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Giardina E, Camaño P, Burton-Jones S, Ravenscroft G, Henning F, Magdinier F, van der Stoep N, van der Vliet PJ, Bernard R, Tomaselli PJ, Davis MR, Nishino I, Oflazer P, Race V, Vishnu VY, Williams V, Sobreira CFR, van der Maarel SM, Moore SA, Voermans NC, Lemmers RJLF. Best practice guidelines on genetic diagnostics of facioscapulohumeral muscular dystrophy: Update of the 2012 guidelines. Clin Genet 2024; 106:13-26. [PMID: 38685133 PMCID: PMC11147721 DOI: 10.1111/cge.14533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 03/26/2024] [Accepted: 04/02/2024] [Indexed: 05/02/2024]
Abstract
The gold standard for facioscapulohumeral muscular dystrophy (FSHD) genetic diagnostic procedures was published in 2012. With the increasing complexity of the genetics of FSHD1 and 2, the increase of genetic testing centers, and the start of clinical trials for FSHD, it is crucial to provide an update on our knowledge of the genetic features of the FSHD loci and renew the international consensus on the molecular testing recommendations. To this end, members of the FSHD European Trial Network summarized the evidence presented during the 2022 ENMC meeting on Genetic diagnosis, clinical outcome measures, and biomarkers. The working group additionally invited genetic and clinical experts from the USA, India, Japan, Australia, South-Africa, and Brazil to provide a global perspective. Six virtual meetings were organized to reach consensus on the minimal requirements for genetic confirmation of FSHD1 and FSHD2. Here, we present the clinical and genetic features of FSHD, specific features of FSHD1 and FSHD2, pros and cons of established and new technologies (Southern blot in combination with either linear or pulsed-field gel electrophoresis, molecular combing, optical genome mapping, FSHD2 methylation analysis and FSHD2 genotyping), the possibilities and challenges of prenatal testing, including pre-implantation genetic testing, and the minimal requirements and recommendations for genetic confirmation of FSHD1 and FSHD2. This consensus is expected to contribute to current clinical management and trial-readiness for FSHD.
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Affiliation(s)
- Emiliano Giardina
- Genomic Medicine Laboratory UILDM, IRCCS Fondazione Santa Lucia, Rome, Italy
- Department of Biomedicine & Prevention, Tor Vergata University of Rome, Rome, Italy
| | - Pilar Camaño
- Molecular Diagnostics Platform, Biogipuzkoa Health Research Institute, Hospital Universitario Donostia, San Sebastián, Spain
- CIBERNED, CIBER, Spanish Ministry of Science & Innovation, Carlos III Health Institute, Madrid, Spain
| | | | - Gina Ravenscroft
- Harry Perkins Institute of Medical Research, University of Western Australia, Nedlands, Western Australia, Australia
| | - Franclo Henning
- Division of Neurology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | | | - Nienke van der Stoep
- Department of Clinical Genetics, Leiden University Medical Center, The Netherlands
| | | | - Rafaëlle Bernard
- Aix Marseille Univ, INSERM, Marseille Medical Genetics, Marseille, France
- Centre Hospitalier Universitaire Timone Adultes, Biogénopôle, Service de Génétique Médicale, Marseille, France
| | - Pedro J Tomaselli
- Department of Neurosciences, Division of Neurology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Mark R Davis
- Department of Diagnostic Genomics, PathWest Laboratory Medicine, Perth, Western Australia, Australia
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
- Department of Genome Medicine Development, Clinical Genome Analysis, Medical Genome Center (MGC), National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
| | - Piraye Oflazer
- Department of Neurology, Koç University Hospital Muscle Center, Koç University Medical Faculty, Istanbul, Turkey
| | - Valerie Race
- Clinical Laboratory Geneticist, Human Genetics, UZ Leuven, Leuven, Belgium
| | - Venugopalan Y Vishnu
- Department of Neurology, All India Institute of Medical Sciences (AIIMS), Delhi, India
| | | | - Cláudia F R Sobreira
- Department of Neurosciences, Division of Neurology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | | | - Steve A Moore
- Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Department of Pathology, Roy J. And Lucille A. Carver College of Medicine, The University of Iowa, Iowa City, Iowa, USA
| | - Nicol C Voermans
- Department of Neurology, Radboud university medical center, Nijmegen, The Netherlands
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Yang JL, Gu H, Yuan ZZ, Xie XH, Yang YF, Tan ZP. Identification of a pathogenic SMCHD1 variant in a Chinese patient with bosma arhinia microphthalmia syndrome: a case report. BMC Med Genomics 2024; 17:136. [PMID: 38773541 PMCID: PMC11110391 DOI: 10.1186/s12920-024-01907-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 05/13/2024] [Indexed: 05/24/2024] Open
Abstract
BACKGROUND Bosma arhinia microphthalmia syndrome (BAMS; MIM603457) is a rare genetic disorder, predominantly autosomal dominant. It is a multi-system developmental disorder characterized by severe hypoplasia of the nose and eyes, and reproductive system defects. BAMS is extremely rare in the world and no cases have been reported in Chinese population so far. Pathogenic variants in the SMCHD1 gene (MIM614982) cause BAMS, while the underlying molecular mechanisms requires further investigation. CASE PRESENTATION In this study, a Chinese girl who has suffered from congenital absence of nose and microphthalmia was enrolled and subsequently submitted to a comprehensive clinical and genetic evaluation. Whole-exome sequencing (WES) was employed to identify the genetic entity of thisgirl. A heterozygous pathogenic variant, NM_015295, c.1025G > C; p. (Trp342Ser) of SMCHD1 was identified. By performing very detailed physical and genetic examinations, the patient was diagnosed as BAMS. CONCLUSION This report is the first description of a variant in SMCHD1 in a Chinese patient affected with BAMS.Our study not only furnished valuable genetic data for counseling of BAMS, but also confirmed the diagnosis of BAMS, which may help the management and prognosis for this patient.
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Affiliation(s)
- Jun-Lin Yang
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Heng Gu
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Zhuang-Zhuang Yuan
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China
| | - Xiao-Hui Xie
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Yi-Feng Yang
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China
| | - Zhi-Ping Tan
- Department of Cardiovascular Surgery, the Second Xiangya Hospital of Central South University, Changsha, China.
- Clinical Center for Gene Diagnosis and Therapy, Department of Cardiovascular Surgery, The Second Xiangya Hospital of Central South University, Changsha, Hunan, 410011, China.
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Atencia Goñi J, Orera Clemente M, Del Valle Diéguez MJ, González Fernández L, González Albarrán O. Clinical report of Bosma arhinia microphthalmia syndrome with a new variant on SMCHD1 gene. A case report. ENDOCRINOL DIAB NUTR 2024; 71:138-143. [PMID: 38555111 DOI: 10.1016/j.endien.2024.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 12/29/2023] [Indexed: 04/02/2024]
Abstract
The Bosma syndrome (BAMS: Bosma arhinia microphthalmia syndrome) is a condition first described in 1972. Since then, several reviews have published the cases looking for diagnostic criteria and associated genetic alterations. The mutation in the SMCHD1 gene (Structural Maintenance of Chromosomes flexible Hinge Domain containing protein 1) seems to explain a part of the development of the phenotype. Not all cases show the same alterations or meet the classic diagnostic criteria, and few have undergone genetic analysis. We present a case with a new variant in this gene and an update of the literature on this syndrome with the aim of improving the diagnosis and follow-up of these patients.
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Affiliation(s)
- José Atencia Goñi
- Department of Endocrinology and Nutrition, HGU Gregorio Marañón, Madrid, Spain.
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Tapia Del Fierro A, den Hamer B, Benetti N, Jansz N, Chen K, Beck T, Vanyai H, Gurzau AD, Daxinger L, Xue S, Ly TTN, Wanigasuriya I, Iminitoff M, Breslin K, Oey H, Krom YD, van der Hoorn D, Bouwman LF, Johanson TM, Ritchie ME, Gouil QA, Reversade B, Prin F, Mohun T, van der Maarel SM, McGlinn E, Murphy JM, Keniry A, de Greef JC, Blewitt ME. SMCHD1 has separable roles in chromatin architecture and gene silencing that could be targeted in disease. Nat Commun 2023; 14:5466. [PMID: 37749075 PMCID: PMC10519958 DOI: 10.1038/s41467-023-40992-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 08/07/2023] [Indexed: 09/27/2023] Open
Abstract
The interplay between 3D chromatin architecture and gene silencing is incompletely understood. Here, we report a novel point mutation in the non-canonical SMC protein SMCHD1 that enhances its silencing capacity at endogenous developmental targets. Moreover, it also results in enhanced silencing at the facioscapulohumeral muscular dystrophy associated macrosatellite-array, D4Z4, resulting in enhanced repression of DUX4 encoded by this repeat. Heightened SMCHD1 silencing perturbs developmental Hox gene activation, causing a homeotic transformation in mice. Paradoxically, the mutant SMCHD1 appears to enhance insulation against other epigenetic regulators, including PRC2 and CTCF, while depleting long range chromatin interactions akin to what is observed in the absence of SMCHD1. These data suggest that SMCHD1's role in long range chromatin interactions is not directly linked to gene silencing or insulating the chromatin, refining the model for how the different levels of SMCHD1-mediated chromatin regulation interact to bring about gene silencing in normal development and disease.
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Affiliation(s)
- Andres Tapia Del Fierro
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Bianca den Hamer
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Natalia Benetti
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Natasha Jansz
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Kelan Chen
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Tamara Beck
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Hannah Vanyai
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | - Alexandra D Gurzau
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Lucia Daxinger
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - Shifeng Xue
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Thanh Thao Nguyen Ly
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Iromi Wanigasuriya
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Megan Iminitoff
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Kelsey Breslin
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
| | - Harald Oey
- Queensland Institute of Medical Research, Brisbane, QLD, Australia
| | - Yvonne D Krom
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Dinja van der Hoorn
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Linde F Bouwman
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Timothy M Johanson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Matthew E Ritchie
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Quentin A Gouil
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Bruno Reversade
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
- Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Fabrice Prin
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | - Timothy Mohun
- Crick Advanced Light Microscopy Facility, The Francis Crick Institute, London, UK
| | | | - Edwina McGlinn
- EMBL Australia, Monash University, Clayton, VIC, Australia
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | - James M Murphy
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Andrew Keniry
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
| | - Marnie E Blewitt
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC, Australia.
- The Department of Medical Biology, University of Melbourne, Melbourne, VIC, Australia.
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5
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Strafella C, Caputo V, Bortolani S, Torchia E, Megalizzi D, Trastulli G, Monforte M, Colantoni L, Caltagirone C, Ricci E, Tasca G, Cascella R, Giardina E. Whole exome sequencing highlights rare variants in CTCF, DNMT1, DNMT3A, EZH2 and SUV39H1 as associated with FSHD. Front Genet 2023; 14:1235589. [PMID: 37674478 PMCID: PMC10477786 DOI: 10.3389/fgene.2023.1235589] [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: 06/06/2023] [Accepted: 08/09/2023] [Indexed: 09/08/2023] Open
Abstract
Introduction: Despite the progress made in the study of Facioscapulohumeral Dystrophy (FSHD), the wide heterogeneity of disease complicates its diagnosis and the genotype-phenotype correlation among patients and within families. In this context, the present work employed Whole Exome Sequencing (WES) to investigate known and unknown genetic contributors that may be involved in FSHD and may represent potential disease modifiers, even in presence of a D4Z4 Reduced Allele (DRA). Methods: A cohort of 126 patients with clinical signs of FSHD were included in the study, which were characterized by D4Z4 sizing, methylation analysis and WES. Specific protocols were employed for D4Z4 sizing and methylation analysis, whereas the Illumina® Next-Seq 550 system was utilized for WES. The study included both patients with a DRA compatible with FSHD diagnosis and patients with longer D4Z4 alleles. In case of patients harboring relevant variants from WES, the molecular analysis was extended to the family members. Results: The WES data analysis highlighted 20 relevant variants, among which 14 were located in known genetic modifiers (SMCHD1, DNMT3B and LRIF1) and 6 in candidate genes (CTCF, DNMT1, DNMT3A, EZH2 and SUV39H1). Most of them were found together with a permissive short (4-7 RU) or borderline/long DRA (8-20 RU), supporting the possibility that different genes can contribute to disease heterogeneity in presence of a FSHD permissive background. The segregation and methylation analysis among family members, together with clinical findings, provided a more comprehensive picture of patients. Discussion: Our results support FSHD pathomechanism being complex with a multigenic contribution by several known (SMCHD1, DNMT3B, LRIF1) and possibly other candidate genes (CTCF, DNMT1, DNMT3A, EZH2, SUV39H1) to disease penetrance and expressivity. Our results further emphasize the importance of extending the analysis of molecular findings within the proband's family, with the purpose of providing a broader framework for understanding single cases and allowing finer genotype-phenotype correlations in FSHD-affected families.
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Affiliation(s)
- Claudia Strafella
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Valerio Caputo
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Sara Bortolani
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Eleonora Torchia
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Domenica Megalizzi
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Giulia Trastulli
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Mauro Monforte
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
| | - Luca Colantoni
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Carlo Caltagirone
- Department of Clinical and Behavioral Neurology, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Enzo Ricci
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- Istituto di Neurologia, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Giorgio Tasca
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy
- John Walton Muscular Dystrophy Research Centre, Newcastle University and Newcastle Hospitals NHS Foundation Trusts, Newcastle UponTyne, United Kingdom
| | - Raffaella Cascella
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
- Department of Biomedical Sciences, Catholic University Our Lady of Good Counsel, Tirana, Albania
| | - Emiliano Giardina
- Genomic Medicine Laboratory UILDM, IRCCS Santa Lucia Foundation, Rome, Italy
- Medical Genetics Laboratory, Department of Biomedicine and Prevention, Tor Vergata University, Rome, Italy
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6
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Inoue K, Bostan H, Browne MR, Bevis OF, Bortner CD, Moore SA, Stence AA, Martin NP, Chen SH, Burkholder AB, Li JL, Shaw ND. DUX4 double whammy: The transcription factor that causes a rare muscular dystrophy also kills the precursors of the human nose. SCIENCE ADVANCES 2023; 9:eabq7744. [PMID: 36800423 PMCID: PMC9937577 DOI: 10.1126/sciadv.abq7744] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 01/12/2023] [Indexed: 05/19/2023]
Abstract
SMCHD1 mutations cause congenital arhinia (absent nose) and a muscular dystrophy called FSHD2. In FSHD2, loss of SMCHD1 repressive activity causes expression of double homeobox 4 (DUX4) in muscle tissue, where it is toxic. Studies of arhinia patients suggest a primary defect in nasal placode cells (human nose progenitors). Here, we show that upon SMCHD1 ablation, DUX4 becomes derepressed in H9 human embryonic stem cells (hESCs) as they differentiate toward a placode cell fate, triggering cell death. Arhinia and FSHD2 patient-derived induced pluripotent stem cells (iPSCs) express DUX4 when converted to placode cells and demonstrate variable degrees of cell death, suggesting an environmental disease modifier. HSV-1 may be one such modifier as herpesvirus infection amplifies DUX4 expression in SMCHD1 KO hESC and patient iPSC. These studies suggest that arhinia, like FSHD2, is due to compromised SMCHD1 repressive activity in a cell-specific context and provide evidence for an environmental modifier.
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Affiliation(s)
- Kaoru Inoue
- Pediatric Neuroendocrinology Group, Clinical Research Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, USA
| | - Hamed Bostan
- Integrative Bioinformatics, NIEHS, Research Triangle Park, NC, USA
| | - MaKenna R. Browne
- Pediatric Neuroendocrinology Group, Clinical Research Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, USA
| | - Owen F. Bevis
- Pediatric Neuroendocrinology Group, Clinical Research Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, USA
| | - Carl D. Bortner
- Signal Transduction Laboratory, NIEHS, Research Triangle Park, NC, USA
| | - Steven A. Moore
- Department of Pathology, University of Iowa Carver College of Medicine and Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, Iowa City, IA, USA
| | - Aaron A. Stence
- University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | | | - Shih-Heng Chen
- Viral Vector Core, NIEHS, Research Triangle Park, NC, USA
| | | | - Jian-Liang Li
- Integrative Bioinformatics, NIEHS, Research Triangle Park, NC, USA
| | - Natalie D. Shaw
- Pediatric Neuroendocrinology Group, Clinical Research Branch, National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, USA
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7
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Tihaya MS, Mul K, Balog J, de Greef JC, Tapscott SJ, Tawil R, Statland JM, van der Maarel SM. Facioscapulohumeral muscular dystrophy: the road to targeted therapies. Nat Rev Neurol 2023; 19:91-108. [PMID: 36627512 DOI: 10.1038/s41582-022-00762-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2022] [Indexed: 01/11/2023]
Abstract
Advances in the molecular understanding of facioscapulohumeral muscular dystrophy (FSHD) have revealed that FSHD results from epigenetic de-repression of the DUX4 gene in skeletal muscle, which encodes a transcription factor that is active in early embryonic development but is normally silenced in almost all somatic tissues. These advances also led to the identification of targets for disease-altering therapies for FSHD, as well as an improved understanding of the molecular mechanism of the disease and factors that influence its progression. Together, these developments led the FSHD research community to shift its focus towards the development of disease-modifying treatments for FSHD. This Review presents advances in the molecular and clinical understanding of FSHD, discusses the potential targeted therapies that are currently being explored, some of which are already in clinical trials, and describes progress in the development of FSHD-specific outcome measures and assessment tools for use in future clinical trials.
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Affiliation(s)
- Mara S Tihaya
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Karlien Mul
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Judit Balog
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stephen J Tapscott
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, USA
| | - Jeffrey M Statland
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA
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8
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Mariot V, Dumonceaux J. Gene Editing to Tackle Facioscapulohumeral Muscular Dystrophy. Front Genome Ed 2022; 4:937879. [PMID: 35910413 PMCID: PMC9334676 DOI: 10.3389/fgeed.2022.937879] [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: 05/06/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Facioscapulohumeral dystrophy (FSHD) is a skeletal muscle disease caused by the aberrant expression of the DUX4 gene in the muscle tissue. To date, different therapeutic approaches have been proposed, targeting DUX4 at the DNA, RNA or protein levels. The recent development of the clustered regularly interspaced short-palindromic repeat (CRISPR) based technology opened new avenues of research, and FSHD is no exception. For the first time, a cure for genetic muscular diseases can be considered. Here, we describe CRISPR-based strategies that are currently being investigated for FSHD. The different approaches include the epigenome editing targeting the DUX4 gene and its promoter, gene editing targeting the polyadenylation of DUX4 using TALEN, CRISPR/cas9 or adenine base editing and the CRISPR-Cas9 genome editing for SMCHD1. We also discuss challenges facing the development of these gene editing based therapeutics.
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Affiliation(s)
- Virginie Mariot
- NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health and Great Ormond Street Hospital NHS Trust, University College London, London, United Kingdom
| | - Julie Dumonceaux
- NIHR Biomedical Research Centre, Great Ormond Street Institute of Child Health and Great Ormond Street Hospital NHS Trust, University College London, London, United Kingdom
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9
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Epigenetic modifier SMCHD1 maintains a normal pool of long-term hematopoietic stem cells. iScience 2022; 25:104684. [PMID: 35856023 PMCID: PMC9287190 DOI: 10.1016/j.isci.2022.104684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 05/16/2022] [Accepted: 06/24/2022] [Indexed: 11/30/2022] Open
Abstract
SMCHD1 (structural maintenance of chromosomes hinge domain containing 1) is a noncanonical SMC protein that mediates long-range repressive chromatin structures. SMCHD1 is required for X chromosome inactivation in female cells and repression of imprinted and clustered autosomal genes, with SMCHD1 mutations linked to human diseases facioscapulohumeral muscular dystrophy (FSHD) and bosma arhinia and micropthalmia syndrome (BAMS). We used a conditional mouse model to investigate SMCHD1 in hematopoiesis. Smchd1-deleted mice maintained steady-state hematopoiesis despite showing an impaired reconstitution capacity in competitive bone marrow transplantations and age-related hematopoietic stem cell (HSC) loss. This phenotype was more pronounced in Smchd1-deleted females, which showed a loss of quiescent HSCs and fewer B cells. Gene expression profiling of Smchd1-deficient HSCs and B cells revealed known and cell-type-specific SMCHD1-sensitive genes and significant disruption to X-linked gene expression in female cells. These data show SMCHD1 is a regulator of HSCs whose effects are more profound in females. SMCHD1 is not required to maintain steady-state hematopoiesis Smchd1-deletion leads to loss of adult hematopoietic stem cells Smchd1-deleted female mice are more severely affected than males SMCHD1 maintains cellular quiescence in female hematopoietic stem cells
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10
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Goossens R, Tihaya MS, van den Heuvel A, Tabot-Ndip K, Willemsen IM, Tapscott SJ, González-Prieto R, Chang JG, Vertegaal ACO, Balog J, van der Maarel SM. A proteomics study identifying interactors of the FSHD2 gene product SMCHD1 reveals RUVBL1-dependent DUX4 repression. Sci Rep 2021; 11:23642. [PMID: 34880314 PMCID: PMC8654949 DOI: 10.1038/s41598-021-03030-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 11/23/2021] [Indexed: 11/25/2022] Open
Abstract
Structural Maintenance of Chromosomes Hinge Domain Containing 1 (SMCHD1) is a chromatin repressor, which is mutated in > 95% of Facioscapulohumeral dystrophy (FSHD) type 2 cases. In FSHD2, SMCHD1 mutations ultimately result in the presence of the cleavage stage transcription factor DUX4 in muscle cells due to a failure in epigenetic repression of the D4Z4 macrosatellite repeat on chromosome 4q, which contains the DUX4 locus. While binding of SMCHD1 to D4Z4 and its necessity to maintain a repressive D4Z4 chromatin structure in somatic cells are well documented, it is unclear how SMCHD1 is recruited to D4Z4, and how it exerts its repressive properties on chromatin. Here, we employ a quantitative proteomics approach to identify and characterize novel SMCHD1 interacting proteins, and assess their functionality in D4Z4 repression. We identify 28 robust SMCHD1 nuclear interactors, of which 12 are present in D4Z4 chromatin of myocytes. We demonstrate that loss of one of these SMCHD1 interacting proteins, RuvB-like 1 (RUVBL1), further derepresses DUX4 in FSHD myocytes. We also confirm the interaction of SMCHD1 with EZH inhibitory protein (EZHIP), a protein which prevents global H3K27me3 deposition by the Polycomb repressive complex PRC2, providing novel insights into the potential function of SMCHD1 in the repression of DUX4 in the early stages of embryogenesis. The SMCHD1 interactome outlined herein can thus provide further direction into research on the potential function of SMCHD1 at genomic loci where SMCHD1 is known to act, such as D4Z4 repeats, the inactive X chromosome, autosomal gene clusters, imprinted loci and telomeres.
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Affiliation(s)
- Remko Goossens
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Mara S Tihaya
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Anita van den Heuvel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Klorane Tabot-Ndip
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Iris M Willemsen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stephen J Tapscott
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, USA
| | - Román González-Prieto
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jer-Gung Chang
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Alfred C O Vertegaal
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Judit Balog
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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Jia FF, Drew AP, Nicholson GA, Corbett A, Kumar KR. Facioscapulohumeral muscular dystrophy type 2: an update on the clinical, genetic, and molecular findings. Neuromuscul Disord 2021; 31:1101-1112. [PMID: 34711481 DOI: 10.1016/j.nmd.2021.09.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 09/01/2021] [Accepted: 09/09/2021] [Indexed: 11/25/2022]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is a common genetic disease of the skeletal muscle with a characteristic pattern of weakness. Facioscapulohumeral muscular dystrophy type 2 (FSHD2) accounts for approximately 5% of all cases of FSHD and describes patients without a D4Z4 repeat contraction on chromosome 4. Phenotypically FSHD2 shows virtually no difference from FSHD1 and both forms of FSHD arise via a common downstream mechanism of epigenetic derepression of the transcription factor DUX4 in skeletal muscle cells. This results in expression of DUX4 and target genes leading to skeletal muscle toxicity. Over the past decade, major progress has been made in our understanding of the genetic and epigenetic architecture that underlies FSHD2 pathogenesis, as well as the clinical manifestations and disease progression. These include the finding that FSHD2 is a digenic disease and that mutations in the genes SMCHD1, DNMT3B, and more recently LRIF1, can cause FSHD2. FSHD2 is complex and it is important that clinicians keep abreast of recent developments; this review aims to serve as an update of the clinical, genetic, and molecular research into this condition.
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Affiliation(s)
- Fangzhi Frank Jia
- Department of Neurology, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia.
| | - Alexander P Drew
- Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia.
| | - Garth Alexander Nicholson
- Department of Neurology, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia; Molecular Medicine Laboratory, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia; Northcott Neuroscience Laboratory, ANZAC Research Institute, Concord, New South Wales 2139, Australia; Sydney Medical School, University of Sydney, Camperdown, New South Wales 2050, Australia.
| | - Alastair Corbett
- Department of Neurology, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia; Sydney Medical School, University of Sydney, Camperdown, New South Wales 2050, Australia.
| | - Kishore Raj Kumar
- Department of Neurology, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia; Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia; Molecular Medicine Laboratory, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia; Sydney Medical School, University of Sydney, Camperdown, New South Wales 2050, Australia.
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12
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Lemmers RJLF, Vliet PJ, Granado DSL, Stoep N, Buermans H, Schendel R, Schimmel J, Visser M, Coster R, Jeanpierre M, Laforet P, Upadhyaya M, Engelen B, Sacconi S, Tawil R, Voermans NC, Rogers M, van der Maarel SM. High resolution breakpoint junction mapping of proximally extended D4Z4 deletions in FSHD1 reveals evidence for a founder effect. Hum Mol Genet 2021; 31:748-760. [PMID: 34559225 DOI: 10.1093/hmg/ddab250] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 08/17/2021] [Accepted: 08/24/2021] [Indexed: 01/09/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is an inherited myopathy clinically characterized by weakness in the facial, shoulder girdle and upper arm muscles. FSHD is caused by chromatin relaxation of the D4Z4 macrosatellite repeat, mostly by a repeat contraction, facilitating ectopic expression of DUX4 in skeletal muscle. Genetic diagnosis for FSHD is generally based on the sizing and haplotyping of the D4Z4 repeat on chromosome 4 by Southern blotting, molecular combing or single-molecule optical mapping, which is usually straight forward but can be complicated by atypical rearrangements of the D4Z4 repeat. One of these rearrangements is a D4Z4 proximally-extended deletion (DPED) allele, where not only the D4Z4 repeat is partially deleted, but also sequences immediately proximal to the repeat are lost, which can impede accurate diagnosis in all genetic methods. Previously, we identified several DPED alleles in FSHD and estimated the size of the proximal deletions by a complex pulsed-field gel electrophoresis and Southern blot strategy. Here, using next generation sequencing, we have defined the breakpoint junctions of these DPED alleles at the base pair resolution in 12 FSHD families and 4 control individuals facilitating a PCR-based diagnosis of these DPED alleles. Our results show that half of the DPED alleles are derivates of an ancient founder allele. For some DPED alleles we found that genetic elements are deleted such as DUX4c, FRG2, DBE-T and myogenic enhancers necessitating re-evaluation of their role in FSHD pathogenesis.
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Affiliation(s)
- Richard J L F Lemmers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Patrick J Vliet
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Nienke Stoep
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Henk Buermans
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Robin Schendel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Joost Schimmel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Marianne Visser
- Academic Medical Center, Department of Neurology, Amsterdam, The Netherlands
| | - Rudy Coster
- Department of Pediatrics, Division of Pediatric Neurology, Ghent University Hospital, Ghent, Belgium
| | | | - Pascal Laforet
- Nord-Est/Ile-de-France Neuromuscular Reference Center, FHU PHENIX, Neurology Department, Raymond-Poincaré Hospital, Versailles Saint-Quentin-en-Yvelines - Paris Saclay University, Garches, France
| | - Meena Upadhyaya
- Department of Medical Genetics, Cardiff University, Cardif, UK
| | - Baziel Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, The Netherlands
| | - Sabrina Sacconi
- Centre de référence des Maladies neuromusculaires, Nice University Hospital, Nice, France
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, USA
| | - Nicol C Voermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, The Netherlands
| | - Mark Rogers
- Department of Medical Genetics, Cardiff University, Cardif, UK
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Precise Epigenetic Analysis Using Targeted Bisulfite Genomic Sequencing Distinguishes FSHD1, FSHD2, and Healthy Subjects. Diagnostics (Basel) 2021; 11:diagnostics11081469. [PMID: 34441403 PMCID: PMC8393475 DOI: 10.3390/diagnostics11081469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/01/2021] [Accepted: 08/11/2021] [Indexed: 12/16/2022] Open
Abstract
The true prevalence of facioscapulohumeral muscular dystrophy (FSHD) is unknown due to difficulties with accurate clinical evaluation and the complexities of current genetic diagnostics. Interestingly, all forms of FSHD are linked to epigenetic changes in the chromosome 4q35 D4Z4 macrosatellite, suggesting that epigenetic analysis could provide an avenue for sequence-based FSHD diagnostics. However, studies assessing DNA methylation at the FSHD locus have produced conflicting results; thus, the utility of this technique as an FSHD diagnostic remains controversial. Here, we critically compared two protocols for epigenetic analysis of the FSHD region using bisulfite genomic sequencing: Jones et al., that contends to be individually diagnostic for FSHD1 and FSHD2, and Gaillard et al., that can identify some changes in DNA methylation levels between groups of clinically affected FSHD and healthy subjects, but is not individually diagnostic for any form of FSHD. We performed both sets of assays on the same genetically confirmed samples and showed that this discrepancy was due strictly to differences in amplicon specificity. We propose that the epigenetic status of the FSHD-associated D4Z4 arrays, when accurately assessed, is a diagnostic for genetic FSHD and can readily distinguish between healthy, FSHD1 and FSHD2. Thus, epigenetic diagnosis of FSHD, which can be performed on saliva DNA, will greatly increase accessibility to FSHD diagnostics for populations around the world.
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Banerji CRS, Zammit PS. Pathomechanisms and biomarkers in facioscapulohumeral muscular dystrophy: roles of DUX4 and PAX7. EMBO Mol Med 2021; 13:e13695. [PMID: 34151531 PMCID: PMC8350899 DOI: 10.15252/emmm.202013695] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 03/27/2021] [Accepted: 03/30/2021] [Indexed: 12/29/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is characterised by progressive skeletal muscle weakness and wasting. FSHD is linked to epigenetic derepression of the subtelomeric D4Z4 macrosatellite at chromosome 4q35. Epigenetic derepression permits the distal-most D4Z4 unit to transcribe DUX4, with transcripts stabilised by splicing to a poly(A) signal on permissive 4qA haplotypes. The pioneer transcription factor DUX4 activates target genes that are proposed to drive FSHD pathology. While this toxic gain-of-function model is a satisfying "bottom-up" genotype-to-phenotype link, DUX4 is rarely detectable in muscle and DUX4 target gene expression is inconsistent in patients. A reliable biomarker for FSHD is suppression of a target gene score of PAX7, a master regulator of myogenesis. However, it is unclear how this "top-down" finding links to genomic changes that characterise FSHD and to DUX4. Here, we explore the roles and interactions of DUX4 and PAX7 in FSHD pathology and how the relationship between these two transcription factors deepens understanding via the immune system and muscle regeneration. Considering how FSHD pathomechanisms are represented by "DUX4opathy" models has implications for developing therapies and current clinical trials.
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Affiliation(s)
| | - Peter S Zammit
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
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15
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Good Outcome for an Individual with Severe Facial Anomalies and Hypogonadotropic Hypogonadism: A Consequence of His Cognitive Function, Pragmatic Approach, and Temperament. Case Rep Pediatr 2021; 2021:9957218. [PMID: 34194860 PMCID: PMC8214474 DOI: 10.1155/2021/9957218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/27/2021] [Accepted: 05/29/2021] [Indexed: 11/18/2022] Open
Abstract
The multiple factors that determine outcomes for individuals with visible developmental errors and/or atypical development of the reproductive system are not fully understood. This case report of an individual with Bosma arhinia microphthalmia syndrome causing severe facial anomalies and hypogonadotropic hypogonadism is used to highlight factors that impacted his adjustment from childhood through adulthood. Key factors include his temperament, intact cognitive ability, and pragmatic approach for controlling his physical and social environment. His successful adjustment even in the face of significant early life challenges demonstrates that positive outcomes are attainable for individuals with significant developmental errors. His story and experiences with the health-care system offer insight into some factors that may be pertinent to resilience and lifelong adjustment for patients with similar conditions and the importance of continually seeking the patient's perspective to tailor treatment across the lifespan.
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16
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Relating SMCHD1 structure to its function in epigenetic silencing. Biochem Soc Trans 2021; 48:1751-1763. [PMID: 32779700 PMCID: PMC7458401 DOI: 10.1042/bst20200242] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 02/07/2023]
Abstract
The structural maintenance of chromosomes hinge domain containing protein 1 (SMCHD1) is a large multidomain protein involved in epigenetic gene silencing. Variations in the SMCHD1 gene are associated with two debilitating human disorders, facioscapulohumeral muscular dystrophy (FSHD) and Bosma arhinia microphthalmia syndrome (BAMS). Failure of SMCHD1 to silence the D4Z4 macro-repeat array causes FSHD, yet the consequences on gene silencing of SMCHD1 variations associated with BAMS are currently unknown. Despite the interest due to these roles, our understanding of the SMCHD1 protein is in its infancy. Most knowledge of SMCHD1 function is based on its similarity to the structural maintenance of chromosomes (SMC) proteins, such as cohesin and condensin. SMC proteins and SMCHD1 share similar domain organisation and affect chromatin conformation. However, there are important differences between the domain architectures of SMC proteins and SMCHD1, which distinguish SMCHD1 as a non-canonical member of the family. In the last year, the crystal structures of the two key domains crucial to SMCHD1 function, the ATPase and hinge domains, have emerged. These structures reveal new insights into how SMCHD1 may bind and regulate chromatin structure, and address how amino acid variations in SMCHD1 may contribute to BAMS and FSHD. Here, we contrast SMCHD1 with canonical SMC proteins, and relate the ATPase and hinge domain structures to their roles in SMCHD1-mediated epigenetic silencing and disease.
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17
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Schätzl T, Kaiser L, Deigner HP. Facioscapulohumeral muscular dystrophy: genetics, gene activation and downstream signalling with regard to recent therapeutic approaches: an update. Orphanet J Rare Dis 2021; 16:129. [PMID: 33712050 PMCID: PMC7953708 DOI: 10.1186/s13023-021-01760-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 02/25/2021] [Indexed: 12/12/2022] Open
Abstract
Whilst a disease-modifying treatment for Facioscapulohumeral muscular dystrophy (FSHD) does not exist currently, recent advances in complex molecular pathophysiology studies of FSHD have led to possible therapeutic approaches for its targeted treatment. Although the underlying genetics of FSHD have been researched extensively, there remains an incomplete understanding of the pathophysiology of FSHD in relation to the molecules leading to DUX4 gene activation and the downstream gene targets of DUX4 that cause its toxic effects. In the context of the local proximity of chromosome 4q to the nuclear envelope, a contraction of the D4Z4 macrosatellite induces lower methylation levels, enabling the ectopic expression of DUX4. This disrupts numerous signalling pathways that mostly result in cell death, detrimentally affecting skeletal muscle in affected individuals. In this regard different options are currently explored either to suppress the transcription of DUX4 gene, inhibiting DUX4 protein from its toxic effects, or to alleviate the symptoms triggered by its numerous targets.
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Affiliation(s)
- Teresa Schätzl
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany
| | - Lars Kaiser
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstraße 25, 79104, Freiburg i. Br., Germany
| | - Hans-Peter Deigner
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany.
- EXIM Department, Fraunhofer Institute IZI, Leipzig, Schillingallee 68, 18057, Rostock, Germany.
- Faculty of Science, Tuebingen University, Auf der Morgenstelle 8, 72076, Tübingen, Germany.
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Lemmers RJLF, van der Vliet PJ, Blatnik A, Balog J, Zidar J, Henderson D, Goselink R, Tapscott SJ, Voermans NC, Tawil R, Padberg GWAM, van Engelen BG, van der Maarel SM. Chromosome 10q-linked FSHD identifies DUX4 as principal disease gene. J Med Genet 2021; 59:180-188. [PMID: 33436523 DOI: 10.1136/jmedgenet-2020-107041] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 10/05/2020] [Accepted: 11/14/2020] [Indexed: 01/24/2023]
Abstract
BACKGROUND Facioscapulohumeral dystrophy (FSHD) is an inherited muscular dystrophy clinically characterised by muscle weakness starting with the facial and upper extremity muscles. A disease model has been developed that postulates that failure in somatic repression of the transcription factor DUX4 embedded in the D4Z4 repeat on chromosome 4q causes FSHD. However, due to the position of the D4Z4 repeat close to the telomere and the complex genetic and epigenetic aetiology of FSHD, there is ongoing debate about the transcriptional deregulation of closely linked genes and their involvement in FSHD. METHOD Detailed genetic characterisation and gene expression analysis of patients with clinically confirmed FSHD and control individuals. RESULTS Identification of two FSHD families in which the disease is caused by repeat contraction and DUX4 expression from chromosome 10 due to a de novo D4Z4 repeat exchange between chromosomes 4 and 10. We show that the genetic lesion causal to FSHD in these families is physically separated from other candidate genes on chromosome 4. We demonstrate that muscle cell cultures from affected family members exhibit the characteristic molecular features of FSHD, including DUX4 and DUX4 target gene expression, without showing evidence for transcriptional deregulation of other chromosome 4-specific candidate genes. CONCLUSION This study shows that in rare situations, FSHD can occur on chromosome 10 due to an interchromosomal rearrangement with the FSHD locus on chromosome 4q. These findings provide further evidence that DUX4 derepression is the dominant disease pathway for FSHD. Hence, therapeutic strategies should focus on DUX4 as the primary target.
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Affiliation(s)
- Richard J L F Lemmers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Ana Blatnik
- Cancer Genetics Clinic, Institute of Oncology, Ljubljana, Slovenia
| | - Judit Balog
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Janez Zidar
- Division of Neurology, Institute of Clinical Neurophysiology, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Don Henderson
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - Rianne Goselink
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Stephen J Tapscott
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Nicol C Voermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
| | - George W A M Padberg
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Baziel Gm van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
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Bouwman LF, den Hamer B, Verveer EP, Lerink LJS, Krom YD, van der Maarel SM, de Greef JC. Dnmt3b regulates DUX4 expression in a tissue-dependent manner in transgenic D4Z4 mice. Skelet Muscle 2020; 10:27. [PMID: 33004076 PMCID: PMC7528343 DOI: 10.1186/s13395-020-00247-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 09/10/2020] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Facioscapulohumeral muscular dystrophy (FSHD) is a skeletal muscle disorder that is caused by derepression of the transcription factor DUX4 in skeletal muscle cells. Apart from SMCHD1, DNMT3B was recently identified as a disease gene and disease modifier in FSHD. However, the exact role of DNMT3B at the D4Z4 repeat array remains unknown. METHODS To determine the role of Dnmt3b on DUX4 repression, hemizygous mice with a FSHD-sized D4Z4 repeat array (D4Z4-2.5 mice) were cross-bred with mice carrying an in-frame exon skipping mutation in Dnmt3b (Dnmt3bMommeD14 mice). Additionally, siRNA knockdowns of Dnmt3b were performed in mouse embryonic stem cells (mESCs) derived from the D4Z4-2.5 mouse model. RESULTS In mESCs derived from D4Z4-2.5 mice, Dnmt3b was enriched at the D4Z4 repeat array and DUX4 transcript levels were upregulated after a knockdown of Dnmt3b. In D4Z4-2.5/Dnmt3bMommeD14 mice, Dnmt3b protein levels were reduced; however, DUX4 RNA levels in skeletal muscles were not enhanced and no pathology was observed. Interestingly, D4Z4-2.5/Dnmt3bMommeD14 mice showed a loss of DNA methylation at the D4Z4 repeat array and significantly higher DUX4 transcript levels in secondary lymphoid organs. As these lymphoid organs seem to be more sensitive to epigenetic modifiers of the D4Z4 repeat array, different immune cell populations were quantified in the spleen and inguinal lymph nodes of D4Z4-2.5 mice crossed with Dnmt3bMommeD14 mice or Smchd1MommeD1 mice. Only in D4Z4-2.5/Smchd1MommeD1 mice the immune cell populations were disturbed. CONCLUSIONS Our data demonstrates that loss of Dnmt3b results in derepression of DUX4 in lymphoid tissues and mESCs but not in myogenic cells of D4Z4-2.5/Dnmt3bMommeD14 mice. In addition, the Smchd1MommeD1 variant seems to have a more potent role in DUX4 derepression. Our studies suggest that the immune system is particularly but differentially sensitive to D4Z4 chromatin modifiers which may provide a molecular basis for the yet underexplored immune involvement in FSHD.
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Affiliation(s)
- Linde F Bouwman
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Bianca den Hamer
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Elwin P Verveer
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Lente J S Lerink
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Yvonne D Krom
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
- Department of Neurology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Silvère M van der Maarel
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands.
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Giacomucci G, Monforte M, Diaz-Manera J, Mul K, Fernandez Torrón R, Maggi L, Marini Bettolo C, Dahlqvist JR, Haberlova J, Camaño P, Gros M, Tartaglione T, Cristiano L, Gerevini S, Calandra P, Deidda G, Giardina E, Sacconi S, Straub V, Vissing J, Van Engelen B, Ricci E, Tasca G. Deep phenotyping of facioscapulohumeral muscular dystrophy type 2 by magnetic resonance imaging. Eur J Neurol 2020; 27:2604-2615. [PMID: 32697863 DOI: 10.1111/ene.14446] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/15/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND PURPOSE The aim was to define the radiological picture of facioscapulohumeral muscular dystrophy 2 (FSHD2) in comparison with FSHD1 and to explore correlations between imaging and clinical/molecular data. METHODS Upper girdle and/or lower limb muscle magnetic resonance imaging scans of 34 molecularly confirmed FSHD2 patients from nine European neuromuscular centres were analysed. T1-weighted and short-tau inversion recovery (STIR) sequences were used to evaluate the global pattern and to assess the extent of fatty replacement and muscle oedema. RESULTS The most frequently affected muscles were obliquus and transversus abdominis, semimembranosus, soleus and gluteus minimus in the lower limbs; trapezius, serratus anterior, latissimus dorsi and pectoralis major in the upper girdle. Iliopsoas, popliteus, obturator internus and tibialis posterior in the lower limbs and subscapularis, spinati, sternocleidomastoid and levator scapulae in the upper girdle were the most spared. Asymmetry and STIR hyperintensities were consistent features. The pattern of muscle involvement was similar to that of FSHD1, and the combined involvement of trapezius, abdominal and hamstring muscles, together with complete sparing of iliopsoas and subscapularis, was detected in 91% of patients. Peculiar differences were identified in a rostro-caudal gradient, a predominant involvement of lower limb muscles compared to the upper girdle, and in the higher percentage of STIR hyperintensities in FSHD2. CONCLUSION This multicentre study defines the pattern of muscle involvement in FSHD2, providing useful information for diagnostics and clinical trial design. Both similarities and differences between FSHD1 and FSHD2 were detected, which is also relevant to better understand the pathogenic mechanisms underlying the FSHD-related disease spectrum.
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Affiliation(s)
- G Giacomucci
- Istituto di Neurologia, Università Cattolica del Sacro Cuore, Roma, Italy
| | - M Monforte
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italy
| | - J Diaz-Manera
- Neuromuscular Disorders Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER), Barcelona, Spain
| | - K Mul
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - R Fernandez Torrón
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.,Neurology Department, Biodonostia Health Research Institute, Neuromuscular Area, Hospital Donostia, Basque Health Service, Doctor Begiristain, Donostia-San Sebastian, Spain
| | - L Maggi
- Neuroimmunology and Neuromuscular Diseases Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - C Marini Bettolo
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - J R Dahlqvist
- Copenhagen Neuromuscular Center, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - J Haberlova
- Department of Pediatric Neurology, 2nd Faculty of Medicine, Charles University in Prague and University Hospital Motol, Prague, Czech Republic
| | - P Camaño
- Biodonostia, Neurosciences Area, Group of Neuromuscular Diseases; Biodonostia-Osakidetza Basque Health Service, Molecular Diagnostics Platform, San Sebastian, Spain
| | - M Gros
- Université Côte d'Azur (UCA), Peripheral Nervous System, Muscle and ALS Department, Pasteur 2 Hospital, Nice, France.,Université Côte d'Azur, Inserm, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - T Tartaglione
- Radiology Unit, Istituto Dermopatico dell'Immacolata-IRCCS-FLMM, Rome, Italy
| | - L Cristiano
- Radiology Unit, Istituto Dermopatico dell'Immacolata-IRCCS-FLMM, Rome, Italy
| | - S Gerevini
- Neuroradiology Department, IRCCS San Raffaele Hospital, Milan, Italy
| | - P Calandra
- Institute of Cell Biology and Neurobiology, National Research Council of Italy, Monterotondo, Rome, Italy
| | - G Deidda
- Institute of Cell Biology and Neurobiology, National Research Council of Italy, Monterotondo, Rome, Italy
| | - E Giardina
- Molecular Genetics Laboratory UILDM, Santa Lucia Foundation IRCSS-University of Rome 'Tor Vergata', Rome, Italy
| | - S Sacconi
- Université Côte d'Azur (UCA), Peripheral Nervous System, Muscle and ALS Department, Pasteur 2 Hospital, Nice, France.,Université Côte d'Azur, Inserm, CNRS, Institute for Research on Cancer and Aging of Nice (IRCAN), Nice, France
| | - V Straub
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - J Vissing
- Copenhagen Neuromuscular Center, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - B Van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - E Ricci
- Istituto di Neurologia, Università Cattolica del Sacro Cuore, Roma, Italy.,Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italy
| | - G Tasca
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italy
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21
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Rare variant of the epigenetic regulator SMCHD1 in a patient with pituitary hormone deficiency. Sci Rep 2020; 10:10985. [PMID: 32620854 PMCID: PMC7335161 DOI: 10.1038/s41598-020-67715-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 06/12/2020] [Indexed: 11/17/2022] Open
Abstract
Isolated hypogonadotropic hypogonadism (IHH), combined pituitary hormone deficiency (CPHD), and septo-optic dysplasia (SOD) constitute a disease spectrum whose etiology remains largely unknown. This study aimed to clarify whether mutations in SMCHD1, an epigenetic regulator gene, might underlie this disease spectrum. SMCHD1 is a causative gene for Bosma arhinia microphthalmia syndrome characterized by arhinia, microphthalmia and IHH. We performed mutation screening of SMCHD1 in patients with etiology-unknown IHH (n = 31) or CPHD (n = 43, 19 of whom also satisfied the SOD diagnostic criteria). Rare variants were subjected to in silico analyses and classified according to the American College of Medical Genetics and Genomics guidelines. Consequently, a rare likely pathogenic variant, p.Asp398Asn, was identified in one patient. The patient with p.Asp398Asn exhibited CPHD, optic nerve hypoplasia, and a thin retinal nerve fiber layer, and therefore satisfied the criteria of SOD. This patient showed a relatively low DNA methylation level of the 52 SMCHD1-target CpG sites at the D4Z4 locus. Exome sequencing for the patient excluded additional variants in other IHH/CPHD-causative genes. In vitro assays suggested functional impairment of the p.Asp398Asn variant. These results provide the first indication that SMCHD1 mutations represent a rare genetic cause of the HH-related disease spectrum.
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22
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Greco A, Goossens R, van Engelen B, van der Maarel SM. Consequences of epigenetic derepression in facioscapulohumeral muscular dystrophy. Clin Genet 2020; 97:799-814. [PMID: 32086799 PMCID: PMC7318180 DOI: 10.1111/cge.13726] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/08/2020] [Accepted: 02/11/2020] [Indexed: 02/06/2023]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD), a common hereditary myopathy, is caused either by the contraction of the D4Z4 macrosatellite repeat at the distal end of chromosome 4q to a size of 1 to 10 repeat units (FSHD1) or by mutations in D4Z4 chromatin modifiers such as Structural Maintenance of Chromosomes Hinge Domain Containing 1 (FSHD2). These two genotypes share a phenotype characterized by progressive and often asymmetric muscle weakening and atrophy, and common epigenetic alterations of the D4Z4 repeat. All together, these epigenetic changes converge the two genetic forms into one disease and explain the derepression of the DUX4 gene, which is otherwise kept epigenetically silent in skeletal muscle. DUX4 is consistently transcriptionally upregulated in FSHD1 and FSHD2 skeletal muscle cells where it is believed to exercise a toxic effect. Here we provide a review of the recent literature describing the progress in understanding the complex genetic and epigenetic architecture of FSHD, with a focus on one of the consequences that these epigenetic changes inflict, the DUX4-induced immune deregulation cascade. Moreover, we review the latest therapeutic strategies, with particular attention to the potential of epigenetic correction of the FSHD locus.
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Affiliation(s)
- Anna Greco
- Department of Neurology, Donders Institute for Brain, Cognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands
- Department of Experimental Internal MedicineRadboud University Medical CenterNijmegenThe Netherlands
| | - Remko Goossens
- Department of Human GeneticsLeiden University Medical CenterLeidenThe Netherlands
| | - Baziel van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and BehaviourRadboud University Medical CenterNijmegenThe Netherlands
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23
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Strafella C, Caputo V, Galota RM, Campoli G, Bax C, Colantoni L, Minozzi G, Orsini C, Politano L, Tasca G, Novelli G, Ricci E, Giardina E, Cascella R. The variability of SMCHD1 gene in FSHD patients: evidence of new mutations. Hum Mol Genet 2020; 28:3912-3920. [PMID: 31600781 PMCID: PMC6969370 DOI: 10.1093/hmg/ddz239] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/10/2019] [Accepted: 09/12/2019] [Indexed: 12/31/2022] Open
Abstract
In this study, we investigated the sequence of (Structural Maintenance of Chromosomes flexible Hinge Domain containing 1) SMCHD1 gene in a cohort of clinically defined FSHD (facioscapulohumeral muscular dystrophy) patients in order to assess the distribution of SMCHD1 variants, considering the D4Z4 fragment size in terms of repeated units (RUs; short fragment: 1–7 RU, borderline: 8-10RU and normal fragment: >11RU). The analysis of SMCHD1 revealed the presence of 82 variants scattered throughout the introns, exons and 3’untranslated region (3′UTR) of the gene. Among them, 64 were classified as benign polymorphisms and 6 as VUS (variants of uncertain significance). Interestingly, seven pathogenic/likely pathogenic variants were identified in patients carrying a borderline or normal D4Z4 fragment size, namely c.182_183dupGT (p.Q62Vfs*48), c.2129dupC (p.A711Cfs*11), c.3469G>T (p.G1157*), c.5150_5151delAA (p.K1717Rfs*16) and c.1131+2_1131+5delTAAG, c.3010A>T (p.K1004*), c.853G>C (p.G285R). All of them were predicted to disrupt the structure and conformation of SMCHD1, resulting in the loss of GHKL-ATPase and SMC hinge essential domains. These results are consistent with the FSHD symptomatology and the Clinical Severity Score (CSS) of patients. In addition, five variants (c.*1376A>C, rs7238459; c.*1579G>A, rs559994; c.*1397A>G, rs150573037; c.*1631C>T, rs193227855; c.*1889G>C, rs149259359) were identified in the 3′UTR region of SMCHD1, suggesting a possible miRNA-dependent regulatory effect on FSHD-related pathways. The present study highlights the clinical utility of next-generation sequencing (NGS) platforms for the molecular diagnosis of FSHD and the importance of integrating molecular findings and clinical data in order to improve the accuracy of genotype–phenotype correlations.
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Affiliation(s)
- Claudia Strafella
- Genomic Medicine Laboratory UILDM, Santa Lucia Foundation, Rome, 00142, Italy.,Department of Biomedicine and Prevention, Tor Vergata University, Rome, 00133, Italy
| | - Valerio Caputo
- Department of Biomedicine and Prevention, Tor Vergata University, Rome, 00133, Italy
| | | | - Giulia Campoli
- Genomic Medicine Laboratory UILDM, Santa Lucia Foundation, Rome, 00142, Italy
| | - Cristina Bax
- Genomic Medicine Laboratory UILDM, Santa Lucia Foundation, Rome, 00142, Italy
| | - Luca Colantoni
- Genomic Medicine Laboratory UILDM, Santa Lucia Foundation, Rome, 00142, Italy
| | - Giulietta Minozzi
- Department of Veterinary Medicine (DIMEVET), University of Milan, Milan, 20100, Italy
| | - Chiara Orsini
- vCardiomyology and Medical Genetics, Department of Experimental Medicine, University of Campania Luigi Vanvitelli, Naples, 80131, Italy
| | - Luisa Politano
- vCardiomyology and Medical Genetics, Department of Experimental Medicine, University of Campania Luigi Vanvitelli, Naples, 80131, Italy
| | - Giorgio Tasca
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, 00168, Italy
| | - Giuseppe Novelli
- Department of Biomedicine and Prevention, Tor Vergata University, Rome, 00133, Italy.,Neuromed Institute IRCCS, Pozzilli, 86077, Italy
| | - Enzo Ricci
- Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, 00168, Italy.,Istituto di Neurologia, Università Cattolica del Sacro Cuore, Rome, 00168, Italy
| | - Emiliano Giardina
- Genomic Medicine Laboratory UILDM, Santa Lucia Foundation, Rome, 00142, Italy.,Department of Biomedicine and Prevention, Tor Vergata University, Rome, 00133, Italy
| | - Raffaella Cascella
- Department of Biomedicine and Prevention, Tor Vergata University, Rome, 00133, Italy.,Department of Biomedical Sciences, Catholic University Our Lady of Good Counsel, Tirana, 1000, Albania
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24
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Magdinier F, Nguyen K, Attarian S. [Marseille welcomes the FSHD Society International Research Conference]. Med Sci (Paris) 2019; 35 Hors série n° 2:55-59. [PMID: 31859637 DOI: 10.1051/medsci/2019184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Les 19 et 20 juin 2019, la conférence internationale sur la recherche dans la dystrophie facio-scapulo-humérale (FSHD) a eu lieu à Marseille. La rencontre rassemblant 180 participants, médecins, scientifiques et patients était organisée au Palais du Pharo à Marseille. Ce site historique emblématique surplombant le Vieux Port et faisant face à Notre Dame de la Garde a été construit dans la seconde moitié du XIXe siècle par Napoléon III pour son épouse, l’impératrice Eugénie.
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Affiliation(s)
| | - Karine Nguyen
- Aix Marseille Univ, Inserm, MMG, Marseille Medical Genetics, Marseille, France - Département de génétique Médicale, Hôpital de la Timone, Marseille, France
| | - Shahram Attarian
- Aix Marseille Univ, Inserm, MMG, Marseille Medical Genetics, Marseille, France - Centre de référence pour les maladies neuromusculaires et la SLA, Hôpital de la Timone, Marseille, France - Filnemus, Filière Neuromusculaire,
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25
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Goossens R, van den Boogaard ML, Lemmers RJLF, Balog J, van der Vliet PJ, Willemsen IM, Schouten J, Maggio I, van der Stoep N, Hoeben RC, Tapscott SJ, Geijsen N, Gonçalves MAFV, Sacconi S, Tawil R, van der Maarel SM. Intronic SMCHD1 variants in FSHD: testing the potential for CRISPR-Cas9 genome editing. J Med Genet 2019; 56:828-837. [PMID: 31676591 DOI: 10.1136/jmedgenet-2019-106402] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/04/2019] [Accepted: 09/21/2019] [Indexed: 01/14/2023]
Abstract
BACKGROUND Facioscapulohumeral dystrophy (FSHD) is associated with partial chromatin relaxation of the DUX4 retrogene containing D4Z4 macrosatellite repeats on chromosome 4, and transcriptional de-repression of DUX4 in skeletal muscle. The common form of FSHD, FSHD1, is caused by a D4Z4 repeat array contraction. The less common form, FSHD2, is generally caused by heterozygous variants in SMCHD1. METHODS We employed whole exome sequencing combined with Sanger sequencing to screen uncharacterised FSHD2 patients for extra-exonic SMCHD1 mutations. We also used CRISPR-Cas9 genome editing to repair a pathogenic intronic SMCHD1 variant from patient myoblasts. RESULTS We identified intronic SMCHD1 variants in two FSHD families. In the first family, an intronic variant resulted in partial intron retention and inclusion of the distal 14 nucleotides of intron 13 into the transcript. In the second family, a deep intronic variant in intron 34 resulted in exonisation of 53 nucleotides of intron 34. In both families, the aberrant transcripts are predicted to be non-functional. Deleting the pseudo-exon by CRISPR-Cas9 mediated genome editing in primary and immortalised myoblasts from the index case of the second family restored wild-type SMCHD1 expression to a level that resulted in efficient suppression of DUX4. CONCLUSIONS The estimated intronic mutation frequency of almost 2% in FSHD2, as exemplified by the two novel intronic SMCHD1 variants identified here, emphasises the importance of screening for intronic variants in SMCHD1. Furthermore, the efficient suppression of DUX4 after restoring SMCHD1 levels by genome editing of the mutant allele provides further guidance for therapeutic strategies.
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Affiliation(s)
- Remko Goossens
- Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - Judit Balog
- Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Iris M Willemsen
- Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Julie Schouten
- Hubrecht Institute-KNAW and University Medical Center, Utrecht, The Netherlands.,Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht, The Netherlands
| | - Ignazio Maggio
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands.,Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands
| | - Nienke van der Stoep
- Center for Human and Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Rob C Hoeben
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Stephen J Tapscott
- Division of Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Niels Geijsen
- Hubrecht Institute-KNAW and University Medical Center, Utrecht, The Netherlands.,Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht, The Netherlands
| | - Manuel A F V Gonçalves
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Sabrina Sacconi
- Peripheral Nervous System, Muscle and ALS Department, Université Côte d'Azur, Nice, France.,Institute for Research on Cancer and Aging of Nice, Faculty of Medicine, Université Côte d'Azur, Nice, France
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA
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26
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26th Annual Facioscapulohumeral Dystrophy International Research Congress Marseille, France, 19-20 June 2019. Neuromuscul Disord 2019; 29:811-817. [PMID: 31604652 DOI: 10.1016/j.nmd.2019.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/28/2019] [Indexed: 11/23/2022]
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