies or inherited genetic mutations, the mechanical strength of the skin is compromised, leading to blistering and/or tissue inflammation. A particular clinical presentation emerges subject to the molecule that is targeted. None of these junctional complexes are simply compounds of adhesion molecules; they also play a significant role in signalling pathways involved in the differentiation and migration of epithelial cells such as during wound healing and in tumour invasion. We summarize current knowledge about hereditary and acquired blistering diseases emerging from pathologies of the hemidesmosome and its neighbouring proteins as components of the dermal-epidermal junction.
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Affiliation(s)
- Iana Turcan
- Centre for Blistering Diseases, Department of Dermatology, University Medical Centre Groningen, University of Groningen, P.O. Box 30.001, 9700 RB, Groningen, The Netherlands,
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24
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Umegaki-Arao N, Pasmooij AMG, Itoh M, Cerise JE, Guo Z, Levy B, Gostyński A, Rothman LR, Jonkman MF, Christiano AM. Induced pluripotent stem cells from human revertant keratinocytes for the treatment of epidermolysis bullosa. Sci Transl Med 2014; 6:264ra164. [PMID: 25429057 DOI: 10.1126/scitranslmed.3009342] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Revertant mosaicism is a naturally occurring phenomenon involving spontaneous correction of a pathogenic gene mutation in a somatic cell. It has been observed in several genetic diseases, including epidermolysis bullosa (EB), a group of inherited skin disorders characterized by blistering and scarring. Induced pluripotent stem cells (iPSCs), generated from fibroblasts or keratinocytes, have been proposed as a treatment for EB. However, this requires genome editing to correct the mutations, and, in gene therapy, efficiency of targeted gene correction and deleterious genomic modifications are still limitations of translation. We demonstrate the generation of iPSCs from revertant keratinocytes of a junctional EB patient with compound heterozygous COL17A1 mutations. These revertant iPSCs were then differentiated into naturally genetically corrected keratinocytes that expressed type XVII collagen (Col17). Gene expression profiling showed a strong correlation between gene expression in revertant iPSC-derived keratinocytes and the original revertant keratinocytes, indicating the successful differentiation of iPSCs into the keratinocyte lineage. Revertant-iPSC keratinocytes were then used to create in vitro three-dimensional skin equivalents and reconstitute human skin in vivo in mice, both of which expressed Col17 in the basal layer. Therefore, revertant keratinocytes may be a viable source of spontaneously gene-corrected cells for developing iPSC-based therapeutic approaches in EB.
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Affiliation(s)
| | - Anna M G Pasmooij
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, the Netherlands
| | - Munenari Itoh
- Department of Dermatology, Columbia University, New York, NY 10032, USA. Department of Dermatology, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Jane E Cerise
- Department of Dermatology, Columbia University, New York, NY 10032, USA
| | - Zongyou Guo
- Department of Dermatology, Columbia University, New York, NY 10032, USA
| | - Brynn Levy
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Antoni Gostyński
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, the Netherlands
| | - Lisa R Rothman
- Department of Dermatology, Columbia University, New York, NY 10032, USA
| | - Marcel F Jonkman
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen 9700 RB, the Netherlands
| | - Angela M Christiano
- Department of Dermatology, Columbia University, New York, NY 10032, USA. Department of Genetics and Development, Columbia University, New York, NY 10032, USA.
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25
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Abstract
The skin is composed of a variety of cell types expressing specific molecules and possessing different properties that facilitate the complex interactions and intercellular communication essential for maintaining the structural integrity of the skin. Importantly, a single mutation in one of these molecules can disrupt the entire organization and function of these essential networks, leading to cell separation, blistering, and other striking phenotypes observed in inherited skin diseases. Over the past several decades, the genetic basis of many monogenic skin diseases has been elucidated using classical genetic techniques. Importantly, the findings from these studies has shed light onto the many classes of molecules and essential genetic as well as molecular interactions that lend the skin its rigid, yet flexible properties. With the advent of the human genome project, next-generation sequencing techniques, as well as several other recently developed methods, tremendous progress has been made in dissecting the genetic architecture of complex, non-Mendelian skin diseases.
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Affiliation(s)
- Gina M DeStefano
- Department of Genetics and Development, Columbia University, New York, New York 10032
| | - Angela M Christiano
- Department of Genetics and Development, Columbia University, New York, New York 10032 Department of Dermatology, Columbia University, New York, New York 10032
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26
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Albanova VI, Chikin VV, Epishev RV. Revisited diagnostics of hereditary epidermolysis bullosa. VESTNIK DERMATOLOGII I VENEROLOGII 2014. [DOI: 10.25208/0042-4609-2014-90-3-53-59] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Hereditary epidermolysis bullosa is a big group of hereditary diseases with the main manifestations in the form of blisters on the skin and mucous coat after slight mechanical injuries. It is not always possible to diagnose this disease based on the clinical picture. The article discusses current laboratory diagnostics methods for hereditary epidermolysis bullosa including immunofluorescence antigen mapping (IFM), transmission electron microscopy (TEM) and genetic analysis (molecular or DNA diagnostics) as well as their advantages and disadvantages. TEM determines the micro splitting level and nature of ultrafine changes in the area of the dermoepidermal junction; at the same time, such tests need special expensive equipment. Substantial experience is also needed to analyze the resulting submicroscopic images. IFM determines whether expression of the affected protein related to the disease development is reduced or absent; however, invalid (false positive or false negative) results can be obtained in patients with the reduced expression of the affected protein. Genetic analysis plays a key role for prenatal diagnostics. Therefore, to make an exact diagnosis of hereditary epidermolysis bullosa, it is expedient to apply IFM, TEM and genetic analysis. The need to set an exact diagnosis of the disease is related to the fact that the promising treatment methods being currently developed are aimed at treating patients with certain forms of the disease.
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27
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Abstract
Genetic skin fragility manifests with diminished resistance of the skin and mucous membranes to external mechanical forces and with skin blistering, erosions, and painful wounds as clinical features. Skin fragility disorders, collectively called epidermolysis bullosa, are caused by mutations in 18 distinct genes that encode proteins involved in epidermal integrity and dermal-epidermal adhesion. The genetic spectrum, along with environmental and genetic modifiers, creates a large number of clinical phenotypes, spanning from minor localized lesions to severe generalized blistering, secondary skin cancer, or early demise resulting from extensive loss of the epidermis. Laboratory investigations of skin fragility have greatly augmented our understanding of genotype-phenotype correlations in epidermolysis bullosa and have also advanced skin biology in general. Current translational research concentrates on the development of biologically valid treatments with therapeutic genes, cells, proteins, or small-molecule compounds in preclinical settings or human pilot trials.
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Affiliation(s)
- Cristina Has
- Department of Dermatology, Medical Center-University of Freiburg, Freiburg 79104, Germany;
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28
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Mechanisms of natural gene therapy in dystrophic epidermolysis bullosa. J Invest Dermatol 2014; 134:2097-2104. [PMID: 24577406 DOI: 10.1038/jid.2014.118] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 12/27/2013] [Accepted: 01/21/2014] [Indexed: 01/25/2023]
Abstract
Revertant mosaicism has been reported in several inherited diseases, including the genetic skin fragility disorder epidermolysis bullosa (EB). Here, we describe the largest cohort of seven patients with revertant mosaicism and dystrophic EB (DEB), associated with mutations in the COL7A1 gene, and determine the underlying molecular mechanisms. We show that revertant mosaicism occurs both in autosomal dominantly and recessively inherited DEB. We found that null mutations resulting in complete loss of collagen VII and severe disease, as well as missense or splice-site mutations associated with some preserved collagen VII function and a milder phenotype, were corrected by revertant mosaicism. The mutation, subtype, and severity of the disease are thus not decisive for the presence of revertant mosaicism. Although collagen VII is synthesized and secreted by both keratinocytes and fibroblasts, evidence for reversion was only found in keratinocytes. The reversion mechanisms included back mutations/mitotic recombinations in 70% of the cases and second-site mutations affecting splicing in 30%. We conclude that revertant mosaicism is more common than previously assumed in patients with DEB, and our findings will have implications for future therapeutic strategies using the patient's naturally corrected cells as a source for cell-based therapies.
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29
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Gostyński A, Llames S, García M, Escamez MJ, Martinez-Santamaria L, Nijenhuis M, Meana A, Pas HH, Larcher F, Pasmooij AMG, Jonkman MF, Del Rio M. Long-term survival of type XVII collagen revertant cells in an animal model of revertant cell therapy. J Invest Dermatol 2014; 134:571-574. [PMID: 23884316 DOI: 10.1038/jid.2013.308] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Antoni Gostyński
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Sara Llames
- Tissue Engineering Laboratory, CCST-PA and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Oviedo, Spain
| | - Marta García
- Regenerative Medicine Unit, CIEMAT and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Madrid, Spain; Department of Bioengineering, Universidad Carlos III de Madrid, Madrid, Spain
| | - María J Escamez
- Regenerative Medicine Unit, CIEMAT and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Madrid, Spain
| | - Lucía Martinez-Santamaria
- Regenerative Medicine Unit, CIEMAT and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Madrid, Spain; Department of Bioengineering, Universidad Carlos III de Madrid, Madrid, Spain
| | - Miranda Nijenhuis
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Alvaro Meana
- Tissue Engineering Laboratory, CCST-PA and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Oviedo, Spain
| | - Hendri H Pas
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Fernando Larcher
- Regenerative Medicine Unit, CIEMAT and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Madrid, Spain
| | - Anna M G Pasmooij
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marcel F Jonkman
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marcela Del Rio
- Regenerative Medicine Unit, CIEMAT and Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER U714), Madrid, Spain; Department of Bioengineering, Universidad Carlos III de Madrid, Madrid, Spain
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30
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Gostyński A, Pasmooij AMG, Del Rio M, Diercks GF, Pas HH, Jonkman MF. Pigmentation and melanocyte supply to the epidermis depend on type XVII collagen. Exp Dermatol 2014; 23:130-2. [PMID: 24330315 DOI: 10.1111/exd.12304] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2013] [Indexed: 12/16/2023]
Abstract
Genetic deficiency of type XVII collagen (C17), laminin-332 or type VII collagen causes epidermolysis bullosa (EB). Spontaneous correction of the deficiency, also known as revertant mosaicism, is caused by a second somatic mutation that restores protein expression resulting in clinically healthy (revertant) patches surrounded by fragile (mutant) skin. Interestingly, in some patients, patches of revertant skin show hyperpigmentation. To study the possible role of affected proteins in pigmentation and melanocyte distribution, we investigated clinical documentation and skin biopsy specimens of 13 revertant EB patients having correcting mutations in the COL17A1, LAMB3 or COL7A1 genes. Analysis revealed that lack of C17 led to decreased melanin intensity and melanocyte density in the epidermis when compared with the revertant patches. Reversions of LAMB3 and COL7A1 in keratinocytes did not influence clinical pigmentation or density of melanocytes. We conclude that in human skin, melanocyte supply to the epidermis depends on C17 expression in keratinocytes.
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Affiliation(s)
- Antoni Gostyński
- Center for Blistering Diseases, Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
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31
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Carulli S, Contin R, De Rosa L, Pellegrini G, De Luca M. The long and winding road that leads to a cure for epidermolysis bullosa. Regen Med 2013; 8:467-81. [DOI: 10.2217/rme.13.33] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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32
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Kuijpers TW, van Leeuwen EMM, Barendregt BH, Klarenbeek P, aan de Kerk DJ, Baars PA, Jansen MH, de Vries N, van Lier RAW, van der Burg M. A reversion of an IL2RG mutation in combined immunodeficiency providing competitive advantage to the majority of CD8+ T cells. Haematologica 2013; 98:1030-8. [PMID: 23403317 DOI: 10.3324/haematol.2012.077511] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Mutations in the common gamma chain (γc, CD132, encoded by the IL2RG gene) can lead to B(+)T(-)NK(-) X-linked severe combined immunodeficiency, as a consequence of unresponsiveness to γc-cytokines such as interleukins-2, -7 and -15. Hypomorphic mutations in CD132 may cause combined immunodeficiencies with a variety of clinical presentations. We analyzed peripheral blood mononuclear cells of a 6-year-old boy with normal lymphocyte counts, who suffered from recurrent pneumonia and disseminated mollusca contagiosa. Since proliferative responses of T cells and NK cells to γc -cytokines were severely impaired, we performed IL2RG gene analysis, showing a heterozygous mutation in the presence of a single X-chromosome. Interestingly, an IL2RG reversion to normal predominated in both naïve and antigen-primed CD8(+) T cells and increased over time. Only the revertant CD8(+) T cells showed normal expression of CD132 and the various CD8(+) T cell populations had a different T-cell receptor repertoire. Finally, a fraction of γδ(+) T cells and differentiated CD4(+)CD27(-) effector-memory T cells carried the reversion, whereas NK or B cells were repeatedly negative. In conclusion, in a patient with a novel IL2RG mutation, gene-reverted CD8(+) T cells accumulated over time. Our data indicate that selective outgrowth of particular T-cell subsets may occur following reversion at the level of committed T progenitor cells.
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Affiliation(s)
- Taco W Kuijpers
- Emma Children's Hospital, Academic Medical Center (AMC), Amsterdam, The Netherlands
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33
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Abstract
Laser Dissection Microscopy (LDM) is a valuable technique to identify the genetic event that underlies cutaneous mosaicism. Isolation of a selected cell population is key to the detection of a somatic mutation. Advantages of the LDM technique are that stored skin biopsies can be analyzed without the necessity of culturing cells. Here, we describe the preparation of skin sections and cells for LDM, followed by dissection, and subsequent DNA and RNA analysis in order to detect the underlying somatic mutation.
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Affiliation(s)
- Anna M G Pasmooij
- Department of Dermatology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
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Affiliation(s)
- Anna M G Pasmooij
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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Pasmooij AMG, Nijenhuis M, Brander R, Jonkman MF. Natural gene therapy may occur in all patients with generalized non-Herlitz junctional epidermolysis bullosa with COL17A1 mutations. J Invest Dermatol 2012; 132:1374-83. [PMID: 22318390 DOI: 10.1038/jid.2011.477] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mutations in the type XVII collagen gene (COL17A1) result in the blistering disorder non-Herlitz junctional epidermolysis bullosa (JEB-nH). The incidence of revertant mosaicism, also called "natural gene therapy", was identified in a cohort of 14 patients with JEB-nH caused by COL17A1 mutations in the Netherlands. Five different in vivo reversions, all correcting the germ-line COL17A1 mutation c.2237delG in exon 30, were found in four mosaic JEB-nH patients. The correcting DNA changes involved a wide variety of somatic mutations, from which an indel mutation (c.2228-101_2263+70delins15) and a large deletion of 2,165 base pairs (c.2227+153_2336-318del) have not been previously observed in patients with revertant mosaicism. Our results show that there is no preference for a repair mechanism. Moreover, revertant mosaicism was confirmed on a DNA level in 6 out of 10 generalized JEB-nH patients. Further, photo-material and clinical history of the other four generalized JEB-nH patients demonstrated that each patient has revertant skin patches. In contrast, revertant mosaicism was not detected in the four localized JEB-nH patients. The fact that so many, if not all, generalized JEB-nH COL17A1 patients have revertant patches offers opportunities for cell therapies in which the patient's own naturally corrected cells are used as a source.
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Affiliation(s)
- Anna M G Pasmooij
- Department of Dermatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
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36
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Abstract
In this issue, Lai-Cheong et al. report a patient with Kindler syndrome who showed revertant mosaicism: a patch of normal-looking skin attributable to a reverse mutation. The molecular basis of the reverted patch appeared to be the deletion of a duplicated cytosine, thus restoring the reading frame of FERMT1 transcripts. This finding further pushes the frontier of revertant mosaicism, a phenomenon of spontaneous gene repair, which can be seen with the naked eye in skin.
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Abstract
Rapid advances in next-generation sequencing technology are revolutionizing approaches to genomic and epigenomic studies of skin. Deep sequencing of cutaneous malignancies reveals heavily mutagenized genomes with large numbers of low-prevalence mutations and multiple resistance mechanisms to targeted therapies. Next-generation sequencing approaches have already paid rich dividends in identifying the genetic causes of dermatologic disease, both in heritable mutations and the somatic aberrations that underlie cutaneous mosaicism. Although epigenetic alterations clearly influence tumorigenesis, pluripotent stem cell biology, and epidermal cell lineage decisions, labor and cost-intensive approaches long delayed a genome-scale perspective. New insights into epigenomic mechanisms in skin disease should arise from the accelerating assessment of histone modification, DNA methylation, and related gene expression signatures.
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Affiliation(s)
- Jeffrey B Cheng
- Department of Dermatology, University of California, San Francisco, San Francisco, California 94143, USA
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Lai-Cheong JE, McGrath JA, Uitto J. Revertant mosaicism in skin: natural gene therapy. Trends Mol Med 2010; 17:140-8. [PMID: 21195026 DOI: 10.1016/j.molmed.2010.11.003] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/16/2010] [Accepted: 11/16/2010] [Indexed: 01/05/2023]
Abstract
Revertant mosaicism is a naturally occurring phenomenon involving spontaneous correction of a pathogenic mutation in a somatic cell. Recent studies suggest that it is not a rare event and that it could be clinically relevant to phenotypic expression and patient treatment. Indeed, revertant cell therapy represents a potential 'natural gene therapy' because in vivo reversion obviates the need for further genetic correction. Revertant mosaicism has been observed in several inherited conditions, including epidermolysis bullosa, a heterogeneous group of blistering skin disorders. These diseases provide a useful model for studying revertant mosaicism because of the visual and accessible nature of skin. This overview highlights the latest developments in revertant mosaicism and the translational implications germane to heritable skin disorders.
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Affiliation(s)
- Joey E Lai-Cheong
- St John's Institute of Dermatology, Division of Genetics and Molecular Medicine, Floor 9 Tower Wing, King's College London (Guy's Campus), London SE1 9RT, United Kingdom.
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40
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Affiliation(s)
- Brian R Davis
- Centre for Stem Cell Research, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, TX 77030, USA.
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Somatic gene mutation and human disease other than cancer: An update. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2010; 705:96-106. [DOI: 10.1016/j.mrrev.2010.04.002] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 03/29/2010] [Accepted: 04/08/2010] [Indexed: 12/24/2022]
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Pasmooij AM, Garcia M, Escamez MJ, Miranda Nijenhuis A, Azon A, Cuadrado-Corrales N, Jonkman MF, Del Rio M. Revertant Mosaicism Due to a Second-Site Mutation in COL7A1 in a Patient with Recessive Dystrophic Epidermolysis Bullosa. J Invest Dermatol 2010; 130:2407-11. [DOI: 10.1038/jid.2010.163] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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43
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Choate KA, Lu Y, Zhou J, Choi M, Elias PM, Farhi A, Nelson-Williams C, Crumrine D, Williams ML, Nopper AJ, Bree A, Milstone LM, Lifton RP. Mitotic recombination in patients with ichthyosis causes reversion of dominant mutations in KRT10. Science 2010; 330:94-7. [PMID: 20798280 DOI: 10.1126/science.1192280] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Somatic loss of wild-type alleles can produce disease traits such as neoplasia. Conversely, somatic loss of disease-causing mutations can revert phenotypes; however, these events are infrequently observed. Here we show that ichthyosis with confetti, a severe, sporadic skin disease in humans, is associated with thousands of revertant clones of normal skin that arise from loss of heterozygosity on chromosome 17q via mitotic recombination. This allowed us to map and identify disease-causing mutations in the gene encoding keratin 10 (KRT10); all result in frameshifts into the same alternative reading frame, producing an arginine-rich C-terminal peptide that redirects keratin 10 from the cytokeratin filament network to the nucleolus. The high frequency of somatic reversion in ichthyosis with confetti suggests that revertant stem cell clones are under strong positive selection and/or that the rate of mitotic recombination is elevated in individuals with this disorder.
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Affiliation(s)
- Keith A Choate
- Department of Dermatology, Yale University School of Medicine, New Haven, CT 06510, USA
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Almaani N, Nagy N, Liu L, Dopping-Hepenstal PJ, Lai-Cheong JE, Clements SE, Techanukul T, Tanaka A, Mellerio JE, McGrath JA. Revertant Mosaicism in Recessive Dystrophic Epidermolysis Bullosa. J Invest Dermatol 2010; 130:1937-40. [DOI: 10.1038/jid.2010.64] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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45
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Davis BR, Yan Q, Bui JH, Felix K, Moratto D, Muul LM, Prokopishyn NL, Blaese RM, Candotti F. Somatic mosaicism in the Wiskott–Aldrich syndrome: Molecular and functional characterization of genotypic revertants. Clin Immunol 2010; 135:72-83. [DOI: 10.1016/j.clim.2009.12.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 12/18/2009] [Accepted: 12/21/2009] [Indexed: 12/22/2022]
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46
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Ko MS, Marinkovich MP. Role of dermal-epidermal basement membrane zone in skin, cancer, and developmental disorders. Dermatol Clin 2010; 28:1-16. [PMID: 19945611 DOI: 10.1016/j.det.2009.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The dermal-epidermal basement membrane zone is an important epithelial and stromal interface, consisting of an intricately organized collection of intracellular, transmembrane, and extracellular matrix proteins. The basement membrane zone has several main functions including acting as a permeability barrier, forming an adhesive interface between epithelial cells and the underlying matrix, and controlling cellular organization and differentiation. This article identifies key molecular players of the dermal-epidermal membrane zone, and highlights recent research studies that have identified structural and functional roles of these components in the context of various blistering, neoplastic, and developmental syndromes.
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Affiliation(s)
- Myung S Ko
- Program in Epithelial Biology, Stanford University School of Medicine, 269 Campus Drive, Stanford, CA 94305, USA
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47
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Abstract
Collagen XVII has been identified as having a role in inherited junctional epidermolysis bullosa non-Herlitz (JEB-other, MIM #226650). The role of collagen XVII in both autoimmune and genetic blistering disorders demonstrates its relevance to dermal-epidermal adhesion. Collagen XVII is a major structural component of the hemidesmosome (HD), a highly specialized multiprotein complex that mediates the anchorage of basal epithelial cells to the underlying basement membrane in stratified, pseudostratified, and transitional epithelia. This article examines the genetic and pathological features of collagen XVII.
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Affiliation(s)
- Cristina Has
- Department of Dermatology, University Medical Center Freiburg, Hauptstr. 7, 79104 Freiburg, Germany.
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48
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Abstract
Up to 11% of patients affected with Wiskott-Aldrich syndrome (WAS) have presented with somatic mosaicism due to spontaneous in vivo reversion to normal of the original mutation or second-site compensatory mutations that restored production of the WAS gene product. The reasons underlying the high prevalence of this phenomenon in WAS are unclear and may include strong selective advantage of revertant cells over mutated populations, abnormally high general mutation rate and/or increased susceptibility of specific WAS gene sequences to DNA polymerase errors. Additional studies in human samples and in vitro/in vivo models of the disease will likely yield further insights into the mechanisms responsible for the occurrence of revertant mosaicism in WAS and elucidate additional biological characteristics of the WAS gene and protein.
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Affiliation(s)
- Brian R Davis
- Centre for Stem Cell Research, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, USA
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49
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Gostynski A, Deviaene F, Pasmooij A, Pas H, Jonkman M. Adhesive stripping to remove epidermis in junctional epidermolysis bullosa for revertant cell therapy. Br J Dermatol 2009; 161:444-7. [DOI: 10.1111/j.1365-2133.2009.09118.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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50
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