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Hammer MF, Pan Y, Cumbay M, Pendziwiat M, Afawi Z, Goldberg-Stern H, Johnstone L, Helbig I, Cummins TR. Whole exome sequencing and co-expression analysis identify an SCN1A variant that modifies pathogenicity in a family with genetic epilepsy and febrile seizures plus. Epilepsia 2022; 63:1970-1980. [PMID: 35592948 PMCID: PMC10753192 DOI: 10.1111/epi.17296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 05/06/2022] [Accepted: 05/06/2022] [Indexed: 01/19/2023]
Abstract
OBJECTIVE Family members carrying the same SCN1A variant often exhibit differences in the clinical severity of epilepsy. This variable expressivity suggests that other factors aside from the primary sodium channel variant influence the clinical manifestation. However, identifying such factors has proven challenging in humans. METHODS We perform whole exome sequencing (WES) in a large family in which an SCN1A variant (p.K1372E) is segregating that is associated with a broad spectrum of phenotypes ranging from lack of epilepsy, to febrile seizures and absence seizures, to Dravet syndrome. We assessed the hypothesis that the severity of the SCN1A-related phenotype was affected by alternate alleles at a modifier locus (or loci). RESULTS One of our top candidates identified by WES was a second variant in the SCN1A gene (p.L375S) that was shared exclusively by unaffected carriers of the K1372E allele. To test the hypothesized that L375S variant nullifies the loss-of-function effect of K1372E, we transiently expressed Nav1.1 carrying the two variants in HEK293T cells and compared their biophysical properties with the wild-type (WT) variant, and then co-expressed WT with K1372E or L375S with K1372E in equal quantity and tested the functional consequence. The data demonstrated that co-expression of the L375S and K1372E alleles reversed the loss-of-function property brought by the K1372E variant, whereas WT-K1372E co-expression remained partial loss-of-function. SIGNIFICANCE These results support the hypothesis that L375S counteracts the loss-of-function effect of K1372E such that individuals carrying both alleles in trans do not present epilepsy-related symptoms. We demonstrate that monogenic epilepsies with wide expressivity can be modified by additional variants in the disease gene, providing a novel framework for the gene-phenotype relationship in genetic epilepsies.
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Affiliation(s)
- Michael F. Hammer
- BIO5 Institute, University of Arizona, Tucson AZ USA
85716
- University of Arizona Genomics Core (UAGC), University of
Arizona, Tucson AZ USA 85716
| | - Yanling Pan
- Department of Biology, Indiana University-Purdue University
Indianapolis, Indianapolis IN 46202
| | - Medhane Cumbay
- Division of Biomedical Sciences, Marian University -
College of Osteopathic Medicine, Indianapolis, IN 46222
| | - Manuela Pendziwiat
- Department of Neuropediatrics, University Medical Center
Schleswig-Holstein Christian Albrechts University, Kiel, Germany
- Institute of Clinical Molecular Biology,
Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Zaid Afawi
- Center for Neuroscience, Ben-Gurion University of the
Negev, Be’er Sheva 8410402, Israel
| | | | - Laurel Johnstone
- University of Arizona Genomics Core (UAGC), University of
Arizona, Tucson AZ USA 85716
| | - Ingo Helbig
- Institute of Clinical Molecular Biology,
Christian-Albrechts-University of Kiel, Kiel, Germany
- Division of Neurology, Children’s Hospital of
Philadelphia, Philadelphia, PA, 19104 USA
- The Epilepsy NeuroGenetics Initiative (ENGIN),
Children’s Hospital of Philadelphia, Philadelphia, USA
- Department of Biomedical and Health Informatics (DBHi),
Children’s Hospital of Philadelphia, Philadelphia, PA, 19104 USA
- Department of Neurology, University of Pennsylvania,
Perelman School of Medicine, Philadelphia, PA, 19104 USA
| | - Theodore R. Cummins
- Department of Biology, Indiana University-Purdue University
Indianapolis, Indianapolis IN 46202
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Dell'Isola GB, Vinti V, Fattorusso A, Tascini G, Mencaroni E, Di Cara G, Striano P, Verrotti A. The Broad Clinical Spectrum of Epilepsies Associated With Protocadherin 19 Gene Mutation. Front Neurol 2022; 12:780053. [PMID: 35111125 PMCID: PMC8801579 DOI: 10.3389/fneur.2021.780053] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022] Open
Abstract
Protocadherin 19 (PCDH19) gene is one of the most common genes involved in epilepsy syndromes. According to literature data PCDH19 is among the 6 genes most involved in genetic epilepsies. PCDH19 is located on chromosome Xq22.1 and is involved in neuronal connections and signal transduction. The most frequent clinical expression of PCDH19 mutation is epilepsy and mental retardation limited to female (EFMR) characterized by epileptic and non-epileptic symptoms affecting mainly females. However, the phenotypic spectrum of these mutations is considerably variable from genetic epilepsy with febrile seizure plus to epileptic encephalopathies. The peculiar exclusive involvement of females seems to be caused by a cellular interference in heterozygosity, however, affected mosaic-males have been reported. Seizure types range from focal seizure to generalized tonic-clonic, tonic, atonic, absences, and myoclonic jerks. Treatment of PCDH19-related epilepsy is limited by drug resistance and by the absence of specific treatment indications. However, seizures become less severe with adolescence and some patients may even become seizure-free. Non-epileptic symptoms represent the main disabilities of adult patients with PCDH19 mutation. This review aims to analyze the highly variable phenotypic expression of PCDH19 gene mutation associated with epilepsy.
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Affiliation(s)
| | - Valerio Vinti
- Department of Pediatrics, University of Perugia, Perugia, Italy
| | | | - Giorgia Tascini
- Department of Pediatrics, University of Perugia, Perugia, Italy
| | | | | | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) “G. Gaslini” Institute, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
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Dimitrijevic S, Jekic B, Cvjeticanin S, Tucovic A, Filipovic T, Novaković I, Ivić B, Nikolic D. KCC2 rs2297201 Gene Polymorphism Might be a Predictive Genetic Marker of Febrile Seizures. ASN Neuro 2022; 14:17590914221093257. [PMID: 35414199 PMCID: PMC9016559 DOI: 10.1177/17590914221093257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Introduction: Febrile seizures (FS) are the most common neurological
disease in childhood. The etiology of FS is the subject of numerous studies
including studies regarding genetic predisposition. Aim: The aim of
the study was to analyze the association of TRPV1 rs222747 and
KCC2 rs2297201 gene polymorphisms with the occurrence of
FS. Materials and Methods: The study included 112 patients
diagnosed with FS classified as simple febrile seizures (SFS) or complex febrile
seizures (CFS). We analyzed selected polymorphisms of KCC2 and
TRPV1 genes using the Real-time PCR method.
Results: The CT and TT genotypes of the rs2297201 polymorphism
of the KCC2 gene are significantly more common in the group of
children with FS than the control group (p = .002) as well as
the allele T of this polymorphism (p = .045). Additionally,
genotypes CT and TT of the rs2297201 polymorphism of the KCC2
gene were more frequent in the group of children with CFS compared to the
control group (p < .001). Different genotypes and alleles of
the rs222747 TRPV1 gene polymorphism were not associated with
the occurrence of febrile seizures or epilepsy, nor were associated with the
occurrence of a particular type of febrile seizure (p = .252).
Conclusion: These results indicate that the CT and TT
genotypes, as well as the T allele of rs2297201 polymorphism of the
KCC2 gene, could be a predisposing factor for the FS, as
well as the occurrence of CFS.
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Affiliation(s)
- Sanja Dimitrijevic
- Special Hospital for Cerebral Palsy and Developmental Neurology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Biljana Jekic
- Institute of Human Genetics, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Suzana Cvjeticanin
- Institute of Human Genetics, School of Medicine, University of Belgrade, Belgrade, Serbia
| | | | - Tamara Filipovic
- Institute for Rehabilitation, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivana Novaković
- Institute of Human Genetics, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Bojana Ivić
- University Clinic for Gynecology and Obstetrics “Narodni front”, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Dimitrije Nikolic
- University Children’s Hospital Tiršova, School of Medicine, University of Belgrade, Belgrade, Serbia
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Pavone P, Pappalardo XG, Parano E, Falsaperla R, Marino SD, Fink JK, Ruggieri M. Fever-Associated Seizures or Epilepsy: An Overview of Old and Recent Literature Acquisitions. Front Pediatr 2022; 10:858945. [PMID: 35529330 PMCID: PMC9070101 DOI: 10.3389/fped.2022.858945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/17/2022] [Indexed: 02/06/2023] Open
Abstract
In addition to central nervous system infections, seizures and fever may occur together in several neurological disorders. Formerly, based on the clinical features and prognostic evolution, the co-association of seizure and fever included classical febrile seizures (FS) divided into simple, complex, and prolonged FS (also called febrile status epilepticus). Later, this group of disorders has been progressively indicated, with a more inclusive term, as "fever-associated seizures or epilepsy" (FASE) that encompasses: (a) FS divided into simple, complex, and prolonged FS; (b) FS plus; (c) severe myoclonic epilepsy in infancy (Dravet syndrome); (d) genetic epilepsy with FS plus; and (e) febrile infection-related epilepsy syndrome (FIRES). Among the FASE disorders, simple FS, the most common and benign condition, is rarely associated with subsequent epileptic seizures. The correlation of FS with epilepsy and other neurological disorders is highly variable. The pathogenesis of FASE is unclear but immunological and genetic factors play a relevant role and the disorders belonging to the FASE group show to have an underlying common clinical, immunological, and genetic pathway. In this study, we have reviewed and analyzed the clinical data of each of the heterogeneous group of disorders belonging to FASE.
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Affiliation(s)
- Piero Pavone
- Unit of Clinical Pediatrics, AOU "Policlinico", PO "G. Rodolico", University of Catania, Catania, Italy
| | - Xena Giada Pappalardo
- Unit of Catania, National Council of Research, Institute for Research and Biomedical Innovation (IRIB), Catania, Italy.,Department of Biomedical and Biotechnological Sciences (BIOMETEC), University of Catania, Catania, Italy
| | - Enrico Parano
- Unit of Catania, National Council of Research, Institute for Research and Biomedical Innovation (IRIB), Catania, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", University of Catania, Catania, Italy
| | - Simona Domenica Marino
- Unit of Pediatrics, Neonatology and Neonatal Intensive Care, and Pediatric Emergency, AOU "Policlinico", PO "San Marco", University of Catania, Catania, Italy
| | - John Kane Fink
- Department of Neurology and Ann Arbor Veterans Affairs Medical Center, University of Michigan, Ann Arbor, MI, United States
| | - Martino Ruggieri
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, AOU "Policlinico", PO "G. Rodolico", Catania, Italy
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Sullo F, Pasquetti E, Patanè F, Lo Bianco M, Marino SD, Polizzi A, Falsaperla R, Ruggieri M, Zanghì A, Praticò AD. SCN1A and Its Related Epileptic Phenotypes. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractEpilepsy is one of the most common neurological disorders, with a lifetime incidence of 1 in 26. Approximately two-thirds of epilepsy has a substantial genetic component in its etiology. As a result, simultaneous screening for mutations in multiple genes and performing whole exome sequencing (WES) are becoming very frequent in the clinical evaluation of children with epilepsy. In this setting, mutations in voltage-gated sodium channel (SCN) α-subunit genes are the most commonly identified cause of epilepsy, with sodium channel genes (i.e., SCN1A, SCN2A, SCN8A) being the most frequently identified causative genes. SCN1A mutations result in a wide spectrum of epilepsy phenotypes ranging from simple febrile seizures to Dravet syndrome, a severe epileptic encephalopathy. In case of mutation of SCN1A, it is also possible to observe behavioral alterations, such as impulsivity, inattentiveness, and distractibility, which can be framed in an attention deficit hyperactivity disorder (ADHD) like phenotype. Despite more than 1,200 SCN1A mutations being reported, it is not possible to assess a clear phenotype–genotype correlations. Treatment remains a challenge and seizure control is often partial and transitory.
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Affiliation(s)
- Federica Sullo
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Elisa Pasquetti
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Francesca Patanè
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Manuela Lo Bianco
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Simona D. Marino
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | - Agata Polizzi
- Chair of Pediatrics, Department of Educational Sciences, University of Catania, Catania, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | - Martino Ruggieri
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Antonio Zanghì
- Department of Medical and Surgical Sciences and Advanced Technology “G.F. Ingrassia,” University of Catania, Catania, Italy
| | - Andrea D. Praticò
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
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Ma H, Guo Y, Chen Z, Wang L, Tang Z, Zhang J, Miao Q, Zhai Q. Mutations in the sodium channel genes SCN1A, SCN3A, and SCN9A in children with epilepsy with febrile seizures plus(EFS+). Seizure 2021; 88:146-152. [PMID: 33895391 DOI: 10.1016/j.seizure.2021.04.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 11/17/2022] Open
Abstract
PURPOSE To explore disease-causing gene mutations of epilepsy with febrile seizures plus (EFS+) in Southern Chinese Han population. METHODS Blood samples and clinical data were collected from 49 Southern Han Chinese patients with EFS+. Gene screening was performed using whole-exome sequencing and panel sequencing for 485 epilepsy-related genes. The pathogenicity of variants was evaluated based on ACMG scoring and assessment of clinical concordance. RESULTS We identified 10 putatively causative sodium channel gene variants in 49 patients with EFS+, including 8 variants in SCN1A (R500Q appeared twice), one in SCN3A and one in SCN9A. All these missense mutations were inherited from maternal or paternal and were evaluated to be of uncertain significance according to ACMG. The clinical features of patients were in concordance with the EFS+ phenotype of the mutated SCN1A, SCN3A and SCN9A gene. The clinical phenotypes of 11 probands with these gene variants included febrile seizures plus (FS+, n=7), Dravet Syndrome (n=3), FS+ with focal seizures (n=1). Three probands with SCN1A variants (R500Q located in the non-voltage areas, or G1711D in the pore-forming domain) developed severe Dravet syndrome. The affected individuals with the other 6 SCN1A variants located outside the pore-forming domain showed mild phenotypes. Novel SCN3A variant ((D1688Y) and SCN9A variant (R185H) were identified in two probands respectively and both of the probands had FS+. CONCLUSION The SCN1A, SCN3A, and SCN9A gene mutations might be a pathogenic cause of EFS+ in Southern Chinese Han population.
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Affiliation(s)
- Hongxia Ma
- The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong Province, China; Department of Pediatrics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China; Department of Pediatrics, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong Province, China
| | - Yuxiong Guo
- The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong Province, China; Department of Pediatrics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - Zhihong Chen
- Department of Pediatrics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - Lingan Wang
- Department of Neurology and Rehabilitation, Guangdong Women and Children's Hospital, Guangzhou, Guangdong Province, China
| | - Zhihong Tang
- Department of Pediatrics, Dongguan City Maternal & Child Health Hospital, Dongguan, Guangdong Province, China
| | - Jingwen Zhang
- Department of Pediatrics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China
| | - Qinfei Miao
- Shantou University, Shantou, Guangdong Province, China
| | - Qiongxiang Zhai
- The Second School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong Province, China; Department of Pediatrics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong Province, China.
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7
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Weisenberg JLZ, Fitzgerald RT, Constantino JN, Winawer MR, Thio LL. Familial aggregation of status epilepticus in generalized and focal epilepsies. Neurology 2020; 95:e2140-e2149. [PMID: 32917807 DOI: 10.1212/wnl.0000000000010708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 05/08/2020] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To determine whether familial aggregation of status epilepticus (SE) occurs in a large cohort of familial common epilepsies. METHODS We used the Epilepsy Phenome/Genome Project dataset, which consisted of 2,197 participants in 1,043 family units with ≥2 members having a common generalized or nonacquired focal epilepsy (NAFE). We identified participants with a history of traditionally defined SE (TSE) (seizures ≥30 minutes) and operationally defined SE (OSE) (seizures ≥10 minutes) by chart review. We assessed familial aggregation of TSE and OSE using χ2 analysis and generalized estimating equations (GEE). RESULTS One hundred fifty-five (7%) participants in 1,043 families had ≥1 episodes of TSE. Two hundred fifty (11%) had ≥1 episodes of OSE. In a χ2 analysis, the number of family units with ≥2 members having TSE (odds ratio [OR] 4.79, 95% confidence interval [CI] 2.56-8.97) or OSE (OR 4.23, 95% CI 2.67-6.70) was greater than expected by chance. In GEE models adjusted for sex, broad epilepsy class (GE or NAFE), age at onset, and duration of epilepsy, TSE in a proband predicted TSE in a first-degree relative (OR 2.79, 95% CI 1.24-6.22), and OSE in a proband predicted OSE in a first-degree relative (OR 2.91, 95% CI 1.65-5.15). The results remained significant in models addressing epilepsy severity by incorporating the number of antiseizure medications used or epilepsy surgery. CONCLUSIONS TSE and OSE showed robust familial aggregation in a cohort of familial epilepsy independently of epilepsy severity or class, suggesting that genetic factors contribute to SE independently of the genetic cause of these epilepsies. CLINICALTRIALSGOV IDENTIFIER NCT00552045.
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Affiliation(s)
- Judith L Z Weisenberg
- From the Division of Pediatric and Developmental Neurology, Department of Neurology (J.L.Z.W., L.L.T.) and Department of Psychiatry (R.T.F., J.N.C.), Washington University, St. Louis, MO; and Department of Neurology (M.R.W.), College of Physicians and Surgeons, Columbia University, New York, NY.
| | - Robert T Fitzgerald
- From the Division of Pediatric and Developmental Neurology, Department of Neurology (J.L.Z.W., L.L.T.) and Department of Psychiatry (R.T.F., J.N.C.), Washington University, St. Louis, MO; and Department of Neurology (M.R.W.), College of Physicians and Surgeons, Columbia University, New York, NY
| | - John N Constantino
- From the Division of Pediatric and Developmental Neurology, Department of Neurology (J.L.Z.W., L.L.T.) and Department of Psychiatry (R.T.F., J.N.C.), Washington University, St. Louis, MO; and Department of Neurology (M.R.W.), College of Physicians and Surgeons, Columbia University, New York, NY
| | - Melodie R Winawer
- From the Division of Pediatric and Developmental Neurology, Department of Neurology (J.L.Z.W., L.L.T.) and Department of Psychiatry (R.T.F., J.N.C.), Washington University, St. Louis, MO; and Department of Neurology (M.R.W.), College of Physicians and Surgeons, Columbia University, New York, NY
| | - Liu Lin Thio
- From the Division of Pediatric and Developmental Neurology, Department of Neurology (J.L.Z.W., L.L.T.) and Department of Psychiatry (R.T.F., J.N.C.), Washington University, St. Louis, MO; and Department of Neurology (M.R.W.), College of Physicians and Surgeons, Columbia University, New York, NY
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Kim SH, Shim HS, Kang SM, Park H, Jin MH, Lee JH. Are there effects of lunar cycle on pediatric febrile seizure?: A single-center retrospective study (2005-2018). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 692:589-594. [PMID: 31539966 DOI: 10.1016/j.scitotenv.2019.07.077] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/25/2019] [Accepted: 07/05/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Several studies have reported an association between seizure and the lunar cycle; however, results are conflicting. Thus, we investigated whether emergency department (ED) visits due to febrile seizure (FS) or FS plus were affected by lunar cycle. METHODS We reviewed the medical records of patients who were admitted to the ED with a main diagnosis of FS or FS plus from January 1, 2005 to August 31, 2018 (13 years 8 months), a period of 4991 days with 169 lunar cycles. During that period, we collected weather data such as mean temperature, average atmospheric pressure (AP), and humidity according to lunar phase (new moon, first quarter, full moon, and third or last quarter). RESULTS A total of 1979 patients were identified. We found male predominant with a mean age of 2.62 ± 2.09 years. Acute pharyngotonsillitis was the most common cause of fever, generalized tonic-clonic seizure was the most common type of seizure, and the mean peak body temperature was 38.77 ± 0.81 °C. The lunar cycle did not affect the onset or frequency of FS after adjustment; however, several factors, including season, O3 and NO2 concentrations, and holidays, were associated with FS. CONCLUSION We did not find an association between lunar cycle and FS or FS plus. However, several factors, including season, O3, NO2, and holidays were associated with FS or FS plus.
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Affiliation(s)
- Sung Hoon Kim
- Department of Pediatrics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Haeng Seon Shim
- Department of Anesthesia and Pain Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Su Mynn Kang
- Department of Pediatrics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Hyunho Park
- Department of Anesthesia and Pain Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Mi Hyeon Jin
- Department of Biostatistics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Jun Hwa Lee
- Department of Pediatrics, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea.
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9
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Myers KA, Johnstone DL, Dyment DA. Epilepsy genetics: Current knowledge, applications, and future directions. Clin Genet 2018; 95:95-111. [PMID: 29992546 DOI: 10.1111/cge.13414] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 07/03/2018] [Accepted: 07/06/2018] [Indexed: 12/12/2022]
Abstract
The rapid pace of disease gene discovery has resulted in tremendous advances in the field of epilepsy genetics. Clinical testing with comprehensive gene panels, exomes, and genomes are now available and have led to higher diagnostic rates and insights into the underlying disease processes. As such, the contribution to the care of patients by medical geneticists, neurogeneticists and genetic counselors are significant; the dysmorphic examination, the necessary pre- and post-test counseling, the selection of the appropriate next-generation sequencing-based test(s), and the interpretation of sequencing results require a care provider to have a comprehensive working knowledge of the strengths and limitations of the available testing technologies. As the underlying mechanisms of the encephalopathies and epilepsies are better understood, there may be opportunities for the development of novel therapies based on an individual's own specific genotype. Drug screening with in vitro and in vivo models of epilepsy can potentially facilitate new treatment strategies. The future of epilepsy genetics will also probably include other-omic approaches such as transcriptomes, metabolomes, and the expanded use of whole genome sequencing to further improve our understanding of epilepsy and provide better care for those with the disease.
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Affiliation(s)
- K A Myers
- Department of Pediatrics, University of McGill, Montreal, Canada.,Research Institute of the McGill University Health Centre, Montreal, Canada
| | - D L Johnstone
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada
| | - D A Dyment
- Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Canada.,Department of Genetics, Children's Hospital of Eastern Ontario, Ottawa, Canada
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Churbanov A, Abrahamyan L. Preventing Common Hereditary Disorders through Time-Separated Twinning. BIONANOSCIENCE 2018. [DOI: 10.1007/s12668-017-0488-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Koeleman BP. What do genetic studies tell us about the heritable basis of common epilepsy? Polygenic or complex epilepsy? Neurosci Lett 2018; 667:10-16. [DOI: 10.1016/j.neulet.2017.03.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 12/23/2022]
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Klein P, Dingledine R, Aronica E, Bernard C, Blümcke I, Boison D, Brodie MJ, Brooks-Kayal AR, Engel J, Forcelli PA, Hirsch LJ, Kaminski RM, Klitgaard H, Kobow K, Lowenstein DH, Pearl PL, Pitkänen A, Puhakka N, Rogawski MA, Schmidt D, Sillanpää M, Sloviter RS, Steinhäuser C, Vezzani A, Walker MC, Löscher W. Commonalities in epileptogenic processes from different acute brain insults: Do they translate? Epilepsia 2018; 59:37-66. [PMID: 29247482 PMCID: PMC5993212 DOI: 10.1111/epi.13965] [Citation(s) in RCA: 194] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2017] [Indexed: 12/12/2022]
Abstract
The most common forms of acquired epilepsies arise following acute brain insults such as traumatic brain injury, stroke, or central nervous system infections. Treatment is effective for only 60%-70% of patients and remains symptomatic despite decades of effort to develop epilepsy prevention therapies. Recent preclinical efforts are focused on likely primary drivers of epileptogenesis, namely inflammation, neuron loss, plasticity, and circuit reorganization. This review suggests a path to identify neuronal and molecular targets for clinical testing of specific hypotheses about epileptogenesis and its prevention or modification. Acquired human epilepsies with different etiologies share some features with animal models. We identify these commonalities and discuss their relevance to the development of successful epilepsy prevention or disease modification strategies. Risk factors for developing epilepsy that appear common to multiple acute injury etiologies include intracranial bleeding, disruption of the blood-brain barrier, more severe injury, and early seizures within 1 week of injury. In diverse human epilepsies and animal models, seizures appear to propagate within a limbic or thalamocortical/corticocortical network. Common histopathologic features of epilepsy of diverse and mostly focal origin are microglial activation and astrogliosis, heterotopic neurons in the white matter, loss of neurons, and the presence of inflammatory cellular infiltrates. Astrocytes exhibit smaller K+ conductances and lose gap junction coupling in many animal models as well as in sclerotic hippocampi from temporal lobe epilepsy patients. There is increasing evidence that epilepsy can be prevented or aborted in preclinical animal models of acquired epilepsy by interfering with processes that appear common to multiple acute injury etiologies, for example, in post-status epilepticus models of focal epilepsy by transient treatment with a trkB/PLCγ1 inhibitor, isoflurane, or HMGB1 antibodies and by topical administration of adenosine, in the cortical fluid percussion injury model by focal cooling, and in the albumin posttraumatic epilepsy model by losartan. Preclinical studies further highlight the roles of mTOR1 pathways, JAK-STAT3, IL-1R/TLR4 signaling, and other inflammatory pathways in the genesis or modulation of epilepsy after brain injury. The wealth of commonalities, diversity of molecular targets identified preclinically, and likely multidimensional nature of epileptogenesis argue for a combinatorial strategy in prevention therapy. Going forward, the identification of impending epilepsy biomarkers to allow better patient selection, together with better alignment with multisite preclinical trials in animal models, should guide the clinical testing of new hypotheses for epileptogenesis and its prevention.
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Affiliation(s)
- Pavel Klein
- Mid-Atlantic Epilepsy and Sleep Center, Bethesda, MD, USA
| | | | - Eleonora Aronica
- Department of (Neuro) Pathology, Academic Medical Center and Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
| | - Christophe Bernard
- Aix Marseille Univ, Inserm, INS, Instit Neurosci Syst, Marseille, 13005, France
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Detlev Boison
- Robert Stone Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, USA
| | - Martin J Brodie
- Epilepsy Unit, West Glasgow Ambulatory Care Hospital-Yorkhill, Glasgow, UK
| | - Amy R Brooks-Kayal
- Division of Neurology, Departments of Pediatrics and Neurology, University of Colorado School of Medicine, Aurora, CO, USA
- Children's Hospital Colorado, Aurora, CO, USA
- Neuroscience Program, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Jerome Engel
- Departments of Neurology, Neurobiology, and Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, Brain Research Institute, University of California, Los Angeles, CA, USA
| | | | | | | | | | - Katja Kobow
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | | | - Phillip L Pearl
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Asla Pitkänen
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Noora Puhakka
- Department of Neurobiology, A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Michael A Rogawski
- Department of Neurology, University of California, Davis, Sacramento, CA, USA
| | | | - Matti Sillanpää
- Departments of Child Neurology and General Practice, University of Turku and Turku University Hospital, Turku, Finland
| | - Robert S Sloviter
- Department of Neurobiology, Morehouse School of Medicine, Atlanta, GA, USA
| | - Christian Steinhäuser
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, Bonn, Germany
| | - Annamaria Vezzani
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Institute for Pharmacological Research, Milan,, Italy
| | - Matthew C Walker
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
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Phenotypic analysis of 303 multiplex families with common epilepsies. Brain 2017; 140:2144-2156. [PMID: 28899008 PMCID: PMC6059182 DOI: 10.1093/brain/awx129] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/07/2017] [Accepted: 04/24/2017] [Indexed: 12/24/2022] Open
Abstract
Gene identification in epilepsy has mainly been limited to large families segregating genes of major effect and de novo mutations in epileptic encephalopathies. Many families that present with common non-acquired focal epilepsies and genetic generalized epilepsies remain unexplained. We assembled a cohort of 'genetically enriched' common epilepsies by collecting and phenotyping families containing multiple individuals with unprovoked seizures. We aimed to determine if specific clinical epilepsy features aggregate within families, and whether this segregation of phenotypes may constitute distinct 'familial syndromes' that could inform genomic analyses. Families with three or more individuals with unprovoked seizures were studied across multiple international centres. Affected individuals were phenotyped and classified according to specific electroclinical syndromes. Families were categorized based on syndromic groupings of affected family members, examined for pedigree structure and phenotypic patterns and, where possible, assigned specific familial epilepsy syndromes. A total of 303 families were assembled and analysed, comprising 1120 affected phenotyped individuals. Of the 303 families, 117 exclusively segregated generalized epilepsy, 62 focal epilepsy, and 22 were classified as genetic epilepsy with febrile seizures plus. Over one-third (102 families) were observed to have mixed epilepsy phenotypes: 78 had both generalized and focal epilepsy features within the same individual (n = 39), or within first or second degree relatives (n = 39). Among the genetic generalized epilepsy families, absence epilepsies were found to cluster within families independently of juvenile myoclonic epilepsy, and significantly more females were affected than males. Of the 62 familial focal epilepsy families, two previously undescribed familial focal syndrome patterns were evident: 15 families had posterior quadrant epilepsies, including seven with occipito-temporal localization and seven with temporo-parietal foci, and four families displayed familial focal epilepsy of childhood with multiple affected siblings that was suggestive of recessive inheritance. The findings suggest (i) specific patterns of syndromic familial aggregation occur, including newly recognized forms of familial focal epilepsy; (ii) although syndrome-specificity usually occurs in multiplex families, the one-third of families with features of both focal and generalized epilepsy is suggestive of shared genetic determinants; and (iii) patterns of features observed across families including pedigree structure, sex, and age of onset may hold clues for future gene identification. Such detailed phenotypic information will be invaluable in the conditioning and interpretation of forthcoming sequencing data to understand the genetic architecture and inter-relationships of the common epilepsy syndromes.
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Affiliation(s)
- The Epi4K Consortium
- Correspondence to: Samuel Berkovic, Epilepsy Research Centre, L2 Melbourne Brain Centre, 245 Burgundy Street, Austin Health, Heidelberg Victoria Australia 3084 E-mail:
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14
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Pokorn M, Jevšnik M, Petrovec M, Steyer A, Mrvič T, Grosek Š, Lusa L, Strle F. Respiratory and Enteric Virus Detection in Children. J Child Neurol 2017; 32:84-93. [PMID: 27698149 DOI: 10.1177/0883073816670820] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The majority of children with febrile seizures have viral infections and viruses were detected in 22% to 63% of children in published studies. Using molecular methods, viruses were also detected in asymptomatic persons. A prospective study was conducted to detect respiratory and enteric viruses in 192 children with febrile seizures and compare the detection rates to those found in 156 healthy age-matched controls. A respiratory or enteric virus was detected in 72.9% of children with febrile seizures and in 51.4% of healthy controls. The viruses most strongly associated with febrile seizures were influenza, respiratory syncytial virus, parainfluenza, human coronavirus, and rotavirus. Compared to healthy controls, the age-adjusted odds ratios for nasopharynx virus positivity in febrile seizure patients were 79.4, 2.8, 7.2, and 4.9 for influenza virus, parainfluenza virus, respiratory syncytial virus, and human coronavirus, respectively, and 22.0 for rotavirus in stool. The detected virus did not influence clinical features of febrile seizure.
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Affiliation(s)
- Marko Pokorn
- 1 Department of Infectious Diseases, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Monika Jevšnik
- 2 Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Miroslav Petrovec
- 2 Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Andrej Steyer
- 2 Institute of Microbiology and Immunology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Tatjana Mrvič
- 1 Department of Infectious Diseases, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Štefan Grosek
- 3 Department of Pediatric Surgery and Intensive Care, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Lara Lusa
- 4 Institute for Biostatistics and Medical Informatics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Franc Strle
- 1 Department of Infectious Diseases, University Medical Centre Ljubljana, Ljubljana, Slovenia
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Reid CA, Hildebrand MS, Mullen SA, Hildebrand JM, Berkovic SF, Petrou S. Synaptic Zn 2+ and febrile seizure susceptibility. Br J Pharmacol 2016; 174:119-125. [PMID: 27771943 DOI: 10.1111/bph.13658] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 10/11/2016] [Accepted: 10/17/2016] [Indexed: 12/20/2022] Open
Abstract
Zn2+ , the second most prevalent trace element in the body, is essential for supporting a wide range of biological functions. While the majority of Zn2+ in the brain is protein-bound, a significant proportion of free Zn2+ is found co-localized with glutamate in synaptic vesicles and is released in an activity-dependent manner. Clinical studies have shown Zn2+ levels are significantly lower in blood and cerebrospinal fluid of children that suffer febrile seizures. Likewise, investigations in multiple animal models demonstrate that low levels of brain Zn2+ increase seizure susceptibility. Recent work provides human genetic evidence that disruption of brain Zn2+ homeostasis at the level of the synapse is associated with increased seizure susceptibility. In this review, we have explored the clinical, functional and genetic data supporting the view that low synaptic Zn2+ increases cellular excitability and febrile seizure susceptibility. Finally, the review focuses on the potential of therapeutic Zn2+ supplementation for at risk patients.
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Affiliation(s)
- Christopher A Reid
- Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - Michael S Hildebrand
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, VIC, Australia
| | - Saul A Mullen
- Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - Joanne M Hildebrand
- Cell Signalling and Cell Death Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Samuel F Berkovic
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Heidelberg, VIC, Australia
| | - Steven Petrou
- Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
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Epilepsy After Febrile Seizures: Twins Suggest Genetic Influence. Pediatr Neurol 2016; 55:14-6. [PMID: 26638777 PMCID: PMC4747848 DOI: 10.1016/j.pediatrneurol.2015.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 10/11/2015] [Accepted: 10/22/2015] [Indexed: 11/24/2022]
Abstract
BACKGROUND A history of complex febrile seizures can increase the risk of epilepsy, but the role of genetic factors is unclear. This analysis evaluated the relationship between febrile seizures and epilepsy. METHODS Information on the history of seizures was obtained by a questionnaire from twin pairs in the Mid-Atlantic, Danish, and Norwegian Twin Registries. The information was verified using medical records and detailed clinical and family interviews. The initial study evaluated the genetic epidemiology of febrile seizures in this population. Further information was analyzed and used to evaluate genetic associations of different febrile seizure subtypes. RESULTS Histories of febrile seizures were validated in 1051 twins in 900 pairs. The febrile seizure type was classified as simple, complex, or febrile status epilepticus. There were 61% simple, 12% complex, and 7% febrile status epilepticus. There were 78 twins who developed epilepsy. The highest rate of epilepsy (22.2%) occurred in the febrile status epilepticus group. Concordance was highest in simple group. CONCLUSION A twin with febrile status epilepticus is at the highest risk of developing epilepsy, but simple febrile seizures gave the highest risk for the unaffected twin to develop seizures or other neurological issues. These results are consistent with previous findings. There is a subgroup of febrile seizures that can be associated with long-term consequences. This subgroup can be associated with a significant financial and emotional burden. It is currently not possible to accurately identify which children will develop recurrent febrile seizures, epilepsy, or neuropsychological comorbidities.
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Jongbloets BC, van Gassen KLI, Kan AA, Olde Engberink AHO, de Wit M, Wolterink-Donselaar IG, Groot Koerkamp MJA, van Nieuwenhuizen O, Holstege FCP, de Graan PNE. Expression Profiling after Prolonged Experimental Febrile Seizures in Mice Suggests Structural Remodeling in the Hippocampus. PLoS One 2015; 10:e0145247. [PMID: 26684451 PMCID: PMC4684321 DOI: 10.1371/journal.pone.0145247] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/30/2015] [Indexed: 12/11/2022] Open
Abstract
Febrile seizures are the most prevalent type of seizures among children up to 5 years of age (2–4% of Western-European children). Complex febrile seizures are associated with an increased risk to develop temporal lobe epilepsy. To investigate short- and long-term effects of experimental febrile seizures (eFS), we induced eFS in highly febrile convulsion-susceptible C57BL/6J mice at post-natal day 10 by exposure to hyperthermia (HT) and compared them to normotherm-exposed (NT) mice. We detected structural re-organization in the hippocampus 14 days after eFS. To identify molecular candidates, which entrain this structural re-organization, we investigated temporal changes in mRNA expression profiles eFS 1 hour to 56 days after eFS. We identified 931 regulated genes and profiled several candidates using in situ hybridization and histology at 3 and 14 days after eFS. This is the first study to report genome-wide transcriptome analysis after eFS in mice. We identify temporal regulation of multiple processes, such as stress-, immune- and inflammatory responses, glia activation, glutamate-glutamine cycle and myelination. Identification of the short- and long-term changes after eFS is important to elucidate the mechanisms contributing to epileptogenesis.
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Affiliation(s)
- Bart C Jongbloets
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Koen L I van Gassen
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Anne A Kan
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Anneke H O Olde Engberink
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marina de Wit
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Inge G Wolterink-Donselaar
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marian J A Groot Koerkamp
- Molecular Cancer Research, Division Biomedical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Onno van Nieuwenhuizen
- Brain Center Rudolf Magnus, Department of Pediatric Neurology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Frank C P Holstege
- Molecular Cancer Research, Division Biomedical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Pierre N E de Graan
- Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, the Netherlands
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18
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Loss of synaptic Zn2+ transporter function increases risk of febrile seizures. Sci Rep 2015; 5:17816. [PMID: 26647834 PMCID: PMC4673435 DOI: 10.1038/srep17816] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 11/06/2015] [Indexed: 01/06/2023] Open
Abstract
Febrile seizures (FS) are the most common seizure syndrome and are potentially a prelude to more severe epilepsy. Although zinc (Zn(2+)) metabolism has previously been implicated in FS, whether or not variation in proteins essential for Zn(2+) homeostasis contributes to susceptibility is unknown. Synaptic Zn(2+) is co-released with glutamate and modulates neuronal excitability. SLC30A3 encodes the zinc transporter 3 (ZNT3), which is primarily responsible for moving Zn(2+) into synaptic vesicles. Here we sequenced SLC30A3 and discovered a rare variant (c.892C > T; p.R298C) enriched in FS populations but absent in population-matched controls. Functional analysis revealed a significant loss-of-function of the mutated protein resulting from a trafficking deficit. Furthermore, mice null for ZnT3 were more sensitive than wild-type to hyperthermia-induced seizures that model FS. Together our data suggest that reduced synaptic Zn(2+) increases the risk of FS and more broadly support the idea that impaired synaptic Zn(2+) homeostasis can contribute to neuronal hyperexcitability.
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Febrile Seizures and Febrile Seizure Syndromes: An Updated Overview of Old and Current Knowledge. Neurol Res Int 2015; 2015:849341. [PMID: 26697219 PMCID: PMC4677235 DOI: 10.1155/2015/849341] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 10/26/2015] [Accepted: 10/28/2015] [Indexed: 01/04/2023] Open
Abstract
Febrile seizures are the most common paroxysmal episode during childhood, affecting up to one in 10 children. They are a major cause of emergency facility visits and a source of family distress and anxiety. Their etiology and pathophysiological pathways are being understood better over time; however, there is still more to learn. Genetic predisposition is thought to be a major contributor. Febrile seizures have been historically classified as benign; however, many emerging febrile seizure syndromes behave differently. The way in which human knowledge has evolved over the years in regard to febrile seizures has not been dealt with in depth in the current literature, up to our current knowledge. This review serves as a documentary of how scientists have explored febrile seizures, elaborating on the journey of knowledge as far as etiology, clinical features, approach, and treatment strategies are concerned. Although this review cannot cover all clinical aspects related to febrile seizures at the textbook level, we believe it can function as a quick summary of the past and current sources of knowledge for all varieties of febrile seizure types and syndromes.
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20
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Schubert J, Siekierska A, Esguerra C, Weber Y, Lerche H. V23. Mutations in STX1B encoding a presynaptic protein cause fever-associated epilepsy syndromes. Clin Neurophysiol 2015. [DOI: 10.1016/j.clinph.2015.04.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Schubert J, Siekierska A, Langlois M, May P, Huneau C, Becker F, Muhle H, Suls A, Lemke JR, de Kovel CGF, Thiele H, Konrad K, Kawalia A, Toliat MR, Sander T, Rüschendorf F, Caliebe A, Nagel I, Kohl B, Kecskés A, Jacmin M, Hardies K, Weckhuysen S, Riesch E, Dorn T, Brilstra EH, Baulac S, Møller RS, Hjalgrim H, Koeleman BPC, Jurkat-Rott K, Lehmann-Horn F, Roach JC, Glusman G, Hood L, Galas DJ, Martin B, de Witte PAM, Biskup S, De Jonghe P, Helbig I, Balling R, Nürnberg P, Crawford AD, Esguerra CV, Weber YG, Lerche H. Mutations in STX1B, encoding a presynaptic protein, cause fever-associated epilepsy syndromes. Nat Genet 2014; 46:1327-32. [DOI: 10.1038/ng.3130] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 10/06/2014] [Indexed: 01/12/2023]
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Feenstra B, Pasternak B, Geller F, Carstensen L, Wang T, Huang F, Eitson JL, Hollegaard MV, Svanström H, Vestergaard M, Hougaard DM, Schoggins JW, Jan LY, Melbye M, Hviid A. Common variants associated with general and MMR vaccine-related febrile seizures. Nat Genet 2014; 46:1274-82. [PMID: 25344690 PMCID: PMC4244308 DOI: 10.1038/ng.3129] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 10/03/2014] [Indexed: 12/28/2022]
Abstract
Febrile seizures represent a recognized serious adverse event following measles, mumps, and rubella (MMR) vaccination. We conducted a series of genome-wide association scans comparing children with MMR-related febrile seizures, children with febrile seizures unrelated to vaccination, and controls with no history of febrile seizures. Two loci were distinctly associated with MMR-related febrile seizures, harboring the interferon-stimulated gene IFI44L (rs273259; P = 5.9×10−12 vs. controls; P =1.2×10−9 vs. MMR-unrelated febrile seizures) and the measles virus receptor CD46 (rs1318653; P = 9.6×10−11 vs. controls; P = 1.6×10−9 vs. MMR-unrelated febrile seizures). Furthermore, four loci were associated with febrile seizures in general implicating the sodium channel genes SCN1A (rs6432860; P = 2.2×10−16) and SCN2A (rs3769955; P = 3.1×10−10), a TMEM16 family gene (TMEM16C; rs114444506; P = 3.7×10−20), and a region associated with magnesium levels (12q21.33; rs11105468; P = 3.4×10−11). Finally, functional relevance of TMEM16C was demonstrated with electrophysiological experiments in wild-type and knockout rats.
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Affiliation(s)
- Bjarke Feenstra
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Björn Pasternak
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Frank Geller
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Lisbeth Carstensen
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Tongfei Wang
- 1] Department of Physiology, University of California, San Francisco, San Francisco, California, USA. [2] Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, USA. [3] Howard Hughes Medical Institute, San Francisco, California, USA
| | - Fen Huang
- 1] Department of Physiology, University of California, San Francisco, San Francisco, California, USA. [2] Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, USA. [3] Howard Hughes Medical Institute, San Francisco, California, USA
| | - Jennifer L Eitson
- Department of Microbiology, University of Texas Southwestern Medical School, Dallas, Texas, USA
| | - Mads V Hollegaard
- Danish Centre for Neonatal Screening, Department of Clinical Biochemistry, Immunology and Genetics, Statens Serum Institut, Copenhagen, Denmark
| | - Henrik Svanström
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Mogens Vestergaard
- Research Unit and Section for General Practice, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - David M Hougaard
- Danish Centre for Neonatal Screening, Department of Clinical Biochemistry, Immunology and Genetics, Statens Serum Institut, Copenhagen, Denmark
| | - John W Schoggins
- Department of Microbiology, University of Texas Southwestern Medical School, Dallas, Texas, USA
| | - Lily Yeh Jan
- 1] Department of Physiology, University of California, San Francisco, San Francisco, California, USA. [2] Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, USA. [3] Howard Hughes Medical Institute, San Francisco, California, USA
| | - Mads Melbye
- 1] Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark. [2] Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark. [3] Department of Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Anders Hviid
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
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Vadlamudi L, Milne RL, Lawrence K, Heron SE, Eckhaus J, Keay D, Connellan M, Torn-Broers Y, Howell RA, Mulley JC, Scheffer IE, Dibbens LM, Hopper JL, Berkovic SF. Genetics of epilepsy: The testimony of twins in the molecular era. Neurology 2014; 83:1042-8. [PMID: 25107880 DOI: 10.1212/wnl.0000000000000790] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
OBJECTIVE Analysis of twins with epilepsy to explore the genetic architecture of specific epilepsies, to evaluate the applicability of the 2010 International League Against Epilepsy (ILAE) organization of epilepsy syndromes, and to integrate molecular genetics with phenotypic analyses. METHODS A total of 558 twin pairs suspected to have epilepsy were ascertained from twin registries (69%) or referral (31%). Casewise concordance estimates were calculated for epilepsy syndromes. Epilepsies were then grouped according to the 2010 ILAE organizational scheme. Molecular genetic information was utilized where applicable. RESULTS Of 558 twin pairs, 418 had confirmed seizures. A total of 534 twin individuals were affected. There were higher twin concordance estimates for monozygotic (MZ) than for dizygotic (DZ) twins for idiopathic generalized epilepsies (MZ = 0.77; DZ = 0.35), genetic epilepsy with febrile seizures plus (MZ = 0.85; DZ = 0.25), and focal epilepsies (MZ = 0.40; DZ = 0.03). Utilizing the 2010 ILAE scheme, the twin data clearly demonstrated genetic influences in the syndromes designated as genetic. Of the 384 tested twin individuals, 10.9% had mutations of large effect in known epilepsy genes or carried validated susceptibility alleles. CONCLUSIONS Twin studies confirm clear genetic influences for specific epilepsies. Analysis of the twin sample using the 2010 ILAE scheme strongly supported the validity of grouping the "genetic" syndromes together and shows this organizational scheme to be a more flexible and biologically meaningful system than previous classifications. Successful selected molecular testing applied to this cohort is the prelude to future large-scale next-generation sequencing of epilepsy research cohorts. Insights into genetic architecture provided by twin studies provide essential data for optimizing such approaches.
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Affiliation(s)
- Lata Vadlamudi
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Roger L Milne
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Kate Lawrence
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Sarah E Heron
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Jazmin Eckhaus
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Deborah Keay
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Mary Connellan
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Yvonne Torn-Broers
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - R Anne Howell
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - John C Mulley
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Ingrid E Scheffer
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Leanne M Dibbens
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - John L Hopper
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia
| | - Samuel F Berkovic
- From the Epilepsy Research Centre, Department of Medicine (Neurology) (L.V., K.L., J.E., D.K., M.C., Y.T.-B., R.A.H., I.E.S., S.F.B.), University of Melbourne, Austin Health; School of Medicine (L.V.), The University of Queensland, Brisbane; Department of Neurology (L.V.), Royal Brisbane and Women's Hospital; Centre for Molecular, Environmental, Analytic and Genetic Epidemiology (R.L.M., J.L.H.), University of Melbourne; School of Pharmacy and Medical Sciences and Sansom Institute for Health Research (S.E.H., L.M.D.), University of South Australia, Adelaide; and the Department of Genetic Medicine, SA Pathology (J.C.M.), Women's and Children's Hospital, North Adelaide, Australia.
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Todd E, Gurba KN, Botzolakis EJ, Stanic AK, Macdonald RL. GABAA receptor biogenesis is impaired by the γ2 subunit febrile seizure-associated mutation, GABRG2(R177G). Neurobiol Dis 2014; 69:215-24. [PMID: 24874541 DOI: 10.1016/j.nbd.2014.05.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 05/08/2014] [Accepted: 05/17/2014] [Indexed: 01/17/2023] Open
Abstract
A missense mutation in the GABAA receptor γ2L subunit, R177G, was reported in a family with complex febrile seizures (FS). To gain insight into the mechanistic basis for these genetic seizures, we explored how the R177G mutation altered the properties of recombinant α1β2γ2L GABAA receptors expressed in HEK293T cells. Using a combination of electrophysiology, flow cytometry, and immunoblotting, we found that the R177G mutation decreased GABA-evoked whole-cell current amplitudes by decreasing cell surface expression of α1β2γ2L receptors. This loss of receptor surface expression resulted from endoplasmic reticulum (ER) retention of mutant γ2L(R177G) subunits, which unlike wild-type γ2L subunits, were degraded by ER-associated degradation (ERAD). Interestingly, when compared to the condition of homozygous γ2L(R177G) subunit expression, disproportionately low levels of γ2L(R177G) subunits reached the cell surface with heterozygous expression, indicating that wild-type γ2L subunits possessed a competitive advantage over mutant γ2L(R177G) subunits for receptor assembly and/or forward trafficking. Inhibiting protein synthesis with cycloheximide demonstrated that the R177G mutation primarily decreased the stability of an intracellular pool of unassembled γ2L subunits, suggesting that the mutant γ2L(R177G) subunits competed poorly with wild-type γ2L subunits due to impaired subunit folding and/or oligomerization. Molecular modeling confirmed that the R177G mutation could disrupt intrasubunit salt bridges, thereby destabilizing secondary and tertiary structure of γ2L(R177G) subunits. These findings support an emerging body of literature implicating defects in GABAA receptor biogenesis in the pathogenesis of genetic epilepsies (GEs) and FS.
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Affiliation(s)
- Emily Todd
- Program in Neuroscience, Vanderbilt University, Nashville, TN 37232, USA
| | - Katharine N Gurba
- Program in Neuroscience, Vanderbilt University, Nashville, TN 37232, USA
| | | | | | - Robert L Macdonald
- Department of Neurology, Vanderbilt University, Nashville, TN 37232, USA; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN 37232, USA.
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25
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Millichap JG, Millichap JJ. Genetic Factor in Etiology of Febrile Seizures. Pediatr Neurol Briefs 2014. [DOI: 10.15844/pedneurbriefs-28-5-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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26
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Hessel EVS, de Wit M, Wolterink-Donselaar IG, Karst H, de Graaff E, van Lith HA, de Bruijn E, de Sonnaville S, Verbeek NE, Lindhout D, de Kovel CGF, Koeleman BPC, van Kempen M, Brilstra E, Cuppen E, Loos M, Spijker SS, Kan AA, Baars SE, van Rijen PC, Gosselaar PH, Groot Koerkamp MJA, Holstege FCP, van Duijn C, Vergeer J, Moll HA, Taubøll E, Heuser K, Ramakers GMJ, Pasterkamp RJ, van Nieuwenhuizen O, Hoogenraad CC, Kas MJH, de Graan PNE. Identification of Srp9 as a febrile seizure susceptibility gene. Ann Clin Transl Neurol 2014; 1:239-50. [PMID: 25590037 PMCID: PMC4292741 DOI: 10.1002/acn3.48] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 02/07/2014] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE Febrile seizures (FS) are the most common seizure type in young children. Complex FS are a risk factor for mesial temporal lobe epilepsy (mTLE). To identify new FS susceptibility genes we used a forward genetic strategy in mice and subsequently analyzed candidate genes in humans. METHODS We mapped a quantitative trait locus (QTL1) for hyperthermia-induced FS on mouse chromosome 1, containing the signal recognition particle 9 (Srp9) gene. Effects of differential Srp9 expression were assessed in vivo and in vitro. Hippocampal SRP9 expression and genetic association were analyzed in FS and mTLE patients. RESULTS Srp9 was differentially expressed between parental strains C57BL/6J and A/J. Chromosome substitution strain 1 (CSS1) mice exhibited lower FS susceptibility and Srp9 expression than C57BL/6J mice. In vivo knockdown of brain Srp9 reduced FS susceptibility. Mice with reduced Srp9 expression and FS susceptibility, exhibited reduced hippocampal AMPA and NMDA currents. Downregulation of neuronal Srp9 reduced surface expression of AMPA receptor subunit GluA1. mTLE patients with antecedent FS had higher SRP9 expression than patients without. SRP9 promoter SNP rs12403575(G/A) was genetically associated with FS and mTLE. INTERPRETATION Our findings identify SRP9 as a novel FS susceptibility gene and indicate that SRP9 conveys its effects through endoplasmic reticulum (ER)-dependent synthesis and trafficking of membrane proteins, such as glutamate receptors. Discovery of this new FS gene and mechanism may provide new leads for early diagnosis and treatment of children with complex FS at risk for mTLE.
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Affiliation(s)
- Ellen V S Hessel
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Marina de Wit
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Inge G Wolterink-Donselaar
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Henk Karst
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Esther de Graaff
- Cell Biology, Faculty of Science, Utrecht UniversityUtrecht, The Netherlands
| | - Hein A van Lith
- Program Emotion and Cognition, Division of Animal Welfare and Laboratory Animal Science, Department of Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University and Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Ewart de Bruijn
- Hubrecht Institute-KNAW and University Medical Center UtrechtUtrecht, The Netherlands
| | - Sophietje de Sonnaville
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Nienke E Verbeek
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Dick Lindhout
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
- SEIN Epilepsy Institute in the NetherlandsHeemstede, The Netherlands
| | - Carolien G F de Kovel
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Bobby P C Koeleman
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Marjan van Kempen
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Eva Brilstra
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Edwin Cuppen
- Hubrecht Institute-KNAW and University Medical Center UtrechtUtrecht, The Netherlands
- Department of Medical Genetics, University Medical Center UtrechtUtrecht, The Netherlands
| | - Maarten Loos
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU UniversityAmsterdam, The Netherlands
| | - Sabine S Spijker
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU UniversityAmsterdam, The Netherlands
| | - Anne A Kan
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Susanne E Baars
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
- Master program Neuroscience and Cognition, Utrecht UniversityUtrecht, The Netherlands
| | - Peter C van Rijen
- Department of Neurosurgery, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Peter H Gosselaar
- Department of Neurosurgery, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | | | - Frank C P Holstege
- Department of Molecular Cancer Research, University Medical Center UtrechtUtrecht, The Netherlands
| | - Cornelia van Duijn
- Department of Epidemiology, Erasmus University Medical CenterRotterdam, The Netherlands
| | - Jeanette Vergeer
- Department of Epidemiology, Erasmus University Medical CenterRotterdam, The Netherlands
| | - Henriette A Moll
- Department of Pediatrics, Erasmus Medical CenterRotterdam, The Netherlands
| | - Erik Taubøll
- Department of Neurology, Oslo University HospitalOslo, Norway
| | - Kjell Heuser
- Department of Neurology, Oslo University HospitalOslo, Norway
| | - Geert M J Ramakers
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Onno van Nieuwenhuizen
- Department of Child Neurology, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Casper C Hoogenraad
- Cell Biology, Faculty of Science, Utrecht UniversityUtrecht, The Netherlands
| | - Martien J H Kas
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
| | - Pierre N E de Graan
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, The Netherlands
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27
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Abstract
Febrile seizures are common and mostly benign. They are the most common cause of seizures in children less than five years of age. There are two categories of febrile seizures, simple and complex. Both the International League against Epilepsy and the National Institute of Health has published definitions on the classification of febrile seizures. Simple febrile seizures are mostly benign, but a prolonged (complex) febrile seizure can have long term consequences. Most children who have a febrile seizure have normal health and development after the event, but there is recent evidence that suggests a small subset of children that present with seizures and fever may have recurrent seizure or develop epilepsy. This review will give an overview of the definition of febrile seizures, epidemiology, evaluation, treatment, outcomes and recent research.
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Affiliation(s)
- DO Syndi Seinfeld
- Department of Neurology, Virginia Commonwealth University, Richmond, USA
| | - John M Pellock
- Department of Neurology, Virginia Commonwealth University, Richmond, USA
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