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Wen D, Hunjan M, Bardhan A, Harper N, Ogboli M, Ozoemena L, Liu L, Fine JD, Chapple I, Balacco DL, Heagerty A. Genotype-Phenotype Correlation in Junctional Epidermolysis Bullosa: Signposts to Severity. J Invest Dermatol 2024; 144:1334-1343.e14. [PMID: 38157931 DOI: 10.1016/j.jid.2023.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 10/10/2023] [Accepted: 11/09/2023] [Indexed: 01/03/2024]
Abstract
Junctional epidermolysis bullosa (JEB) is a rare autosomal recessive genodermatosis with a broad spectrum of phenotypes. Current genotype-phenotype paradigms are insufficient to accurately predict JEB subtype and characteristics from genotype, particularly for splice site variants, which account for over a fifth of disease-causing variants in JEB. This study evaluated the genetic and clinical findings from a JEB cohort, investigating genotype-phenotype correlations through bioinformatic analyses and comparison with previously reported variants. Eighteen unique variants in LAMB3, LAMA3, LAMC2, or COL17A1 were identified from 17 individuals. Seven had severe JEB, 9 had intermediate JEB, and 1 had laryngo-onycho-cutaneous syndrome. Seven variants were previously unreported. Deep phenotyping was completed for all intermediate JEB cases and demonstrated substantial variation between individuals. Splice site variants underwent analysis with SpliceAI, a state-of-the-art artificial intelligence tool, to predict resultant transcripts. Predicted functional effects included exon skipping and cryptic splice site activation, which provided potential explanations for disease severity and in most cases correlated with laminin-332 immunofluorescence. RT-PCR was performed for 1 case to investigate resultant transcripts produced from the splice site variant. This study expands the JEB genomic and phenotypic landscape. Artificial intelligence tools show potential for predicting the functional effects of splice site variants and may identify candidates for confirmatory laboratory investigation. Investigation of RNA transcripts will help to further elucidate genotype-phenotype correlations for novel variants.
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Affiliation(s)
- David Wen
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom; Adult Epidermolysis Bullosa Unit, Department of Dermatology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom; Oxford University Clinical Academic Graduate School, University of Oxford, Oxford, United Kingdom; Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom.
| | - Manrup Hunjan
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom; Adult Epidermolysis Bullosa Unit, Department of Dermatology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom; Department of Dermatology, Walsall Manor Hospital, Walsall, United Kingdom
| | - Ajoy Bardhan
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom; Adult Epidermolysis Bullosa Unit, Department of Dermatology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | - Natasha Harper
- Adult Epidermolysis Bullosa Unit, Department of Dermatology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | - Malobi Ogboli
- Paediatric Epidermolysis Bullosa Unit, Department of Paediatric Dermatology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, United Kingdom
| | - Linda Ozoemena
- National Diagnostic Epidermolysis Bullosa Laboratory, Synovis, St Thomas' Hospital, London, United Kingdom
| | - Lu Liu
- National Diagnostic Epidermolysis Bullosa Laboratory, Synovis, St Thomas' Hospital, London, United Kingdom
| | - Jo-David Fine
- Department of Dermatology, Vanderbilt University Medical Centre, Nashville, Tennessee, USA
| | - Iain Chapple
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom; Birmingham Dental Hospital, Birmingham Community Healthcare NHS Foundation Trust, Birmingham, United Kingdom; NIHR Birmingham Biomedical Research Centre Inflammation Research, Birmingham, United Kingdom
| | - Dario L Balacco
- Institute of Clinical Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Adrian Heagerty
- Adult Epidermolysis Bullosa Unit, Department of Dermatology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom; Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
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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] [What about the content of this article? (0)] [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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