1
|
Targeted NGS in Diagnostics of Genodermatosis Characterized by the Epidermolysis Bullosa Symptom Complex in 268 Russian Children. Int J Mol Sci 2022; 23:ijms232214343. [PMID: 36430820 PMCID: PMC9698894 DOI: 10.3390/ijms232214343] [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] [Received: 09/27/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
The pathogenic variants of genes encoding proteins, participating in the formation and functioning of epidermis and dermo-epidermal junctions, create a large variety of clinical phenotypes from: small localized to severe generalized dermatitis, as well as early, or even, prenatal death due to extensive epidermis loss. The diagnostic panel in this study was developed for the purposes of identifying these pathogenic genetic variants in 268 Russian children, who possessed the epidermolysis bullosa symptom complex in a selection of 247 families. This panel included the targeted areas of 33 genes, which are genetic variants that can lead to the development of the phenotype mentioned above. The usage of next generation sequencing allowed the revelation of 192 various altered alleles (of which 109 alleles were novel, i.e., had not been described previously). In addition, it allowed the definition of the genetic variants that are both typical for most of the examined children and for the separate ethnic groups inhabiting modern Russia. We found that the most characteristic mutations for the Dargin and Chechen ethnic groups are the c.3577del deletion in the COL7A1 gene and the c.2488G>A missense mutation in the COL17A1 gene, respectively. In addition, the study of haplotypes of microsatellite markers, which we managed to conduct in the Dargin population, confirmed the presence of the founder effect.
Collapse
|
2
|
Harvey N, Youssefian L, Saeidian AH, Vahidnezhad H, Uitto J. Pathomechanisms of epidermolysis bullosa: Beyond structural proteins. Matrix Biol 2022; 110:91-105. [DOI: 10.1016/j.matbio.2022.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/12/2022] [Accepted: 04/28/2022] [Indexed: 10/18/2022]
|
3
|
Slac2-b Coordinates Extracellular Vesicle Secretion to Regulate Keratinocyte Adhesion and Migration. J Invest Dermatol 2020; 141:523-532.e2. [PMID: 32890627 DOI: 10.1016/j.jid.2020.08.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 11/21/2022]
Abstract
Slac2-b, also known as exophilin-5, is a Rab27b effector protein with a role in exosome transport and is encoded by the EXPH5 gene. We previously described biallelic loss-of-function mutations in EXPH5 in an autosomal recessive form of epidermolysis bullosa simplex. However, how the loss of Slac2-b expression leads to skin fragility and erosions is unknown. In this study, we demonstrate that keratinocytes (KCs) isolated from two different individuals with mutations in EXPH5 have significant defects in cell‒matrix adhesion. EXPH5-mutant KCs also showed increased perinuclear accumulation and significantly reduced trafficking of CD63+ vesicles. These phenotypes were also seen in Slac2-b‒deficient KCs. This was coincident with a reduction in Rab27a protein expression in Slac2-b‒mutant KCs as well as reduced secretion of extracellular vesicles containing extracellular matrix proteins. Live imaging analysis revealed a strong correlation between CD63+ vesicle trafficking to the plasma membrane and focal adhesion dynamics. These findings support a role for Slac2-b in regulating local focal adhesion dynamics to support effective KC adhesion and provide insight into the underlying pathophysiology of inherited skin blistering.
Collapse
|
4
|
Diociaiuti A, Pisaneschi E, Rossi S, Condorelli AG, Carnevale C, Zambruno G, El Hachem M. Autosomal recessive epidermolysis bullosa simplex due to EXPH5 mutation: neonatal diagnosis of the first Italian case and literature review. J Eur Acad Dermatol Venereol 2020; 34:e694-e697. [PMID: 32176379 DOI: 10.1111/jdv.16372] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 03/02/2020] [Accepted: 03/10/2020] [Indexed: 11/27/2022]
Affiliation(s)
- A Diociaiuti
- Dermatology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - E Pisaneschi
- Medical Genetics Laboratory, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - S Rossi
- Pathology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - A G Condorelli
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - C Carnevale
- Dermatology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - G Zambruno
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - M El Hachem
- Dermatology Unit, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| |
Collapse
|
5
|
Lucky AW, Dagaonkar N, Lammers K, Husami A, Kissell D, Zhang K. A comprehensive next-generation sequencing assay for the diagnosis of epidermolysis bullosa. Pediatr Dermatol 2018; 35:188-197. [PMID: 29334134 DOI: 10.1111/pde.13392] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Historically, diagnosis of epidermolysis bullosa has required skin biopsies for electron microscopy, direct immunofluorescence to determine which gene(s) to choose for genetic testing, or both. METHODS To avoid these invasive tests, we developed a high-throughput next-generation sequencing (NGS)-based diagnostic assay called EBSEQ that allows simultaneous detection of mutations in 21 genes with known roles in epidermolysis bullosa pathogenicity. Mutations are confirmed with traditional Sanger sequencing. RESULTS We present our EBSEQ assay and preliminary studies on the first 43 subjects tested. We identified 11 cases of epidermolysis bullosa simplex, five cases of junctional epidermolysis bullosa, 11 cases of dominant dystrophic epidermolysis bullosa, 15 cases of recessive dystrophic epidermolysis bullosa, and one case that remains without diagnosis. We also found an additional 52 variants of uncertain clinical significance in 17 of the 21 epidermolysis bullosa-associated genes tested. Three of the variants of uncertain clinical significance were also found in three other patients, for a total of 49 unique variants of uncertain clinical significance. We found the clinical sensitivity of the assay to be 75% to 98% and the analytical sensitivity to be 99% in identifying base substitutions and small deletions and duplications. Turnaround time was 3 to 6 weeks. CONCLUSIONS EBSEQ is a sensitive, relatively rapid, minimally invasive, comprehensive genetic assay for the diagnosis of epidermolysis bullosa.
Collapse
Affiliation(s)
- Anne W Lucky
- Division of General and Community Pediatrics and Cincinnati Children's Epidermolysis Bullosa Center, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Neha Dagaonkar
- Division of Human Genetics, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Karen Lammers
- Division of General and Community Pediatrics and Cincinnati Children's Epidermolysis Bullosa Center, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Ammar Husami
- Division of Human Genetics, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Diane Kissell
- Division of Human Genetics, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Kejian Zhang
- Division of Human Genetics, Cincinnati Children's Hospital, Cincinnati, OH, USA
| |
Collapse
|
6
|
Malchin N, Sarig O, Grafi-Cohen M, Geller S, Goldberg I, Shani A, Gat A, Sprecher E, Mashiah J. A novel homozygous deletion in EXPH5 causes a skin fragility phenotype. Clin Exp Dermatol 2016; 41:915-918. [PMID: 27730671 DOI: 10.1111/ced.12908] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2015] [Indexed: 11/26/2022]
Abstract
Epidermolysis bullosa simplex (EBS) is the most common form of EB. Eight different genes have been implicated in the pathogenesis of different types of EBS, but a substantial portion of the cases cannot be attributed to mutations in known genes. Recently, recessive mutations in the gene EXPH5 (encoding exophilin-5, also known as Slac2-b) were identified in patients affected with a mild form of EBS. We used immunohistochemistry, Sanger sequencing and PCR-restriction fragment length polymorphism analysis to identify the cause of mild congenital skin fragility in a 3-year-old girl. No mutations were detected in KRT5 or KRT14, but we identified a novel homozygous deletion in EXPH5, which was found to cosegregate with the disease phenotype in the family. Our results further expand the spectrum of mutations in EXPH5. Appraisal of the present case against previously reported patients indicate that EXPH5 mutations result in a distinctive skin fragility phenotype, with minimal blistering compared with other forms of basal EBS.
Collapse
Affiliation(s)
- N Malchin
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - O Sarig
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - M Grafi-Cohen
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - S Geller
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - I Goldberg
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - A Shani
- Department of Dermatology, Ha Emek Medical Center, Afula, Israel
| | - A Gat
- Department of Pathology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - E Sprecher
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Pediatric Dermatology Unit, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - J Mashiah
- Department of Dermatology, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Pediatric Dermatology Unit, Dana Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| |
Collapse
|
7
|
McGrath JA. Recently Identified Forms of Epidermolysis Bullosa. Ann Dermatol 2015; 27:658-66. [PMID: 26719633 PMCID: PMC4695416 DOI: 10.5021/ad.2015.27.6.658] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/04/2015] [Accepted: 09/07/2015] [Indexed: 12/03/2022] Open
Abstract
Epidermolysis bullosa (EB) comprises a collection of clinically diverse inherited blistering diseases that affect the skin and, in some subtypes, mucous membranes and other organs. Currently classified into four main subtypes (EB simplex, junctional EB, dystrophic EB, and Kindler syndrome, mainly based on the level of skin cleavage), the spectrum of EB extends to more than 30 clinical subtypes with pathogenic mutations in at least 18 distinct genes. This review focuses on three recent additions to variants of EB: all are autosomal recessive, and result from mutations in either DST-e (coding for epidermal dystonin, also known as the 230 kDa bullous pemphigoid antigen, BP230), EXPH5 (coding for exophilin-5, also known as Slac2-b), or ITGA3 (coding for the integrin alpha-3 subunit). Each of these new forms of EB is reviewed with respect to the initial gene discovery, clinical features, the current mutation database, and skin pathology. Awareness of these recently described forms of EB is helpful in the clinical evaluation of patients with EB and in defining genotype-phenotype correlation for inherited blistering skin diseases.
Collapse
Affiliation(s)
- John A McGrath
- St John's Institute of Dermatology, King's College London (Guy's Campus), London, UK
| |
Collapse
|
8
|
Rashidghamat E, Ozoemena L, Liu L, McGrath JA, Martinez AE, Mellerio JE. Mutations in EXPH5 underlie a rare subtype of autosomal recessive epidermolysis bullosa simplex. Br J Dermatol 2015. [PMID: 26211931 DOI: 10.1111/bjd.14047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- E Rashidghamat
- St John's Institute of Dermatology, King's College London, London, U.K
| | - L Ozoemena
- Viapath, St Thomas' Hospital, London, U.K
| | - L Liu
- Viapath, St Thomas' Hospital, London, U.K
| | - J A McGrath
- St John's Institute of Dermatology, King's College London, London, U.K
| | - A E Martinez
- Department of Dermatology, Great Ormond Street for Children NHS Foundation Trust, London, U.K
| | - J E Mellerio
- St John's Institute of Dermatology, King's College London, London, U.K.,Department of Dermatology, Great Ormond Street for Children NHS Foundation Trust, London, U.K
| |
Collapse
|
9
|
Homberg M, Ramms L, Schwarz N, Dreissen G, Leube RE, Merkel R, Hoffmann B, Magin TM. Distinct Impact of Two Keratin Mutations Causing Epidermolysis Bullosa Simplex on Keratinocyte Adhesion and Stiffness. J Invest Dermatol 2015; 135:2437-2445. [DOI: 10.1038/jid.2015.184] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/10/2015] [Accepted: 04/25/2015] [Indexed: 12/20/2022]
|