1
|
Wojcik MH, Poduri AH, Holm IA, MacRae CA, Goldstein RD. The fundamental need for unifying phenotypes in sudden unexpected pediatric deaths. Front Med (Lausanne) 2023; 10:1166188. [PMID: 37332751 PMCID: PMC10273404 DOI: 10.3389/fmed.2023.1166188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 05/03/2023] [Indexed: 06/20/2023] Open
Abstract
A definitive, authoritative approach to evaluate the causes of unexpected, and ultimately unexplained, pediatric deaths remains elusive, relegating final conclusions to diagnoses of exclusion in the vast majority of cases. Research into unexplained pediatric deaths has focused primarily on sudden infant deaths (under 1 year of age) and led to the identification of several potential, albeit incompletely understood, contributory factors: nonspecific pathology findings, associations with sleep position and environment that may not be uniformly relevant, and the elucidation of a role for serotonin that is practically difficult to estimate in any individual case. Any assessment of progress in this field must also acknowledge the failure of current approaches to substantially decrease mortality rates in decades. Furthermore, potential commonalities with pediatric deaths across a broader age spectrum have not been widely considered. Recent epilepsy-related observations and genetic findings, identified post-mortem in both infants and children who died suddenly and unexpectedly, suggest a role for more intense and specific phenotyping efforts as well as an expanded role for genetic and genomic evaluation. We therefore present a new approach to reframe the phenotype in sudden unexplained deaths in the pediatric age range, collapsing many distinctions based on arbitrary factors (such as age) that have previously guided research in this area, and discuss its implications for the future of postmortem investigation.
Collapse
Affiliation(s)
- Monica H. Wojcik
- Robert’s Program for Sudden Unexpected Death in Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Division of Newborn Medicine, Department of Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - Annapurna H. Poduri
- Robert’s Program for Sudden Unexpected Death in Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, United States
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital and Harvard Medical School, Boston, MA, United States
| | - Ingrid A. Holm
- Robert’s Program for Sudden Unexpected Death in Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
| | - Calum A. MacRae
- Harvard Medical School, Boston, MA, United States
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, United States
| | - Richard D. Goldstein
- Robert’s Program for Sudden Unexpected Death in Pediatrics, Boston Children’s Hospital, Boston, MA, United States
- Harvard Medical School, Boston, MA, United States
- Division of General Pediatrics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, United States
| |
Collapse
|
2
|
Daimi H, Lozano-Velasco E, Aranega A, Franco D. Genomic and Non-Genomic Regulatory Mechanisms of the Cardiac Sodium Channel in Cardiac Arrhythmias. Int J Mol Sci 2022; 23:1381. [PMID: 35163304 PMCID: PMC8835759 DOI: 10.3390/ijms23031381] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/30/2021] [Accepted: 01/06/2022] [Indexed: 12/19/2022] Open
Abstract
Nav1.5 is the predominant cardiac sodium channel subtype, encoded by the SCN5A gene, which is involved in the initiation and conduction of action potentials throughout the heart. Along its biosynthesis process, Nav1.5 undergoes strict genomic and non-genomic regulatory and quality control steps that allow only newly synthesized channels to reach their final membrane destination and carry out their electrophysiological role. These regulatory pathways are ensured by distinct interacting proteins that accompany the nascent Nav1.5 protein along with different subcellular organelles. Defects on a large number of these pathways have a tremendous impact on Nav1.5 functionality and are thus intimately linked to cardiac arrhythmias. In the present review, we provide current state-of-the-art information on the molecular events that regulate SCN5A/Nav1.5 and the cardiac channelopathies associated with defects in these pathways.
Collapse
Affiliation(s)
- Houria Daimi
- Biochemistry and Molecular Biology Laboratory, Faculty of Pharmacy, University of Monastir, Monastir 5000, Tunisia
| | - Estefanía Lozano-Velasco
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (E.L.-V.); (A.A.); (D.F.)
- Medina Foundation, Technology Park of Health Sciences, Av. del Conocimiento, 34, 18016 Granada, Spain
| | - Amelia Aranega
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (E.L.-V.); (A.A.); (D.F.)
- Medina Foundation, Technology Park of Health Sciences, Av. del Conocimiento, 34, 18016 Granada, Spain
| | - Diego Franco
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (E.L.-V.); (A.A.); (D.F.)
- Medina Foundation, Technology Park of Health Sciences, Av. del Conocimiento, 34, 18016 Granada, Spain
| |
Collapse
|
3
|
Wallace MJ, El Refaey M, Mesirca P, Hund TJ, Mangoni ME, Mohler PJ. Genetic Complexity of Sinoatrial Node Dysfunction. Front Genet 2021; 12:654925. [PMID: 33868385 PMCID: PMC8047474 DOI: 10.3389/fgene.2021.654925] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/01/2021] [Indexed: 12/13/2022] Open
Abstract
The pacemaker cells of the cardiac sinoatrial node (SAN) are essential for normal cardiac automaticity. Dysfunction in cardiac pacemaking results in human sinoatrial node dysfunction (SND). SND more generally occurs in the elderly population and is associated with impaired pacemaker function causing abnormal heart rhythm. Individuals with SND have a variety of symptoms including sinus bradycardia, sinus arrest, SAN block, bradycardia/tachycardia syndrome, and syncope. Importantly, individuals with SND report chronotropic incompetence in response to stress and/or exercise. SND may be genetic or secondary to systemic or cardiovascular conditions. Current management of patients with SND is limited to the relief of arrhythmia symptoms and pacemaker implantation if indicated. Lack of effective therapeutic measures that target the underlying causes of SND renders management of these patients challenging due to its progressive nature and has highlighted a critical need to improve our understanding of its underlying mechanistic basis of SND. This review focuses on current information on the genetics underlying SND, followed by future implications of this knowledge in the management of individuals with SND.
Collapse
Affiliation(s)
- Michael J. Wallace
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Mona El Refaey
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Pietro Mesirca
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Thomas J. Hund
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Matteo E. Mangoni
- CNRS, INSERM, Institut de Génomique Fonctionnelle, Université de Montpellier, Montpellier, France
- Laboratory of Excellence ICST, Montpellier, France
| | - Peter J. Mohler
- Frick Center for Heart Failure and Arrhythmia Research, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| |
Collapse
|
4
|
Rochtus AM, Goldstein RD, Holm IA, Brownstein CA, Pérez‐Palma E, Haynes R, Lal D, Poduri AH. The role of sodium channels in sudden unexpected death in pediatrics. Mol Genet Genomic Med 2020; 8:e1309. [PMID: 32449611 PMCID: PMC7434613 DOI: 10.1002/mgg3.1309] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/21/2020] [Accepted: 04/27/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Sudden Unexpected Death in Pediatrics (SUDP) is a tragic event, likely caused by the complex interaction of multiple factors. The presence of hippocampal abnormalities in many children with SUDP suggests that epilepsy-related mechanisms may contribute to death, similar to Sudden Unexplained Death in Epilepsy. Because of known associations between the genes SCN1A and SCN5A and sudden death, and shared mechanisms and patterns of expression in genes encoding many voltage-gated sodium channels (VGSCs), we hypothesized that individuals dying from SUDP have pathogenic variants across the entire family of cardiac arrhythmia- and epilepsy-associated VGSC genes. METHODS To address this hypothesis, we evaluated whole-exome sequencing data from infants and children with SUDP for variants in VGSC genes, reviewed the literature for all SUDP-associated variants in VGSCs, applied a novel paralog analysis to all variants, and evaluated all variants according to American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS In our cohort of 73 cases of SUDP, we assessed 11 variants as pathogenic in SCN1A, SCN1B, and SCN10A, genes with long-standing disease associations, and in SCN3A, SCN4A, and SCN9A, VGSC gene paralogs with more recent disease associations. From the literature, we identified 82 VGSC variants in SUDP cases. Pathogenic variants clustered at conserved amino acid sites intolerant to variation across the VGSC genes, which is unlikely to occur in the general population (p < .0001). For 54% of variants previously reported in literature, we identified conflicting evidence regarding pathogenicity when applying ACMG criteria and modern population data. CONCLUSION We report variants in several VGSC genes in cases with SUDP, involving both arrhythmia- and epilepsy-associated genes. Accurate variant assessment as well as future studies are essential for an improved understanding of the contribution of sodium channel-related variants to SUDP.
Collapse
Affiliation(s)
- Anne M. Rochtus
- Department of NeurologyBoston Children's Hospital and Harvard Medical SchoolBostonMAUSA
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Department of PediatricsUniversity of LeuvenLeuvenBelgium
| | - Richard D. Goldstein
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Department of PediatricsBoston Children’s Hospital and Harvard Medical SchoolBostonMAUSA
| | - Ingrid A. Holm
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Department of PediatricsBoston Children’s Hospital and Harvard Medical SchoolBostonMAUSA
- Department of MedicineDivision of Genetics and Genomics and the Manton Center for Orphan Disease ResearchBoston Children's HospitalBostonMAUSA
| | - Catherine A. Brownstein
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Department of PediatricsBoston Children’s Hospital and Harvard Medical SchoolBostonMAUSA
- Department of MedicineDivision of Genetics and Genomics and the Manton Center for Orphan Disease ResearchBoston Children's HospitalBostonMAUSA
| | - Eduardo Pérez‐Palma
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOHUSA
- Cologne Center for GenomicsUniversity of CologneCologneGermany
| | - Robin Haynes
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Department of PathologyBoston Children’s Hospital and Harvard Medical SchoolBostonMAUSA
| | - Dennis Lal
- Genomic Medicine InstituteLerner Research InstituteCleveland ClinicClevelandOHUSA
- Cologne Center for GenomicsUniversity of CologneCologneGermany
- Stanley Center for Psychiatric ResearchBroad Institute of Harvard and MITCambridgeMAUSA
| | - Annapurna H. Poduri
- Department of NeurologyBoston Children's Hospital and Harvard Medical SchoolBostonMAUSA
- Robert’s Program on Sudden Death in PediatricsBoston Children’s HospitalBostonMAUSA
- Stanley Center for Psychiatric ResearchBroad Institute of Harvard and MITCambridgeMAUSA
| |
Collapse
|