1
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Gaudet MV, Allain EP, Gallant LM, Arts HH, Ben Amor M. A 132 bp deletion affecting the KCNQ1OT1 gene associated with Silver-Russell syndrome clinical phenotype. J Med Genet 2023; 60:134-136. [PMID: 35772847 PMCID: PMC9887386 DOI: 10.1136/jmedgenet-2021-108288] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 03/08/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND Imprinting centre 2 (IC2) in the chromosomal region 11p15.5 regulates the monoallelic expression of imprinted genes by differential methylation of paternal and maternal chromosomes. Copy number variants in IC2 are associated with Beckwith-Wiedemann syndrome and Silver-Russell syndrome (SRS). Clinical outcome of IC2 deletions seems to depend on the parental origin of the chromosome, deletion size and inclusion or exclusion of enhancer and promoter regions. RESULTS A paternally inherited 132 bp deletion within the KCNQ1OT1 gene was found in a proband with an SRS clinical phenotype. The patient's father and paternal grandmother, who both carry the deletion on their maternal chromosome, are unaffected. Review of other IC2 deletions and their associated clinical presentation was useful in understanding the genetic-phenotypic correlation. CONCLUSION Only six cases have been reported with deletions involving exclusively IC2, one being identical to our proband's 132 bp deletion. Our study, which is based on more extensive segregation data than the previous 132 bp deletion report, confirms the association of this deletion with growth restriction when paternally inherited. Remarkably, even though our patient has the same deletion, he has more pronounced phenotypic features; our findings thus suggest that some degree of clinical variability may be associated with this loss.
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Affiliation(s)
- Marie Véronique Gaudet
- Centre de Formation Médicale du Nouveau-Brunswick (Moncton Univerisity), Moncton, New Brunswick, Canada
| | - Eric Pierre Allain
- Medical Genetics, Vitalite Health Network, Moncton, New Brunswick, Canada,Atlantic Cancer Research Institute, Moncton, New Brunswick, Canada
| | - Lynne M Gallant
- Clinical Genomics Laboratory, IWK Health Centre, Halifax, Nova Scotia, Canada
| | - Heleen H Arts
- Clinical Genomics Laboratory, IWK Health Centre, Halifax, Nova Scotia, Canada,Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Mouna Ben Amor
- Medical Genetics, Vitalite Health Network, Moncton, New Brunswick, Canada
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2
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Hara-Isono K, Yamazawa K, Tanaka S, Nishi E, Fukami M, Kagami M. CDKN1C hyperexpression in two patients with severe growth failure and microdeletions affecting the paternally inherited KCNQ1OT1:TSS-DMR. J Med Genet 2022; 59:1241-1246. [PMID: 35906012 DOI: 10.1136/jmg-2022-108700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 07/19/2022] [Indexed: 01/12/2023]
Abstract
BACKGROUND Two imprinting control centres, H19/IGF2:IG-differentialy methylated region (DMR) and KCNQ1OT1:TSS-DMR, reside on chromosome 11p15.5. Paternal deletions involving the KCNQ1OT1:TSS-DMR result in variable phenotypes, namely, normal phenotype, Silver-Russel syndrome (SRS) and fetal demise. However, expression analyses for CDKN1C in these patients are very limited. CASES Patient 1 (adult woman) and patient 2 (boy in early childhood) showed prenatal and postnatal growth failure and clinical suspicion of SRS. MOLECULAR ANALYSES Both patients showed hypermethylation of the KCNQ1OT1:TSS-DMR caused by the paternal heterozygous de novo deletions involving the KCNQ1OT1:TSS-DMR, but not including CDKN1C enhancers. The deletion sizes were 5 kb and 12 kb for patients 1 and 2, respectively. CDKN1C gene expressions in immortalised leucocytes of both patients were increased compared with those of controls. CONCLUSION Paternal deletions involving the KCNQ1OT1:TSS-DMR, but not including CDKN1C enhancers, disrupt KCNQ1OT1 expression, strongly activate CDKN1C expression and consequently cause severe growth failure.
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Affiliation(s)
- Kaori Hara-Isono
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.,Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan
| | - Kazuki Yamazawa
- Medical Genetics Center, National Hospital Organisation Tokyo Medical Center, Tokyo, Japan
| | - Satsuki Tanaka
- Department of Diabetes and Endocrinology, Osaka Saiseikai Nakatsu Hospital, Osaka, Japan
| | - Eriko Nishi
- Department of Medical Genetics, Osaka Women's and Children's Hospital, Izumi, Japan
| | - Maki Fukami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
| | - Masayo Kagami
- Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan
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3
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Eosinophilic Infiltration of the Sino-Atrial Node in Sudden Cardiac Death Caused by Long QT Syndrome. Int J Mol Sci 2022; 23:ijms231911666. [PMID: 36232963 PMCID: PMC9569895 DOI: 10.3390/ijms231911666] [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: 08/31/2022] [Revised: 09/25/2022] [Accepted: 09/28/2022] [Indexed: 11/09/2022] Open
Abstract
Sudden death is defined as the unexpected death of a healthy person that occurs within the first hour of the onset of symptoms or within 24 h of the victim being last seen alive. In some of these cases, rare deleterious variants of genes associated with inherited cardiac disorders can provide a highly probable explanation for the fatal event. We report the case of a 21-year-old obese woman who lost consciousness suddenly in a public place and was pronounced dead after hospital admission. Clinical autopsy showed an inconclusive gross examination, while in the histopathological analysis an eosinophilic inflammatory focus and interstitial fibrosis in the sino-atrial node were found. Molecular autopsy revealed an intronic variant in the KCNQ1 gene (c.683 + 5G > A), classified as likely pathogenic for long QT syndrome according to the guidelines provided by the American College of Medical Genetics and Genomics. Therefore, there were many anomalies that could have played a role in the causation of the sudden death, such as the extreme obesity, the cardiac anomalies and the KNCQ1 variant. This case depicts the difficult interpretation of rare cardiac structural abnormalities in subjects carrying rare variants responsible for inherited arrhythmic disorders and the challenge for the forensic pathologist to make causal inferences in the determinism of the unexpected decease.
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4
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Lin Y, Huang J, Zhu Z, Zhang Z, Xian J, Yang Z, Qin T, Chen L, Huang J, Huang Y, Wu Q, Hu Z, Lin X, Xu G. Overlap phenotypes of the left ventricular noncompaction and hypertrophic cardiomyopathy with complex arrhythmias and heart failure induced by the novel truncated DSC2 mutation. Orphanet J Rare Dis 2021; 16:496. [PMID: 34819141 PMCID: PMC8611834 DOI: 10.1186/s13023-021-02112-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/06/2021] [Indexed: 12/18/2022] Open
Abstract
Background The left ventricular noncompaction cardiomyopathy (LVNC) is a rare subtype of cardiomyopathy associated with a high risk of heart failure (HF), thromboembolism, arrhythmia, and sudden cardiac death. Methods The proband with overlap phenotypes of LVNC and hypertrophic cardiomyopathy (HCM) complicates atrial fibrillation (AF), ventricular tachycardia (VT), and HF due to the diffuse myocardial lesion, which were diagnosed by electrocardiogram, echocardiogram and cardiac magnetic resonance imaging. Peripheral blood was collected from the proband and his relatives. DNA was extracted from the peripheral blood of proband for high-throughput target capture sequencing. The Sanger sequence verified the variants. The protein was extracted from the skin of the proband and healthy volunteer. The expression difference of desmocollin2 was detected by Western blot. Results The novel heterozygous truncated mutation (p.K47Rfs*2) of the DSC2 gene encoding an important component of desmosomes was detected by targeted capture sequencing. The western blots showed that the expressing level of functional desmocollin2 protein (~ 94kd) was lower in the proband than that in the healthy volunteer, indicating that DSC2 p.K47Rfs*2 obviously reduced the functional desmocollin2 protein expression in the proband. Conclusion The heterozygous DSC2 p.K47Rfs*2 remarkably and abnormally reduced the functional desmocollin2 expression, which may potentially induce the overlap phenotypes of LVNC and HCM, complicating AF, VT, and HF.
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Affiliation(s)
- Yubi Lin
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Jiana Huang
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China.,Reproductive Center, The Six Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510000, China
| | - Zhiling Zhu
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Zuoquan Zhang
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Jianzhong Xian
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Zhe Yang
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Tingfeng Qin
- Department of Physiology, The School of Medicine of Jinan University, Guangzhou, 510000, China
| | - Linxi Chen
- Department of Physiology, The School of Medicine of Jinan University, Guangzhou, 510000, China
| | - Jingmin Huang
- Department of Physiology, The School of Medicine of Jinan University, Guangzhou, 510000, China
| | - Yin Huang
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Qiaoyun Wu
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China
| | - Zhenyu Hu
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Xiufang Lin
- The Center of Cardiovascular Diseases, The Department of Cardiology, Radiology and Ultrasonography, Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, 519000, China.
| | - Geyang Xu
- Department of Physiology, The School of Medicine of Jinan University, Guangzhou, 510000, China.
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5
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Prekovic S, Schuurman K, Mayayo-Peralta I, Manjón AG, Buijs M, Yavuz S, Wellenstein MD, Barrera A, Monkhorst K, Huber A, Morris B, Lieftink C, Chalkiadakis T, Alkan F, Silva J, Győrffy B, Hoekman L, van den Broek B, Teunissen H, Debets DO, Severson T, Jonkers J, Reddy T, de Visser KE, Faller W, Beijersbergen R, Altelaar M, de Wit E, Medema R, Zwart W. Glucocorticoid receptor triggers a reversible drug-tolerant dormancy state with acquired therapeutic vulnerabilities in lung cancer. Nat Commun 2021; 12:4360. [PMID: 34272384 PMCID: PMC8285479 DOI: 10.1038/s41467-021-24537-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 06/24/2021] [Indexed: 12/13/2022] Open
Abstract
The glucocorticoid receptor (GR) regulates gene expression, governing aspects of homeostasis, but is also involved in cancer. Pharmacological GR activation is frequently used to alleviate therapy-related side-effects. While prior studies have shown GR activation might also have anti-proliferative action on tumours, the underpinnings of glucocorticoid action and its direct effectors in non-lymphoid solid cancers remain elusive. Here, we study the mechanisms of glucocorticoid response, focusing on lung cancer. We show that GR activation induces reversible cancer cell dormancy characterised by anticancer drug tolerance, and activation of growth factor survival signalling accompanied by vulnerability to inhibitors. GR-induced dormancy is dependent on a single GR-target gene, CDKN1C, regulated through chromatin looping of a GR-occupied upstream distal enhancer in a SWI/SNF-dependent fashion. These insights illustrate the importance of GR signalling in non-lymphoid solid cancer biology, particularly in lung cancer, and warrant caution for use of glucocorticoids in treatment of anticancer therapy related side-effects.
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Affiliation(s)
- Stefan Prekovic
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| | - Karianne Schuurman
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Isabel Mayayo-Peralta
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Anna G Manjón
- Division of Cell Biology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Mark Buijs
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Selçuk Yavuz
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Max D Wellenstein
- Division of Tumour Biology and Immunology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Alejandro Barrera
- Department of Biostatistics & Bioinformatics, and Centre for Genomic & Computational Biology, Duke University Medical Centre, Durham, NC, USA
| | - Kim Monkhorst
- Department of Pathology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Anne Huber
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,Olivia Newton-John Cancer Research Institute and School of Cancer Medicine, La Trobe University, Melbourne, VIC, Australia
| | - Ben Morris
- Division of Molecular Carcinogenesis and Robotics and Screening Centre, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Cor Lieftink
- Division of Molecular Carcinogenesis and Robotics and Screening Centre, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Theofilos Chalkiadakis
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Ferhat Alkan
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Joana Silva
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Balázs Győrffy
- Semmelweis University Department of Bioinformatics and 2nd Department of Pediatrics, Budapest, Hungary.,TTK Cancer Biomarker Research Group, Institute of Enzymology, Budapest, Hungary
| | - Liesbeth Hoekman
- Mass spectrometry/Proteomics Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Bram van den Broek
- Division of Cell Biology and BioImaging Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Hans Teunissen
- Division of Gene Regulation, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Donna O Debets
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Tesa Severson
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Jos Jonkers
- Division of Molecular Pathology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Timothy Reddy
- Department of Biostatistics & Bioinformatics, and Centre for Genomic & Computational Biology, Duke University Medical Centre, Durham, NC, USA
| | - Karin E de Visser
- Division of Tumour Biology and Immunology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - William Faller
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Roderick Beijersbergen
- Division of Molecular Carcinogenesis and Robotics and Screening Centre, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Maarten Altelaar
- Mass spectrometry/Proteomics Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands.,Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands
| | - Elzo de Wit
- Division of Gene Regulation, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Rene Medema
- Division of Cell Biology, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Wilbert Zwart
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, The Netherlands. .,Laboratory of Chemical Biology and Institute for Complex Molecular Systems, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
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6
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Naveh NSS, Deegan DF, Huhn J, Traxler E, Lan Y, Weksberg R, Ganguly A, Engel N, Kalish JM. The role of CTCF in the organization of the centromeric 11p15 imprinted domain interactome. Nucleic Acids Res 2021; 49:6315-6330. [PMID: 34107024 PMCID: PMC8216465 DOI: 10.1093/nar/gkab475] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 04/22/2021] [Accepted: 05/20/2021] [Indexed: 02/06/2023] Open
Abstract
DNA methylation, chromatin-binding proteins, and DNA looping are common components regulating genomic imprinting which leads to parent-specific monoallelic gene expression. Loss of methylation (LOM) at the human imprinting center 2 (IC2) on chromosome 11p15 is the most common cause of the imprinting overgrowth disorder Beckwith-Wiedemann Syndrome (BWS). Here, we report a familial transmission of a 7.6 kB deletion that ablates the core promoter of KCNQ1. This structural alteration leads to IC2 LOM and causes recurrent BWS. We find that occupancy of the chromatin organizer CTCF is disrupted proximal to the deletion, which causes chromatin architecture changes both in cis and in trans. We also profile the chromatin architecture of IC2 in patients with sporadic BWS caused by isolated LOM to identify conserved features of IC2 regulatory disruption. A strong interaction between CTCF sites around KCNQ1 and CDKN1C likely drive their expression on the maternal allele, while a weaker interaction involving the imprinting control region element may impede this connection and mediate gene silencing on the paternal allele. We present an imprinting model in which KCNQ1 transcription is necessary for appropriate CTCF binding and a novel chromatin conformation to drive allele-specific gene expression.
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Affiliation(s)
- Natali S Sobel Naveh
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Daniel F Deegan
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Jacklyn Huhn
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Emily Traxler
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Yemin Lan
- Epigenetics Institute, Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rosanna Weksberg
- Division of Clinical and Metabolic Genetics, Genetics and Genome Biology, Hospital for Sick Children, and Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Arupa Ganguly
- Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nora Engel
- Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 19140, USA
| | - Jennifer M Kalish
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.,Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Grassi S, Vidal MC, Campuzano O, Arena V, Alfonsetti A, Rossi SS, Scarnicci F, Iglesias A, Brugada R, Oliva A. Sudden Death without a Clear Cause after Comprehensive Investigation: An Example of Forensic Approach to Atypical/Uncertain Findings. Diagnostics (Basel) 2021; 11:diagnostics11050886. [PMID: 34067575 PMCID: PMC8156818 DOI: 10.3390/diagnostics11050886] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/18/2022] Open
Abstract
Sudden death (SD) is defined as the unexpected natural death occurred within an hour after the onset of symptoms or from the last moment the subject has been seen in a healthy condition. Brugada syndrome (BrS) is one of the most remarkable cardiac causes of SD among young people. We report the case of a 20-year-old man who suddenly died after reportedly having smoked cannabis. Autopsy, toxicology, and genetic testing were performed. Autopsy found a long and thick myocardial bridging (MB) at 2 cm from the beginning of the left anterior descending coronary artery. Furthermore, at the histopathological examination, fibrosis and disarray in myocardial area above the MB, fatty tissue in the right ventricle and fibrosis of the sino-atrial node area were found. Toxicology testing was inconclusive, while genetic testing found a rare missense variant of the TTN gene, classified as likely benign, and a variant of unknown significance in the SLMAP gene (a gene that can be associated with BrS). Hence, despite several atypical features were found, no inference on the cause of the death could be made under current evidence.
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Affiliation(s)
- Simone Grassi
- Section of Legal Medicine, Department of Health Surveillance and Bioethics, Catholic University of the Sacred Heart, 00168 Rome, Italy; (A.A.); (S.S.R.); (F.S.); (A.O.)
- Correspondence: ; Tel.: +39-0630154398
| | - Mònica Coll Vidal
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17290 Salt, Girona, Spain; (M.C.V.); (O.C.); (A.I.); (R.B.)
| | - Oscar Campuzano
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17290 Salt, Girona, Spain; (M.C.V.); (O.C.); (A.I.); (R.B.)
| | - Vincenzo Arena
- Institute of Anatomical Pathology, Department of Woman and Child Health and Public Health, Catholic University of the Sacred Heart, 00168 Rome, Italy;
| | - Alessandro Alfonsetti
- Section of Legal Medicine, Department of Health Surveillance and Bioethics, Catholic University of the Sacred Heart, 00168 Rome, Italy; (A.A.); (S.S.R.); (F.S.); (A.O.)
| | - Sabina Strano Rossi
- Section of Legal Medicine, Department of Health Surveillance and Bioethics, Catholic University of the Sacred Heart, 00168 Rome, Italy; (A.A.); (S.S.R.); (F.S.); (A.O.)
| | - Francesca Scarnicci
- Section of Legal Medicine, Department of Health Surveillance and Bioethics, Catholic University of the Sacred Heart, 00168 Rome, Italy; (A.A.); (S.S.R.); (F.S.); (A.O.)
| | - Anna Iglesias
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17290 Salt, Girona, Spain; (M.C.V.); (O.C.); (A.I.); (R.B.)
| | - Ramon Brugada
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17290 Salt, Girona, Spain; (M.C.V.); (O.C.); (A.I.); (R.B.)
| | - Antonio Oliva
- Section of Legal Medicine, Department of Health Surveillance and Bioethics, Catholic University of the Sacred Heart, 00168 Rome, Italy; (A.A.); (S.S.R.); (F.S.); (A.O.)
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8
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Grassi S, Campuzano O, Coll M, Cazzato F, Sarquella-Brugada G, Rossi R, Arena V, Brugada J, Brugada R, Oliva A. Update on the Diagnostic Pitfalls of Autopsy and Post-Mortem Genetic Testing in Cardiomyopathies. Int J Mol Sci 2021; 22:ijms22084124. [PMID: 33923560 PMCID: PMC8074148 DOI: 10.3390/ijms22084124] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/04/2021] [Accepted: 04/14/2021] [Indexed: 02/08/2023] Open
Abstract
Inherited cardiomyopathies are frequent causes of sudden cardiac death (SCD), especially in young patients. Despite at the autopsy they usually have distinctive microscopic and/or macroscopic diagnostic features, their phenotypes may be mild or ambiguous, possibly leading to misdiagnoses or missed diagnoses. In this review, the main differential diagnoses of hypertrophic cardiomyopathy (e.g., athlete's heart, idiopathic left ventricular hypertrophy), arrhythmogenic cardiomyopathy (e.g., adipositas cordis, myocarditis) and dilated cardiomyopathy (e.g., acquired forms of dilated cardiomyopathy, left ventricular noncompaction) are discussed. Moreover, the diagnostic issues in SCD victims affected by phenotype-negative hypertrophic cardiomyopathy and the relationship between myocardial bridging and hypertrophic cardiomyopathy are analyzed. Finally, the applications/limits of virtopsy and post-mortem genetic testing in this field are discussed, with particular attention to the issues related to the assessment of the significance of the genetic variants.
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Affiliation(s)
- Simone Grassi
- Department of Health Surveillance and Bioethics, Section of Legal Medicine, Fondazione Policlinico A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (F.C.); (R.R.); (A.O.)
- Correspondence:
| | - Oscar Campuzano
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (O.C.); (M.C.); (J.B.); (R.B.)
- Cardiovascular Genetics Center, Institut d’Investigació Biomèdica Girona (IDIBGI), University of Girona, 17190 Girona, Spain
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
| | - Mònica Coll
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (O.C.); (M.C.); (J.B.); (R.B.)
- Cardiovascular Genetics Center, Institut d’Investigació Biomèdica Girona (IDIBGI), University of Girona, 17190 Girona, Spain
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
| | - Francesca Cazzato
- Department of Health Surveillance and Bioethics, Section of Legal Medicine, Fondazione Policlinico A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (F.C.); (R.R.); (A.O.)
| | - Georgia Sarquella-Brugada
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain
| | - Riccardo Rossi
- Department of Health Surveillance and Bioethics, Section of Legal Medicine, Fondazione Policlinico A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (F.C.); (R.R.); (A.O.)
| | - Vincenzo Arena
- Area of Pathology, Department of Woman and Child Health and Public Health, Fondazione Policlinico Universitario A. Gemelli IRCCS, 00147 Rome, Italy;
- Istituto di Anatomia Patologica, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Josep Brugada
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (O.C.); (M.C.); (J.B.); (R.B.)
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain
- Institut Clínic Cardiovascular (ICCV), Hospital Clínic, Universitat de Barcelona, Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
| | - Ramon Brugada
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (O.C.); (M.C.); (J.B.); (R.B.)
- Cardiovascular Genetics Center, Institut d’Investigació Biomèdica Girona (IDIBGI), University of Girona, 17190 Girona, Spain
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
| | - Antonio Oliva
- Department of Health Surveillance and Bioethics, Section of Legal Medicine, Fondazione Policlinico A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, 00168 Rome, Italy; (F.C.); (R.R.); (A.O.)
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9
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Clinical and Molecular Diagnosis of Beckwith-Wiedemann Syndrome with Single- or Multi-Locus Imprinting Disturbance. Int J Mol Sci 2021; 22:ijms22073445. [PMID: 33810554 PMCID: PMC8036922 DOI: 10.3390/ijms22073445] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 12/22/2022] Open
Abstract
Beckwith-Wiedemann syndrome (BWS) is a clinically and genetically heterogeneous overgrowth disease. BWS is caused by (epi)genetic defects at the 11p15 chromosomal region, which harbors two clusters of imprinted genes, IGF2/H19 and CDKN1C/KCNQ1OT1, regulated by differential methylation of imprinting control regions, H19/IGF2:IG DMR and KCNQ1OT1:TSS DMR, respectively. A subset of BWS patients show multi-locus imprinting disturbances (MLID), with methylation defects extended to other imprinted genes in addition to the disease-specific locus. Specific (epi)genotype-phenotype correlations have been defined in order to help clinicians in the classification of patients and referring them to a timely diagnosis and a tailored follow-up. However, specific phenotypic correlations have not been identified among MLID patients, thus causing a debate on the usefulness of multi-locus testing in clinical diagnosis. Finally, the high incidence of BWS monozygotic twins with discordant phenotypes, the high frequency of BWS among babies conceived by assisted reproductive technologies, and the female prevalence among BWS-MLID cases provide new insights into the timing of imprint establishment during embryo development. In this review, we provide an overview on the clinical and molecular diagnosis of single- and multi-locus BWS in pre- and post-natal settings, and a comprehensive analysis of the literature in order to define possible (epi)genotype-phenotype correlations in MLID patients.
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10
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Eggermann T, Kraft F, Lausberg E, Ergezinger K, Kunstmann E. Paternal 132 bp deletion affecting KCNQ1OT1 in 11p15.5 is associated with growth retardation but does not affect imprinting. J Med Genet 2021; 58:173-176. [PMID: 32447323 DOI: 10.1136/jmedgenet-2020-106868] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/24/2020] [Accepted: 03/30/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND The chromosomal region 11p15.5 harbours two imprinting centres (H19/IGF2:IG-DMR/IC1, KCNQ1OT1:TSS-DMR/IC2). Molecular alterations of the IC2 are associated with Beckwith-Wiedemann syndrome (BWS), whereas only single patients with growth retardation and Silver-Russell syndrome (SRS) features have been reported. CNVs in 11p15.5 account for less than 1% of patients with BWS and SRS, and they mainly consist of duplications of both ICs either affecting the maternal (SRS) or the paternal (BWS) allele. However, this correlation does not apply to smaller CNVs, which are associated with diverse clinical outcomes. METHODS AND RESULTS We identified a family with a 132 bp deletion within the KCNQ1OT1 gene, associated with growth retardation in case of paternal transmission but a normal phenotype when maternally inherited. Comparison of molecular and clinical data with cases from the literature helped to delineate its functional relevance. CONCLUSION Microdeletions within the paternal IC2 affecting the KCNQ1OT1 gene have been described in only five families, and they all include the differentially methylated region KCNQ1OT1:TSS-DMR/IC2 and parts of the KCNQ1 gene. However, these deletions have different impacts on the expression of both genes and the cell-cycle inhibitor CDKN1C. They thereby cause different phenotypes. The 132 bp deletion is the smallest deletion in the IC2 reported so far. It does not affect the IC2 methylation in general and the coding sequence of the KCNQ1 gene. Thus, the deletion is only associated with a growth retardation phenotype when paternally transmitted but not with other clinical features in case of maternal inheritance as observed for larger deletions.
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Affiliation(s)
- Thomas Eggermann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Aachen, Nordrhein-Westfalen, Germany
| | - Florian Kraft
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Aachen, Nordrhein-Westfalen, Germany
| | - Eva Lausberg
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Aachen, Nordrhein-Westfalen, Germany
| | | | - Erdmute Kunstmann
- Institute of Human Genetics, University of Würzburg, Würzburg, Germany
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11
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Eggermann T, Begemann M, Pfeiffer L. Unusual deletion of the maternal 11p15 allele in Beckwith-Wiedemann syndrome with an impact on both imprinting domains. Clin Epigenetics 2021; 13:30. [PMID: 33541417 PMCID: PMC7863277 DOI: 10.1186/s13148-021-01020-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/25/2021] [Indexed: 11/10/2022] Open
Abstract
Background Whereas duplications in 11p15.5 covering both imprinting centers (ICs) and their subordinated genes account for up to 1% of Beckwith–Wiedemann and Silver–Russell syndrome patients (BWS, SRS), the deletions in 11p15.5 reported so far only affect one of the ICs. In these cases, not only the size and gene content had an impact on the phenotype, but also the sex of the contributing parent influences the clinical signs of the deletion carrier. Results We here report on the first case with a heterozygous deletion within the maternal allele affecting genes which are regulated by both ICs in 11p15.5 in a BWS patient, and describe the molecular and clinical consequences in case of its maternal or paternal inheritance. Conclusions The identification of a unique deletion affecting both 11p15.5 imprinting domains in a BWS patient illustrates the complexity of the regulation mechanisms in these key imprinting regions.
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Affiliation(s)
- Thomas Eggermann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.
| | - Matthias Begemann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Lutz Pfeiffer
- MVZ Medicover Humangenetik Berlin Lichtenberg, Berlin, Germany
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12
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A paternally inherited 1.4 kb deletion of the 11p15.5 imprinting center 2 is associated with a mild familial Silver-Russell syndrome phenotype. Eur J Hum Genet 2020; 29:447-454. [PMID: 33177595 DOI: 10.1038/s41431-020-00753-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 10/20/2020] [Indexed: 12/30/2022] Open
Abstract
The Silver-Russell syndrome (SRS) is a rare disorder characterized by heterogeneous clinical features, including growth retardation, typical facial dysmorphisms, and body asymmetry. Genetic alterations causative of SRS mostly affect imprinted genes located on chromosomes 7 or 11. Hypomethylation of the Imprinting Center 1 (IC1) of the chromosome 11p15.5 is the most common cause of SRS, while the Imprinting Center 2 (IC2) has been more rarely involved. Specifically, maternally inherited 11p15.5 deletions including the IC2 have been associated with the Beckwith-Wiedemann Syndrome (BWS), while paternal deletions with a variable spectrum of phenotypes. Here, we describe the case of a girl with a mild SRS phenotype associated with a paternally inherited 1.4 kb deletion of IC2. The father of the proband inherited the deletion from his mother and showed normal growth, while the paternal grandmother had the deletion on her paternal chromosome and exhibited short stature. Together with previous findings obtained in mouse and humans, our data support the notion that deletion of the paternal copy of IC2 can cause SRS.
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13
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Yatsenko SA, Aarabi M, Hu J, Surti U, Ortiz D, Madan-Khetarpal S, Saller DN, Bellissimo D, Rajkovic A. Copy number alterations involving 59 ACMG-recommended secondary findings genes. Clin Genet 2020; 98:577-588. [PMID: 33009833 DOI: 10.1111/cge.13852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/14/2020] [Accepted: 09/13/2020] [Indexed: 12/17/2022]
Abstract
In clinical exome/genome sequencing, the American College of Medical Genetics and Genomics (ACMG) recommends reporting of secondary findings unrelated to a patient's phenotype when pathogenic single-nucleotide variants (SNVs) are observed in one of 59 genes associated with a life-threatening, medically actionable condition. Little is known about the incidence and sensitivity of chromosomal microarray analysis (CMA) for detection of pathogenic copy number variants (CNVs) comprising medically-actionable genes. Clinical CMA has been performed on 8865 individuals referred for molecular cytogenetic testing. We retrospectively reviewed the CMA results to identify patients with CNVs comprising genes included in the 59-ACMG list of secondary findings. We evaluated the clinical significance of these CNVs in respect to pathogenicity, phenotypic manifestations, and heritability. We identified 23 patients (0.26%) with relevant CNV either deletions comprising the entire gene or intragenic alterations involving one or more secondary findings genes. A number of patients and/or their family members with pathogenic CNVs manifest or expected to develop an anticipated clinical phenotype and would benefit from preventive management similar to the patients with pathogenic SNVs. To improve patients' care standardization should apply to reporting of both sequencing and CNVs obtained via clinical genome-wide analysis, including chromosomal microarray and exome/genome sequencing.
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Affiliation(s)
- Svetlana A Yatsenko
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Magee-Womens Research Institute, Pittsburgh, Pennsylvania, USA.,Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Mahmoud Aarabi
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jie Hu
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Urvashi Surti
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Damara Ortiz
- Department of Medical Genetics, Childrens Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, USA
| | - Suneeta Madan-Khetarpal
- Department of Medical Genetics, Childrens Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania, USA
| | - Devereux N Saller
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Daniel Bellissimo
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Aleksandar Rajkovic
- Department of Pathology, University of California San Francisco, San Francisco, California, USA.,Department of Obstetrics, Gynecology and Reproductive Sciences, University of California San Francisco, San Francisco, California, USA
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14
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Long QT and Silver Russell syndrome: First case report in a 9-year-old girl. HeartRhythm Case Rep 2020; 6:591-595. [PMID: 32983873 PMCID: PMC7498520 DOI: 10.1016/j.hrcr.2020.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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15
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Eßinger C, Karch S, Moog U, Fekete G, Lengyel A, Pinti E, Eggermann T, Begemann M. Frequency of KCNQ1 variants causing loss of methylation of Imprinting Centre 2 in Beckwith-Wiedemann syndrome. Clin Epigenetics 2020; 12:63. [PMID: 32393365 PMCID: PMC7216698 DOI: 10.1186/s13148-020-00856-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/23/2020] [Indexed: 11/21/2022] Open
Abstract
Background Beckwith-Wiedemann syndrome (BWS) is an imprinting disorder caused by disturbances of the chromosomal region 11p15.5. The most frequent molecular finding in BWS is loss of methylation (LOM) of the Imprinting Centre 2 (IC2) region on the maternal allele, which is localised in intron 10 of the KCNQ1 gene. In rare cases, LOM of IC2 has been reported in families with KCNQ1 germline variants which additionally cause long-QT syndrome (LQTS). Thus, a functional link between disrupted KCNQ1 transcripts and altered IC2 methylation has been suggested, resulting in the co-occurrence of LQTS and BWS in case of maternal inheritance. Whereas these cases were identified by chance or in patients with abnormal electrocardiograms, a systematic screen for KCNQ1 variants in IC2 LOM carriers has not yet been performed. Results We analysed 52 BWS patients with IC2 LOM to determine the frequency of germline variants in KCNQ1 by MLPA and an amplicon-based next generation sequencing approach. We identified one patient with a splice site variant causing premature transcription termination of KCNQ1. Conclusions Our study strengthens the hypothesis that proper KCNQ1 transcription is required for the establishment of IC2 methylation, but that KCNQ1 variants cause IC2 LOM only in a small number of BWS patients.
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Affiliation(s)
- Carla Eßinger
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany
| | - Stephanie Karch
- University Children's Hospital, Heidelberg University, Heidelberg, Germany
| | - Ute Moog
- Institute of Human Genetics, Heidelberg University, Heidelberg, Germany
| | - György Fekete
- II. Department of Paediatrics, Semmelweis University, Budapest, Hungary
| | - Anna Lengyel
- II. Department of Paediatrics, Semmelweis University, Budapest, Hungary
| | - Eva Pinti
- II. Department of Paediatrics, Semmelweis University, Budapest, Hungary
| | - Thomas Eggermann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany.
| | - Matthias Begemann
- Institute of Human Genetics, Medical Faculty, RWTH Aachen University, Pauwelsstr. 30, 52074, Aachen, Germany
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16
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Zhang Y, Du W, Yang B. Long non-coding RNAs as new regulators of cardiac electrophysiology and arrhythmias: Molecular mechanisms, therapeutic implications and challenges. Pharmacol Ther 2019; 203:107389. [DOI: 10.1016/j.pharmthera.2019.06.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 06/27/2019] [Indexed: 12/21/2022]
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17
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Gazzin A, Carli D, Sirchia F, Molinatto C, Cardaropoli S, Palumbo G, Zampino G, Ferrero GB, Mussa A. Phenotype evolution and health issues of adults with Beckwith-Wiedemann syndrome. Am J Med Genet A 2019; 179:1691-1702. [PMID: 31339634 DOI: 10.1002/ajmg.a.61301] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/10/2019] [Accepted: 07/09/2019] [Indexed: 11/06/2022]
Abstract
BACKGROUND Beckwith-Wiedemann syndrome (BWS) phenotype usually mitigates with age and data on adulthood are limited. Our study aims at reporting phenotype evolution and health issues in adulthood. METHODS 34 patients (16 males), aged 18-58 years (mean 28.5) with BWS were enrolled. RESULTS 26 patients were molecularly confirmed, 5 tested negative, and 3 were not tested. Final tall stature was present in 44%. Four patients developed Wilms' Tumor (2, 3, 5, and 10 years, respectively); one hepatoblastoma (22 years); one acute lymphoblastic leukemia (21 years); one adrenal adenoma and testicular Sertoli cell tumor (22 and 24 years, respectively); and three benign tumors (hepatic haemangioma, uterine myoma, and mammary fibroepithelioma). Surgery for BWS-related features was required in 85%. Despite surgical correction several patients presented morbidity and sequelae of BWS pediatric issues: pronunciation/swallow difficulties (n = 9) due to macroglossia, painful scoliosis (n = 4) consistent with lateralized overgrowth, recurrent urolithiasis (n = 4), azoospermia (n = 4) likely consequent to cryptorchidism, severe intellectual disability (n = 2) likely related to neonatal asphyxia and diabetes mellitus (n = 1) due to subtotal pancreatectomy for intractable hyperinsulinism. Four patients (two males) had healthy children (three physiologically conceived and one through assisted reproductive technology). CONCLUSIONS Adult health conditions in BWS are mostly consequent to pediatric issues, underlying the preventive role of follow-up strategies in childhood. Malignancy rate observed in early adulthood in this small cohort matches that observed in the first decade of life, cumulatively raising tumor rate in BWS to 20% during the observation period. Further studies are warranted in this direction.
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Affiliation(s)
- Andrea Gazzin
- Department of Public Health and Pediatrics, University of Torino, Torino, Italy
| | - Diana Carli
- Department of Public Health and Pediatrics, University of Torino, Torino, Italy
| | - Fabio Sirchia
- Institute for Maternal Child Health IRCCS "Burlo Garofolo", Trieste, Italy
| | - Cristina Molinatto
- Department of Public Health and Pediatrics, University of Torino, Torino, Italy
| | - Simona Cardaropoli
- Department of Public Health and Pediatrics, University of Torino, Torino, Italy
| | | | - Giuseppe Zampino
- Department of Woman and Child Health, Center for Rare Diseases and Birth Defects, Institute of Pediatrics, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | | | - Alessandro Mussa
- Department of Public Health and Pediatrics, University of Torino, Torino, Italy
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18
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Beygo J, Bürger J, Strom TM, Kaya S, Buiting K. Disruption of KCNQ1 prevents methylation of the ICR2 and supports the hypothesis that its transcription is necessary for imprint establishment. Eur J Hum Genet 2019; 27:903-908. [PMID: 30778172 DOI: 10.1038/s41431-019-0365-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/07/2019] [Accepted: 02/02/2019] [Indexed: 11/09/2022] Open
Abstract
Beckwith-Wiedemann syndrome (BWS; OMIM #130650) is an imprinting disorder caused by genetic or epigenetic alterations of one or both imprinting control regions on chromosome 11p15.5. Hypomethylation of the centromeric imprinting control region (KCNQ1OT1:TSS-DMR, ICR2) is the most common molecular cause of BWS and is present in about half of the cases. Based on a BWS family with a maternal deletion of the 5' part of KCNQ1 we have recently hypothesised that transcription of KCNQ1 is a prerequisite for the establishment of methylation at the KCNQ1OT1:TSS-DMR in the oocyte. Further evidence for this hypothesis came from a mouse model where methylation failed to be established when a poly(A) truncation cassette was inserted into this locus to prevent transcription through the DMR. Here we report on a family where a balanced translocation disrupts the KCNQ1 gene in intron 9. Maternal inheritance of this translocation is associated with hypomethylation of the KCNQ1OT1:TSS-DMR and BWS. This finding strongly supports our previous hypothesis that transcription of KCNQ1 is required for establishing the maternal methylation imprint at the KCNQ1OT1:TSS-DMR.
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Affiliation(s)
- Jasmin Beygo
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany.
| | | | - Tim M Strom
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Sabine Kaya
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Karin Buiting
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
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19
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Transcription alterations of KCNQ1 associated with imprinted methylation defects in the Beckwith-Wiedemann locus. Genet Med 2019; 21:1808-1820. [PMID: 30635621 PMCID: PMC6687501 DOI: 10.1038/s41436-018-0416-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/10/2018] [Indexed: 11/18/2022] Open
Abstract
Purpose Beckwith–Wiedemann syndrome (BWS) is a developmental disorder caused by dysregulation of the imprinted gene cluster of chromosome 11p15.5 and often associated with loss of methylation (LOM) of the imprinting center 2 (IC2) located in KCNQ1 intron 10. To unravel the etiological mechanisms underlying these epimutations, we searched for genetic variants associated with IC2 LOM. Methods We looked for cases showing the clinical features of both BWS and long QT syndrome (LQTS), which is often associated with KCNQ1 variants. Pathogenic variants were identified by genomic analysis and targeted sequencing. Functional experiments were performed to link these pathogenic variants to the imprinting defect. Results We found three rare cases in which complete IC2 LOM is associated with maternal transmission of KCNQ1 variants, two of which were demonstrated to affect KCNQ1 transcription upstream of IC2. As a consequence of KCNQ1 haploinsufficiency, these variants also cause LQTS on both maternal and paternal transmission. Conclusion These results are consistent with the hypothesis that, similar to what has been demonstrated in mouse, lack of transcription across IC2 results in failure of methylation establishment in the female germline and BWS later in development, and also suggest a new link between LQTS and BWS that is important for genetic counseling.
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20
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Wang KH, Kupa J, Duffy KA, Kalish JM. Diagnosis and Management of Beckwith-Wiedemann Syndrome. Front Pediatr 2019; 7:562. [PMID: 32039119 PMCID: PMC6990127 DOI: 10.3389/fped.2019.00562] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 12/23/2019] [Indexed: 01/10/2023] Open
Abstract
Beckwith-Wiedemann syndrome (BWS) is a human genomic imprinting disorder that presents with a wide spectrum of clinical features including overgrowth, abdominal wall defects, macroglossia, neonatal hypoglycemia, and predisposition to embryonal tumors. It is associated with genetic and epigenetic changes on the chromosome 11p15 region, which includes two imprinting control regions. Here we review strategies for diagnosing and managing BWS and delineate commonly used genetic tests to establish a molecular diagnosis of BWS. Recommended first-line testing assesses DNA methylation and copy number variation of the BWS region. Tissue mosaicism can occur in patients with BWS, posing a challenge for genetic testing, and a negative test result does not exclude a diagnosis of BWS. Further testing should analyze additional tissue samples or employ techniques with higher diagnostic yield. Identifying the BWS molecular subtype is valuable for coordinating patient care because of the (epi)genotype-phenotype correlations, including different risks and types of embryonal tumors.
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Affiliation(s)
- Kathleen H Wang
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Jonida Kupa
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Kelly A Duffy
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Jennifer M Kalish
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA, United States.,Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.,Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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21
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Marques P, Korbonits M. Pseudoacromegaly. Front Neuroendocrinol 2019; 52:113-143. [PMID: 30448536 DOI: 10.1016/j.yfrne.2018.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/30/2018] [Accepted: 11/14/2018] [Indexed: 01/19/2023]
Abstract
Individuals with acromegaloid physical appearance or tall stature may be referred to endocrinologists to exclude growth hormone (GH) excess. While some of these subjects could be healthy individuals with normal variants of growth or physical traits, others will have acromegaly or pituitary gigantism, which are, in general, straightforward diagnoses upon assessment of the GH/IGF-1 axis. However, some patients with physical features resembling acromegaly - usually affecting the face and extremities -, or gigantism - accelerated growth/tall stature - will have no abnormalities in the GH axis. This scenario is termed pseudoacromegaly, and its correct diagnosis can be challenging due to the rarity and variability of these conditions, as well as due to significant overlap in their characteristics. In this review we aim to provide a comprehensive overview of pseudoacromegaly conditions, highlighting their similarities and differences with acromegaly and pituitary gigantism, to aid physicians with the diagnosis of patients with pseudoacromegaly.
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Affiliation(s)
- Pedro Marques
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Márta Korbonits
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
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22
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Genetic and Epigenetic Control of CDKN1C Expression: Importance in Cell Commitment and Differentiation, Tissue Homeostasis and Human Diseases. Int J Mol Sci 2018; 19:ijms19041055. [PMID: 29614816 PMCID: PMC5979523 DOI: 10.3390/ijms19041055] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 03/31/2018] [Accepted: 03/31/2018] [Indexed: 12/28/2022] Open
Abstract
The CDKN1C gene encodes the p57Kip2 protein which has been identified as the third member of the CIP/Kip family, also including p27Kip1 and p21Cip1. In analogy with these proteins, p57Kip2 is able to bind tightly and inhibit cyclin/cyclin-dependent kinase complexes and, in turn, modulate cell division cycle progression. For a long time, the main function of p57Kip2 has been associated only to correct embryogenesis, since CDKN1C-ablated mice are not vital. Accordingly, it has been demonstrated that CDKN1C alterations cause three human hereditary syndromes, characterized by altered growth rate. Subsequently, the p57Kip2 role in several cell phenotypes has been clearly assessed as well as its down-regulation in human cancers. CDKN1C lies in a genetic locus, 11p15.5, characterized by a remarkable regional imprinting that results in the transcription of only the maternal allele. The control of CDKN1C transcription is also linked to additional mechanisms, including DNA methylation and specific histone methylation/acetylation. Finally, long non-coding RNAs and miRNAs appear to play important roles in controlling p57Kip2 levels. This review mostly represents an appraisal of the available data regarding the control of CDKN1C gene expression. In addition, the structure and function of p57Kip2 protein are briefly described and correlated to human physiology and diseases.
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Brioude F, Kalish JM, Mussa A, Foster AC, Bliek J, Ferrero GB, Boonen SE, Cole T, Baker R, Bertoletti M, Cocchi G, Coze C, De Pellegrin M, Hussain K, Ibrahim A, Kilby MD, Krajewska-Walasek M, Kratz CP, Ladusans EJ, Lapunzina P, Le Bouc Y, Maas SM, Macdonald F, Õunap K, Peruzzi L, Rossignol S, Russo S, Shipster C, Skórka A, Tatton-Brown K, Tenorio J, Tortora C, Grønskov K, Netchine I, Hennekam RC, Prawitt D, Tümer Z, Eggermann T, Mackay DJG, Riccio A, Maher ER. Expert consensus document: Clinical and molecular diagnosis, screening and management of Beckwith-Wiedemann syndrome: an international consensus statement. Nat Rev Endocrinol 2018; 14:229-249. [PMID: 29377879 PMCID: PMC6022848 DOI: 10.1038/nrendo.2017.166] [Citation(s) in RCA: 314] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Beckwith-Wiedemann syndrome (BWS), a human genomic imprinting disorder, is characterized by phenotypic variability that might include overgrowth, macroglossia, abdominal wall defects, neonatal hypoglycaemia, lateralized overgrowth and predisposition to embryonal tumours. Delineation of the molecular defects within the imprinted 11p15.5 region can predict familial recurrence risks and the risk (and type) of embryonal tumour. Despite recent advances in knowledge, there is marked heterogeneity in clinical diagnostic criteria and care. As detailed in this Consensus Statement, an international consensus group agreed upon 72 recommendations for the clinical and molecular diagnosis and management of BWS, including comprehensive protocols for the molecular investigation, care and treatment of patients from the prenatal period to adulthood. The consensus recommendations apply to patients with Beckwith-Wiedemann spectrum (BWSp), covering classical BWS without a molecular diagnosis and BWS-related phenotypes with an 11p15.5 molecular anomaly. Although the consensus group recommends a tumour surveillance programme targeted by molecular subgroups, surveillance might differ according to the local health-care system (for example, in the United States), and the results of targeted and universal surveillance should be evaluated prospectively. International collaboration, including a prospective audit of the results of implementing these consensus recommendations, is required to expand the evidence base for the design of optimum care pathways.
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Affiliation(s)
- Frédéric Brioude
- Sorbonne Université, Pierre and Marie Curie-Paris VI University (UPMC) Université Paris 06, INSERM UMR_S938 Centre de Recherche Saint-Antoine (CRSA), APHP Hôpital Trousseau, Explorations Fonctionnelles Endocriniennes, 26 Avenue du Docteur Arnold Netter, F-75012 Paris, France
| | - Jennifer M Kalish
- Division of Human Genetics, Children's Hospital of Philadelphia and the Department of Pediatrics at the Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alessandro Mussa
- Department of Public Health and Pediatric Sciences, University of Torino, Piazza Polonia 94, 10126 Torino, Italy
- Neonatal Intensive Care Unit, Department of Gynaecology and Obstetrics, Sant'Anna Hospital, Città della Salute e della Scienza di Torino, Corso Spezia 60, 10126 Torino, Italy
| | - Alison C Foster
- Birmingham Health Partners, West Midlands Regional Genetics Service, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham B15 2TG, UK
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Jet Bliek
- Department of Clinical Genetics, Academic Medical Center, University of Amsterdam, PO Box 7057 1007 MB Amsterdam, The Netherlands
| | - Giovanni Battista Ferrero
- Department of Public Health and Pediatric Sciences, University of Torino, Piazza Polonia 94, 10126 Torino, Italy
| | - Susanne E Boonen
- Clinical Genetic Unit, Department of Pediatrics, Zealand University Hospital, Sygehusvej 10 4000 Roskilde, Denmark
| | - Trevor Cole
- Birmingham Health Partners, West Midlands Regional Genetics Service, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham B15 2TG, UK
| | - Robert Baker
- Beckwith-Wiedemann Support Group UK, The Drum and Monkey, Wonston, Hazelbury Bryan, Sturminster Newton, Dorset DT10 2EE, UK
| | - Monica Bertoletti
- Italian Association of Beckwith-Wiedemann syndrome (AIBWS) Piazza Turati, 3, 21029, Vergiate (VA), Italy
| | - Guido Cocchi
- Alma Mater Studiorum, Bologna University, Paediatric Department, Neonatology Unit, Via Massarenti 11, 40138 Bologna BO, Italy
| | - Carole Coze
- Aix-Marseille Univ et Assistance Publique Hôpitaux de Marseille (APHM), Hôpital d'Enfants de La Timone, Service d'Hématologie-Oncologie Pédiatrique, 264 Rue Saint Pierre, 13385 Marseille, France
| | - Maurizio De Pellegrin
- Pediatric Orthopaedic Unit IRCCS Ospedale San Raffaele, Milan, Via Olgettina Milano, 60, 20132 Milano MI, Italy
| | - Khalid Hussain
- Department of Paediatric Medicine, Division of Endocrinology, Sidra Medical and Research Center, Al Gharrafa Street, Ar-Rayyan, Doha, Qatar
| | - Abdulla Ibrahim
- Department of Plastic and Reconstructive Surgery, North Bristol National Health Service (NHS) Trust, Southmead Hospital, Bristol BS10 5NB, UK
| | - Mark D Kilby
- Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- Fetal Medicine Centre, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Edgbaston, Birmingham, B15 2TG, UK
| | | | - Christian P Kratz
- Pediatric Hematology and Oncology, Hannover Medical School, Carl-Neuberg-Strasse 1 30625, Hannover, Germany
| | - Edmund J Ladusans
- Department of Paediatric Cardiology, Royal Manchester Children's Hospital, Manchester, M13 8WL UK
| | - Pablo Lapunzina
- Instituto de Genética Médica y Molecular (INGEMM)-IdiPAZ, Hospital Universitario La Paz-UAM Paseo de La Castellana, 261, 28046, Madrid, Spain
- CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, Calle de Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Yves Le Bouc
- Sorbonne Université, Pierre and Marie Curie-Paris VI University (UPMC) Université Paris 06, INSERM UMR_S938 Centre de Recherche Saint-Antoine (CRSA), APHP Hôpital Trousseau, Explorations Fonctionnelles Endocriniennes, 26 Avenue du Docteur Arnold Netter, F-75012 Paris, France
| | - Saskia M Maas
- Department of Clinical Genetics, Academic Medical Center, University of Amsterdam, PO Box 7057 1007 MB Amsterdam, The Netherlands
| | - Fiona Macdonald
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's National Health Service (NHS) Foundation Trust, Birmingham, B15 2TG UK
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital and Department of Clinical Genetics, Institute of Clinical Medicine, University of Tartu, L. Puusepa 2, 51014, Tartu, Estonia
| | - Licia Peruzzi
- European Society for Paediatric Nephrology (ESPN), Inherited Kidney Disorders Working Group
- AOU Città della Salute e della Scienza di Torino, Regina Margherita Children's Hospital, Turin, Italy
| | - Sylvie Rossignol
- Service de Pédiatrie, Hôpitaux Universitaires de Strasbourg, Laboratoire de Génétique Médicale, INSERM U1112 Avenue Molière 67098 STRASBOURG Cedex, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, 4 Rue Kirschleger, 67000 Strasbourg, France
| | - Silvia Russo
- Medical Cytogenetics and Molecular Genetics Laboratory, Centro di Ricerche e Tecnologie Biomediche IRCCS, Istituto Auxologico Italiano, Via Zucchi 18, 20095 Cusano, Milan, Italy
| | - Caroleen Shipster
- Great Ormond Street Hospital for Children National Health Service (NHS) Foundation Trust, London, WC1N 3JH, UK
| | - Agata Skórka
- Department of Medical Genetics, The Children's Memorial Health Institute, 20, 04-730, Warsaw, Poland
- Department of Pediatrics, The Medical University of Warsaw, Zwirki i Wigury 63a, 02-091 Warszawa, Poland
| | - Katrina Tatton-Brown
- South West Thames Regional Genetics Service and St George's University of London and Institute of Cancer Research, London, SW17 0RE, UK
| | - Jair Tenorio
- Instituto de Genética Médica y Molecular (INGEMM)-IdiPAZ, Hospital Universitario La Paz-UAM Paseo de La Castellana, 261, 28046, Madrid, Spain
- CIBERER, Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII, Calle de Melchor Fernández Almagro, 3, 28029, Madrid, Spain
| | - Chiara Tortora
- Regional Center for CLP, Smile House, San Paolo University Hospital, Via Antonio di Rudinì, 8, 20142, Milan, Italy
| | - Karen Grønskov
- Kennedy Center, Department of Clinical Genetics, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Irène Netchine
- Sorbonne Université, Pierre and Marie Curie-Paris VI University (UPMC) Université Paris 06, INSERM UMR_S938 Centre de Recherche Saint-Antoine (CRSA), APHP Hôpital Trousseau, Explorations Fonctionnelles Endocriniennes, 26 Avenue du Docteur Arnold Netter, F-75012 Paris, France
| | - Raoul C Hennekam
- Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam-Zuidoost, Amsterdam, The Netherlands
| | - Dirk Prawitt
- Center for Pediatrics and Adolescent Medicine, Johannes Gutenberg University Medical Center, Langenbeckstr. 1, D-55101, Mainz, Germany
| | - Zeynep Tümer
- Kennedy Center, Department of Clinical Genetics, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Thomas Eggermann
- Institute of Human Genetics, University Hospital, Technical University of Aachen, Templergraben 55, 52062, Aachen, Germany
| | - Deborah J G Mackay
- Human Development and Health, Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, UK
| | - Andrea Riccio
- Department of Environmental, Biological, and Pharmaceutical Sciences and Technologies (DiSTABiF), University of Campania Luigi Vanvitelli, Caserta and Institute of Genetics and Biophysics "A. Buzzati-Traverso" - CNR, Via Pietro Castellino, 111,80131, Naples, Italy
| | - Eamonn R Maher
- Department of Medical Genetics, University of Cambridge and National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre and Cancer Research UK Cambridge Centre, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK
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24
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Coto E, Calvo D, Reguero JR, Morís C, Rubín JM, Díaz-Corte C, Gil-Peña H, Alosno B, Iglesias S, Gómez J. Differential methylation of lncRNA KCNQ1OT1 promoter polymorphism was associated with symptomatic cardiac long QT. Epigenomics 2017; 9:1049-1057. [PMID: 28749187 DOI: 10.2217/epi-2017-0024] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM To investigate whether the differential methylation of KCNQ1OT1 was associated with the risk of symptomatic long QTc. PATIENTS & METHODS We investigated the methylation status of KCNQ1OT1 in a cohort of patients (n = 131) with a symptomatic prolonged QTc. All the patients were genotyped for a common promoter polymorphism (rs11023840). They were also genotyped for DNA digested with the methylation-sensitive HpaII restriction enzyme. RESULTS We found a significant higher frequency of AA genotype (p = 0.02) in the patients compared with healthy controls (n = 240). In the HpaII-digested samples there was a higher frequency of the A-allele among the patients compared with the controls (p = 0.02). CONCLUSION Our findings supported a role for the differential methylation/imprinting of KCNQ1OT1 in the risk for symptomatic prolonged QTc.
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Affiliation(s)
- Eliecer Coto
- Genética Molecular, Hospital Universitario Central Asturias, Oviedo, Spain.,Departamento Medicina, Universidad de Oviedo, Oviedo, Spain
| | - David Calvo
- Cardiología-Fundación ASTURCOR, Hospital Universitario Central Asturias, Oviedo, Spain
| | - Julián R Reguero
- Cardiología-Fundación ASTURCOR, Hospital Universitario Central Asturias, Oviedo, Spain
| | - César Morís
- Cardiología-Fundación ASTURCOR, Hospital Universitario Central Asturias, Oviedo, Spain.,Departamento Medicina, Universidad de Oviedo, Oviedo, Spain
| | - Jose M Rubín
- Cardiología-Fundación ASTURCOR, Hospital Universitario Central Asturias, Oviedo, Spain
| | | | - Helena Gil-Peña
- Pediatría, Hospital Universitario Central Asturias, Oviedo, Spain
| | - Belén Alosno
- Genética Molecular, Hospital Universitario Central Asturias, Oviedo, Spain
| | - Sara Iglesias
- Genética Molecular, Hospital Universitario Central Asturias, Oviedo, Spain
| | - Juan Gómez
- Genética Molecular, Hospital Universitario Central Asturias, Oviedo, Spain
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25
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Cytrynbaum C, Chong K, Hannig V, Choufani S, Shuman C, Steele L, Morgan T, Scherer SW, Stavropoulos DJ, Basran RK, Weksberg R. Genomic imbalance in the centromeric 11p15 imprinting center in three families: Further evidence of a role for IC2 as a cause of Russell-Silver syndrome. Am J Med Genet A 2016; 170:2731-9. [PMID: 27374371 DOI: 10.1002/ajmg.a.37819] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 06/15/2016] [Indexed: 11/07/2022]
Abstract
Russell-Silver syndrome is a heterogeneous disorder characterized by intrauterine growth retardation, postnatal growth deficiency, characteristic facial appearance, and other variable features. Genetic and epigenetic alterations are identified in about 60% of individuals with Russell-Silver syndrome. Most frequently, Russell-Silver syndrome is caused by altered gene expression on chromosome 11p15 due to loss of methylation at the telomeric imprinting center. To date there have been a handful of isolated clinical reports implicating the centromeric imprinting center 2 in the etiology of Russell-Silver syndrome. Here we report three new families with genomic imbalances, involving imprinting center 2 resulting in gain of methylation at this center and a Russell-Silver syndrome phenotype, including two families with a maternally inherited microduplication and the first pediatric patient with a paternally derived microdeletion. The findings in our families provide additional evidence of a role for imprinting center 2 in the etiology of Russell-Silver syndrome and suggest that imprinting center 2 imprinting abnormalities may be a more common cause of Russell-Silver syndrome than previously recognized. Furthermore, our findings together with previous clinical reports of genomic imbalances involving imprinting center 2 serve to underscore the complexity of the epigenetic regulation of the 11p15 region making it challenging to predict phenotype on the basis of genotype alone. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Cheryl Cytrynbaum
- Division of Clinical & Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada.,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Karen Chong
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.,Prenatal Diagnosis and Medical Genetics Program, Mount Sinai Hospital, Toronto, Ontario, Canada.,Department of Pediatrics and Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Vickie Hannig
- Division of Genetics and Genomic Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Sanaa Choufani
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Cheryl Shuman
- Division of Clinical & Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada.,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leslie Steele
- Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Thomas Morgan
- Division of Genetics and Genomic Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Stephen W Scherer
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.,The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Ontario, Canada.,McLaughlin Centre for Molecular Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Dimitri J Stavropoulos
- Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.,Paediatric Laboratory Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Raveen K Basran
- Paediatric Laboratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.,Paediatric Laboratory Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Rosanna Weksberg
- Division of Clinical & Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada. .,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada. .,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada. .,Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.
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26
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Beygo J, Joksic I, Strom TM, Lüdecke HJ, Kolarova J, Siebert R, Mikovic Z, Horsthemke B, Buiting K. A maternal deletion upstream of the imprint control region 2 in 11p15 causes loss of methylation and familial Beckwith-Wiedemann syndrome. Eur J Hum Genet 2016; 24:1280-6. [PMID: 26839037 DOI: 10.1038/ejhg.2016.3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/15/2015] [Accepted: 12/22/2015] [Indexed: 11/09/2022] Open
Abstract
Beckwith-Wiedemann syndrome (BWS; OMIM #130650) is an overgrowth syndrome caused by different genetic or epigenetic alterations affecting imprinted regions on chromosome 11p15.5. Here we report a family with multiple offspring affected with BWS including giant omphalocoeles in which maternal transmission of a chromosomal rearrangement including an inversion and two deletions leads to hypomethylation of the imprint control region 2 (ICR2). As the deletion includes the promoter and 5' part of the KCNQ1 gene, we suggest that transcription of this gene may be involved in establishing the maternal methylation imprint of the ICR2, which is located in intron 10 of KCNQ1.
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Affiliation(s)
- Jasmin Beygo
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Ivana Joksic
- Clinic of Gynecology and Obstetrics Narodni front, Belgrade, Serbia
| | - Tim M Strom
- Institut für Humangenetik, Technische Universität München, München, Germany
| | - Hermann-Josef Lüdecke
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Julia Kolarova
- Institut für Humangenetik, Christian-Albrechts-Universität Kiel and Universitätsklinikum Schleswig-Holstein, Campus Kiel, Germany
| | - Reiner Siebert
- Institut für Humangenetik, Christian-Albrechts-Universität Kiel and Universitätsklinikum Schleswig-Holstein, Campus Kiel, Germany
| | - Zeljko Mikovic
- Clinic of Gynecology and Obstetrics Narodni front, Belgrade, Serbia
| | - Bernhard Horsthemke
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
| | - Karin Buiting
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen, Essen, Germany
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27
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Mussa A, Di Candia S, Russo S, Catania S, De Pellegrin M, Di Luzio L, Ferrari M, Tortora C, Meazzini MC, Brusati R, Milani D, Zampino G, Montirosso R, Riccio A, Selicorni A, Cocchi G, Ferrero GB. Recommendations of the Scientific Committee of the Italian Beckwith-Wiedemann Syndrome Association on the diagnosis, management and follow-up of the syndrome. Eur J Med Genet 2015; 59:52-64. [PMID: 26592461 DOI: 10.1016/j.ejmg.2015.11.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 11/03/2015] [Accepted: 11/17/2015] [Indexed: 01/10/2023]
Abstract
UNLABELLED Beckwith-Wiedemann syndrome (BWS) is the most common (epi)genetic overgrowth-cancer predisposition disorder. Given the absence of consensual recommendations or international guidelines, the Scientific Committee of the Italian BWS Association (www.aibws.org) proposed these recommendations for the diagnosis, molecular testing, clinical management, follow-up and tumor surveillance of patients with BWS. The recommendations are intended to allow a timely and appropriate diagnosis of the disorder, to assist patients and their families, to provide clinicians and caregivers optimal strategies for an adequate and satisfactory care, aiming also at standardizing clinical practice as a national uniform approach. They also highlight the direction of future research studies in this setting. With recent advances in understanding the disease (epi)genetic mechanisms and in describing large cohorts of BWS patients, the natural history of the disease will be dissected. In the era of personalized medicine, the emergence of specific (epi)genotype-phenotype correlations in BWS will likely lead to differentiated follow-up approaches for the molecular subgroups, to the development of novel tools to evaluate the likelihood of cancer development and to the refinement and optimization of current tumor screening strategies. CONCLUSIONS In this article, we provide the first comprehensive recommendations on the complex management of patients with Beckwith-Wiedemann syndrome.
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Affiliation(s)
- Alessandro Mussa
- Department of Public Health and Pediatric Sciences, University of Torino, Torino, Italy.
| | - Stefania Di Candia
- Department of Pediatrics, San Raffaele Scientific Institute, Milan, Italy
| | - Silvia Russo
- Laboratory of Cytogenetics and Molecular Genetics, Istituto Auxologico Italiano, Milan, Italy
| | - Serena Catania
- Pediatric Oncology Unit, Department of Hematology and Pediatric Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | | | - Luisa Di Luzio
- Obstetrics and Gynecology Unit, Niguarda Hospital, Milan, Italy
| | - Mario Ferrari
- Regional Center for CLP, Smile-House, San Paolo University Hospital, Milan, Italy
| | - Chiara Tortora
- Regional Center for CLP, Smile-House, San Paolo University Hospital, Milan, Italy
| | | | - Roberto Brusati
- Regional Center for CLP, Smile-House, San Paolo University Hospital, Milan, Italy
| | - Donatella Milani
- Pediatric Highly Intensive Care Unit, Department of Pathophysiology and Transplantation, Università degli Studi di Milano Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Giuseppe Zampino
- Center for Rare Diseases, Department of Pediatrics, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Rosario Montirosso
- 0-3 Center for the Study of Social Emotional Development of the at Risk Infant, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Andrea Riccio
- DiSTABiF, Second University of Naples and Institute of Genetics and Biophysics "A. Buzzati-Traverso" - CNR, Naples, Italy
| | - Angelo Selicorni
- Clinical Pediatric Genetics Unit, Pediatrics Clinics, MBBM Foundation, S. Gerardo Hospital, Monza, Italy
| | - Guido Cocchi
- GC Department of Pediatrics, Alma Mater Studiorum, University of Bologna, Bologna, Italy
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28
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Mussa A, Russo S, Larizza L, Riccio A, Ferrero GB. (Epi)genotype-phenotype correlations in Beckwith-Wiedemann syndrome: a paradigm for genomic medicine. Clin Genet 2015; 89:403-415. [PMID: 26138266 DOI: 10.1111/cge.12635] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/24/2015] [Accepted: 06/30/2015] [Indexed: 12/23/2022]
Abstract
Beckwith-Wiedemann syndrome (BWS) is the commonest overgrowth cancer predisposition disorder and represents a model for human imprinting dysregulation and tumorigenesis. BWS features can variably combine and present a widely variable range of severity in the phenotypic expression. This wide spectrum is paralleled at molecular level by complex (epi)genetic defects on chromosome 11p15.5 leading to disrupted expression of imprinted genes controlling growth and cellular proliferation. In this review, we outline the spectrum of clinical manifestations of BWS analyzing their (epi)genotype-phenotype correlations. The differences observed in the phenotypic profiles of BWS molecular subtypes allow a composite view of this syndrome with implications on clinical care, diagnosis, follow-up, and management, and provide directions for future disease monitoring.
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Affiliation(s)
- A Mussa
- Department of Pediatrics and Public Health Sciences, University of Torino, Torino, Italy
| | - S Russo
- Laboratory of Cytogenetics and Molecular Genetics, Istituto Auxologico Italiano, Milan, Italy
| | - L Larizza
- Laboratory of Cytogenetics and Molecular Genetics, Istituto Auxologico Italiano, Milan, Italy.,Department of Health Sciences, University of Milan, Milan, Italy
| | - A Riccio
- DiSTABiF, Second University of Naples, Napoli, Italy.,Institute of Genetics and Biophysics "A. Buzzati-Traverso" - CNR, Naples, Italy
| | - G B Ferrero
- Department of Pediatrics and Public Health Sciences, University of Torino, Torino, Italy
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29
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A novel large deletion of the ICR1 region including H19 and putative enhancer elements. BMC MEDICAL GENETICS 2015; 16:30. [PMID: 25943194 PMCID: PMC4630834 DOI: 10.1186/s12881-015-0173-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 04/22/2015] [Indexed: 02/01/2023]
Abstract
Background Beckwith-Wiedemann syndrome (BWS) is a rare pediatric overgrowth disorder with a variable clinical phenotype caused by deregulation affecting imprinted genes in the chromosomal region 11p15. Alterations of the imprinting control region 1 (ICR1) at the IGF2/H19 locus resulting in biallelic expression of IGF2 and biallelic silencing of H19 account for approximately 10% of patients with BWS. The majority of these patients have epimutations of the ICR1 without detectable DNA sequence changes. Only a few patients were found to have deletions. Most of these deletions are small affecting different parts of the ICR1 differentially methylated region (ICR1-DMR) removing target sequences for CTCF. Only a very few deletions reported so far include the H19 gene in addition to the CTCF binding sites. None of these deletions include IGF2. Case presentation A male patient was born with hypotonia, facial dysmorphisms and hypoglycemia suggestive of Beckwith-Wiedemann syndrome. Using methylation-specific (MS)-MLPA (Multiplex ligation-dependent probe amplification) we have identified a maternally inherited large deletion of the ICR1 region in a patient and his mother. The deletion results in a variable clinical expression with a classical BWS in the mother and a more severe presentation of BWS in her son. By genome-wide SNP array analysis the deletion was found to span ~100 kb genomic DNA including the ICR1DMR, H19, two adjacent non-imprinted genes and two of three predicted enhancer elements downstream to H19. Methylation analysis by deep bisulfite next generation sequencing revealed hypermethylation of the maternal allele at the IGF2 locus in both, mother and child, although IGF2 is not affected by the deletion. Conclusions We here report on a novel large familial deletion of the ICR1 region in a BWS family. Due to the deletion of the ICR1-DMR CTCF binding cannot take place and the residual enhancer elements have access to the IGF2 promoters. The aberrant methylation (hypermethylation) of the maternal IGF2 allele in both affected family members may reflect the active state of the normally silenced maternal IGF2 copy and can be a consequence of the deletion. The deletion results in a variable clinical phenotype and expression. Electronic supplementary material The online version of this article (doi:10.1186/s12881-015-0173-2) contains supplementary material, which is available to authorized users.
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30
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Identification of Genetic Alterations, as Causative Genetic Defects in Long QT Syndrome, Using Next Generation Sequencing Technology. PLoS One 2014; 9:e114894. [PMID: 25494010 PMCID: PMC4262446 DOI: 10.1371/journal.pone.0114894] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 11/15/2014] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Long QT Syndrome is an inherited channelopathy leading to sudden cardiac death due to ventricular arrhythmias. Despite that several genes have been associated with the disease, nearly 20% of cases remain without an identified genetic cause. Other genetic alterations such as copy number variations have been recently related to Long QT Syndrome. Our aim was to take advantage of current genetic technologies in a family affected by Long QT Syndrome in order to identify the cause of the disease. METHODS Complete clinical evaluation was performed in all family members. In the index case, a Next Generation Sequencing custom-built panel, including 55 sudden cardiac death-related genes, was used both for detection of sequence and copy number variants. Next Generation Sequencing variants were confirmed by Sanger method. Copy number variations variants were confirmed by Multiplex Ligation dependent Probe Amplification method and at the mRNA level. Confirmed variants and copy number variations identified in the index case were also analyzed in relatives. RESULTS In the index case, Next Generation Sequencing revealed a novel variant in TTN and a large deletion in KCNQ1, involving exons 7 and 8. Both variants were confirmed by alternative techniques. The mother and the brother of the index case were also affected by Long QT Syndrome, and family cosegregation was observed for the KCNQ1 deletion, but not for the TTN variant. CONCLUSIONS Next Generation Sequencing technology allows a comprehensive genetic analysis of arrhythmogenic diseases. We report a copy number variation identified using Next Generation Sequencing analysis in Long QT Syndrome. Clinical and familiar correlation is crucial to elucidate the role of genetic variants identified to distinguish the pathogenic ones from genetic noise.
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Abstract
Ion channels are essential for basic cellular function and for processes including sensory perception and intercellular communication in multicellular organisms. Voltage-gated potassium (Kv) channels facilitate dynamic cellular repolarization during an action potential, opening in response to membrane depolarization to facilitate K+ efflux. In both excitable and nonexcitable cells other, constitutively active, K+ channels provide a relatively constant repolarizing force to control membrane potential, ion homeostasis, and secretory processes. Of the forty known human Kv channel pore-forming α subunits that coassemble in various combinations to form the fundamental tetrameric channel pore and voltage sensor module, KCNQ1 is unique. KCNQ1 stands alone in having the capacity to form either channels that are voltage-dependent and require membrane depolarization for activation, or constitutively active channels. In mammals, KCNQ1 regulates processes including gastric acid secretion, thyroid hormone biosynthesis, salt and glucose homeostasis, and cell volume and in some species is required for rhythmic beating of the heart. In this review, the author discusses the unique functional properties, regulation, cell biology, diverse physiological roles, and involvement in human disease states of this chameleonic K+ channel.
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Affiliation(s)
- Flavia Cerrato
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Agostina De Crescenzo
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Andrea Riccio
- 1] Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy [2] Institute of Genetics and Biophysics A.Buzzati-Traverso, CNR, Naples, Italy
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Tabolacci E, Chiurazzi P. Epigenetics, fragile X syndrome and transcriptional therapy. Am J Med Genet A 2013; 161A:2797-808. [PMID: 24123753 DOI: 10.1002/ajmg.a.36264] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 09/06/2013] [Indexed: 12/13/2022]
Abstract
Epigenetics refers to the study of heritable changes in gene expression that occur without a change in DNA sequence. Epigenetic mechanisms therefore include all transcriptional controls that determine how genes are expressed during development and differentiation, but also in individual cells responding to environmental stimuli. The purpose of this review is to examine the basic principles of epigenetic mechanisms and their contribution to human disorders with a particular focus on fragile X syndrome (FXS), the most common monogenic form of developmental cognitive impairment. FXS represents a prototype of the so-called repeat expansion disorders due to "dynamic" mutations, namely the expansion (known as "full mutation") of a CGG repeat in the 5'UTR of the FMR1 gene. This genetic anomaly is accompanied by epigenetic modifications (mainly DNA methylation and histone deacetylation), resulting in the inactivation of the FMR1 gene. The presence of an intact FMR1 coding sequence allowed pharmacological reactivation of gene transcription, particularly through the use of the DNA demethylating agent 5'-aza-2'-deoxycytydine and/or inhibitors of histone deacetylases. These treatments suggested that DNA methylation is dominant over histone acetylation in silencing the FMR1 gene. The importance of DNA methylation in repressing FMR1 transcription is confirmed by the existence of rare unaffected males carrying unmethylated full mutations. Finally, we address the potential use of epigenetic approaches to targeted treatment of other genetic conditions.
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