1
|
Fan HC, Yang MT, Lin LC, Chiang KL, Chen CM. Clinical and Genetic Features of Dravet Syndrome: A Prime Example of the Role of Precision Medicine in Genetic Epilepsy. Int J Mol Sci 2023; 25:31. [PMID: 38203200 PMCID: PMC10779156 DOI: 10.3390/ijms25010031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/14/2023] [Accepted: 12/17/2023] [Indexed: 01/12/2024] Open
Abstract
Dravet syndrome (DS), also known as severe myoclonic epilepsy of infancy, is a rare and drug-resistant form of developmental and epileptic encephalopathies, which is both debilitating and challenging to manage, typically arising during the first year of life, with seizures often triggered by fever, infections, or vaccinations. It is characterized by frequent and prolonged seizures, developmental delays, and various other neurological and behavioral impairments. Most cases result from pathogenic mutations in the sodium voltage-gated channel alpha subunit 1 (SCN1A) gene, which encodes a critical voltage-gated sodium channel subunit involved in neuronal excitability. Precision medicine offers significant potential for improving DS diagnosis and treatment. Early genetic testing enables timely and accurate diagnosis. Advances in our understanding of DS's underlying genetic mechanisms and neurobiology have enabled the development of targeted therapies, such as gene therapy, offering more effective and less invasive treatment options for patients with DS. Targeted and gene therapies provide hope for more effective and personalized treatments. However, research into novel approaches remains in its early stages, and their clinical application remains to be seen. This review addresses the current understanding of clinical DS features, genetic involvement in DS development, and outcomes of novel DS therapies.
Collapse
Affiliation(s)
- Hueng-Chuen Fan
- Department of Pediatrics, Tungs’ Taichung Metroharbor Hospital, Wuchi, Taichung 435, Taiwan;
- Department of Rehabilitation, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli 356, Taiwan
- Department of Life Sciences, Agricultural Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan
| | - Ming-Tao Yang
- Department of Pediatrics, Far Eastern Memorial Hospital, New Taipei City 220, Taiwan;
- Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan 320, Taiwan
| | - Lung-Chang Lin
- Department of Pediatrics, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan;
- Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Kuo-Liang Chiang
- Department of Pediatric Neurology, Kuang-Tien General Hospital, Taichung 433, Taiwan;
- Department of Nutrition, Hungkuang University, Taichung 433, Taiwan
| | - Chuan-Mu Chen
- Department of Life Sciences, Agricultural Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan
- The iEGG and Animal Biotechnology Center, and Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung 402, Taiwan
| |
Collapse
|
2
|
Freibauer A, Wohlleben M, Boelman C. STXBP1-Related Disorders: Clinical Presentation, Molecular Function, Treatment, and Future Directions. Genes (Basel) 2023; 14:2179. [PMID: 38137001 PMCID: PMC10742812 DOI: 10.3390/genes14122179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 11/27/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
In recent years, the affordability and availability of genetic testing have led to its increased use in clinical care. The increased frequency of testing has led to STXBP1 variants being identified as one of the more common variants associated with neurological disorders. In this review, we aim to summarize the common clinical phenotypes associated with STXBP1 pathogenic variants, provide an overview of their known natural history, and discuss current research into the genotype to phenotype correlation. We will also provide an overview of the suspected normal function of the STXBP1-encoded Munc18-1 protein, animal models, and experimental techniques that have been developed to study its function and use this information to try to explain the diverse phenotypes associated with STXBP1-related disorders. Finally, we will explore current therapies for STXBP1 disorders, including an overview of treatment goals for STXBP1-related disorders, a discussion of the current evidence for therapies, and future directions of personalized medications for STXBP1-related disorders.
Collapse
Affiliation(s)
- Alexander Freibauer
- Division of Neurology, BC Children’s Hospital, Vancouver, BC V6H 3N1, Canada;
- Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Mikayla Wohlleben
- Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Cyrus Boelman
- Division of Neurology, BC Children’s Hospital, Vancouver, BC V6H 3N1, Canada;
- Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| |
Collapse
|
3
|
Ünalp A, Güzin Y, Ünay B, Tosun A, Çavuşoğlu D, Tekin HG, Kurul SH, Arhan E, Edizer S, Öztürk G, Yiş U, Yılmaz Ü. Retracted: Clinical and genetic evaluations of rare childhood epilepsies in Turkey's national cohort. Epileptic Disord 2023; 25:924. [PMID: 37584621 DOI: 10.1002/epd2.20150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 12/25/2022] [Accepted: 08/10/2023] [Indexed: 08/17/2023]
Abstract
Aycan Ünalp, Yiğithan Güzin, Bülent Ünay, Ayşe Tosun, Dilek Çavuşoğlu, Hande Gazeteci Tekin, Semra Hız Kurul, Ebru Arhan, Selvinaz Edizer, Gülten Öztürk, Uluç Yiş, Ünsal Yılmaz, Turkish Rare Epilepsies Study Group, Clinical and genetic evaluations of rare childhood epilepsies in Turkey's national cohort, Epileptic Disorders, 2023, (https://doi.org/10.1002/epd2.20150) The above article, published online on 16 August 2023 on Wiley Online Library (www.onlinelibrary.wiley.com), has been retracted by agreement between the authors, the Editor-in-Chief, Sándor Beniczky, and John Wiley & Sons Ltd. The authors asked for a retraction based on an experimental error which would alter the results of the study if corrected.
Collapse
|
4
|
Sills GJ. Pharmacological diversity amongst approved and emerging antiseizure medications for the treatment of developmental and epileptic encephalopathies. Ther Adv Neurol Disord 2023; 16:17562864231191000. [PMID: 37655228 PMCID: PMC10467199 DOI: 10.1177/17562864231191000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 07/13/2023] [Indexed: 09/02/2023] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are rare neurodevelopmental disorders characterised by early-onset and often intractable seizures and developmental delay/regression, and include Dravet syndrome and Lennox-Gastaut syndrome (LGS). Rufinamide, fenfluramine, stiripentol, cannabidiol and ganaxolone are antiseizure medications (ASMs) with diverse mechanisms of action that have been approved for treating specific DEEs. Rufinamide is thought to suppress neuronal hyperexcitability by preventing the functional recycling of voltage-gated sodium channels from the inactivated to resting state. It is licensed for adjunctive treatment of seizures associated with LGS. Fenfluramine increases extracellular serotonin levels and may reduce seizures via activation of specific serotonin receptors and positive modulation of the sigma-1 receptor. Fenfluramine is licensed for adjunctive treatment of seizures associated with Dravet syndrome and LGS. Stiripentol is a positive allosteric modulator of type-A gamma-aminobutyric acid (GABAA) receptors. As a broad-spectrum inhibitor of cytochrome P450 enzymes, its antiseizure effects may additionally arise through pharmacokinetic interactions with co-administered ASMs. Stiripentol is licensed for treating seizures associated with Dravet syndrome in patients taking clobazam and/or valproate. The mechanism(s) of action of cannabidiol remains largely unclear although multiple targets have been proposed, including transient receptor potential vanilloid 1, G protein-coupled receptor 55 and equilibrative nucleoside transporter 1. Cannabidiol is licensed as adjunctive treatment in conjunction with clobazam for seizures associated with Dravet syndrome and LGS, and as adjunctive treatment of seizures associated with tuberous sclerosis complex. Like stiripentol, ganaxolone is a positive allosteric modulator at GABAA receptors. It has recently been licensed in the USA for the treatment of seizures associated with cyclin-dependent kinase-like 5 deficiency disorder. Greater understanding of the causes of DEEs has driven research into the potential use of other novel and repurposed agents. Putative ASMs currently in clinical development for use in DEEs include soticlestat, carisbamate, verapamil, radiprodil, clemizole and lorcaserin.
Collapse
Affiliation(s)
- Graeme J. Sills
- School of Life Sciences, University of Glasgow, Room 341, Sir James Black Building, Glasgow G12 8QQ, UK
| |
Collapse
|
5
|
Paulhus K, Glasscock E. Novel Genetic Variants Expand the Functional, Molecular, and Pathological Diversity of KCNA1 Channelopathy. Int J Mol Sci 2023; 24:8826. [PMID: 37240170 PMCID: PMC10219020 DOI: 10.3390/ijms24108826] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/11/2023] [Accepted: 05/13/2023] [Indexed: 05/28/2023] Open
Abstract
The KCNA1 gene encodes Kv1.1 voltage-gated potassium channel α subunits, which are crucial for maintaining healthy neuronal firing and preventing hyperexcitability. Mutations in the KCNA1 gene can cause several neurological diseases and symptoms, such as episodic ataxia type 1 (EA1) and epilepsy, which may occur alone or in combination, making it challenging to establish simple genotype-phenotype correlations. Previous analyses of human KCNA1 variants have shown that epilepsy-linked mutations tend to cluster in regions critical for the channel's pore, whereas EA1-associated mutations are evenly distributed across the length of the protein. In this review, we examine 17 recently discovered pathogenic or likely pathogenic KCNA1 variants to gain new insights into the molecular genetic basis of KCNA1 channelopathy. We provide the first systematic breakdown of disease rates for KCNA1 variants in different protein domains, uncovering potential location biases that influence genotype-phenotype correlations. Our examination of the new mutations strengthens the proposed link between the pore region and epilepsy and reveals new connections between epilepsy-related variants, genetic modifiers, and respiratory dysfunction. Additionally, the new variants include the first two gain-of-function mutations ever discovered for KCNA1, the first frameshift mutation, and the first mutations located in the cytoplasmic N-terminal domain, broadening the functional and molecular scope of KCNA1 channelopathy. Moreover, the recently identified variants highlight emerging links between KCNA1 and musculoskeletal abnormalities and nystagmus, conditions not typically associated with KCNA1. These findings improve our understanding of KCNA1 channelopathy and promise to enhance personalized diagnosis and treatment for individuals with KCNA1-linked disorders.
Collapse
Affiliation(s)
| | - Edward Glasscock
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA;
| |
Collapse
|
6
|
High Performance of a Dominant/X-Linked Gene Panel in Patients with Neurodevelopmental Disorders. Genes (Basel) 2023; 14:genes14030708. [PMID: 36980980 PMCID: PMC10048137 DOI: 10.3390/genes14030708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/06/2023] [Accepted: 03/12/2023] [Indexed: 03/15/2023] Open
Abstract
Neurodevelopmental disorders (NDDs) affect 2–5% of the population and approximately 50% of cases are due to genetic factors. Since de novo pathogenic variants account for the majority of cases, a gene panel including 460 dominant and X-linked genes was designed and applied to 398 patients affected by intellectual disability (ID)/global developmental delay (GDD) and/or autism (ASD). Pathogenic variants were identified in 83 different genes showing the high genetic heterogeneity of NDDs. A molecular diagnosis was established in 28.6% of patients after high-depth sequencing and stringent variant filtering. Compared to other available gene panel solutions for NDD molecular diagnosis, our panel has a higher diagnostic yield for both ID/GDD and ASD. As reported previously, a significantly higher diagnostic yield was observed: (i) in patients affected by ID/GDD compared to those affected only by ASD, and (ii) in females despite the higher proportion of males among our patients. No differences in diagnostic rates were found between patients affected by different levels of ID severity. Interestingly, patients harboring pathogenic variants presented different phenotypic features, suggesting that deep phenotypic profiling may help in predicting the presence of a pathogenic variant. Despite the high performance of our panel, whole exome-sequencing (WES) approaches may represent a more robust solution. For this reason, we propose the list of genes included in our customized gene panel and the variant filtering procedure presented here as a first-tier approach for the molecular diagnosis of NDDs in WES studies.
Collapse
|
7
|
Scheffer IE, Bennett CA, Gill D, de Silva MG, Boggs K, Marum J, Baker N, Palmer EE, Howell KB. Exome sequencing for patients with developmental and epileptic encephalopathies in clinical practice. Dev Med Child Neurol 2023; 65:50-57. [PMID: 35701389 PMCID: PMC10952465 DOI: 10.1111/dmcn.15308] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/07/2022] [Accepted: 05/02/2022] [Indexed: 11/28/2022]
Abstract
AIM To assess the clinical utility of exome sequencing for patients with developmental and epileptic encephalopathies (DEEs). METHOD Over 2 years, patients with DEEs were recruited for singleton exome sequencing. Parental segregation was performed where indicated. RESULTS Of the 103 patients recruited (54 males, 49 females; aged 2 weeks-17 years), the genetic aetiology was identified in 36 out of 103 (35%) with management implications in 13 out of 36. Exome sequencing revealed pathogenic or likely pathogenic variants in 30 out of 103 (29%) patients, variants of unknown significance in 39 out of 103 (38%), and 34 out of 103 (33%) were negative on exome analysis. After the description of new genetic diseases, a molecular diagnosis was subsequently made for six patients or through newly available high-density chromosomal microarray testing. INTERPRETATION We demonstrate the utility of exome sequencing in routine clinical care of children with DEEs. We highlight that molecular diagnosis often leads to changes in management and informs accurate prognostic and reproductive counselling. Our findings reinforce the need for ongoing analysis of genomic data to identify the aetiology in patients in whom the cause is unknown. The implementation of genomic testing in the care of children with DEEs should become routine in clinical practice. WHAT THIS PAPER ADDS The cause was identified in 35% of patients with developmental and epileptic encephalopathies. KCNQ2, CDKL5, SCN1A, and STXBP1 were the most frequently identified genes. Reanalysis of genomic data found the cause in an additional six patients. Genetic aetiology was identified in 41% of children with seizure onset under 2 years, compared to 18% with older onset. Finding the molecular cause led to management changes in 36% of patients with DEEs.
Collapse
Affiliation(s)
- Ingrid E. Scheffer
- Epilepsy Research Centre, Department of Medicine, Austin HealthThe University of MelbourneHeidelbergVictoria
- Department of PaediatricsThe University of MelbourneVictoria
- Florey Institute of Neuroscience and Mental HealthHeidelbergVictoria
- Murdoch Children's Research InstituteParkvilleVictoria
| | - Caitlin A. Bennett
- Epilepsy Research Centre, Department of Medicine, Austin HealthThe University of MelbourneHeidelbergVictoria
| | - Deepak Gill
- TY Nelson Department of Neurology and NeurosurgeryThe Children's Hospital at WestmeadNew South Wales
| | - Michelle G. de Silva
- Victorian Clinical Genetics Services, Murdoch Children's Research InstituteRoyal Children's HospitalParkvilleVictoria
- Australian Genomics Health AllianceMelbourne
| | - Kirsten Boggs
- Australian Genomics Health AllianceMelbourne
- Sydney Children's Hospitals NetworkSydney
| | - Justine Marum
- Victorian Clinical Genetics Services, Murdoch Children's Research InstituteRoyal Children's HospitalParkvilleVictoria
| | - Naomi Baker
- Department of PaediatricsThe University of MelbourneVictoria
- Victorian Clinical Genetics Services, Murdoch Children's Research InstituteRoyal Children's HospitalParkvilleVictoria
| | | | - Katherine B. Howell
- Department of PaediatricsThe University of MelbourneVictoria
- Murdoch Children's Research InstituteParkvilleVictoria
- Department of NeurologyThe Royal Children's HospitalParkvilleVictoriaAustralia
| |
Collapse
|
8
|
Dilber C, YĂĽcel G, Ĺžahin Y. Novel homozygous AP3B2 mutations in four individuals with developmental and epileptic encephalopathy: A rare clinical entity. Clin Neurol Neurosurg 2022; 223:107509. [PMID: 36356440 DOI: 10.1016/j.clineuro.2022.107509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/18/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVES Developmental and epileptic encephalopathies (DEEs) are heterogeneous severe neurodevelopmental disorders characterized by recurrent clinical seizures that begin in the neonatal period and early childhood and regression or delay in cognitive, sensory and motor skills in the context of accompanying epileptiform abnormalities. Adaptor-related protein complex 3 beta-2 subunit (AP3B2) gene variants are thought to cause disruption of neuron-specific neurotransmitter release. METHODS In this case report, whole exome sequencing (WES) was performed on two of the four pediatric patients who came from two unrelated families and were affected by DEE. As a result of WES, previously unreported variants, that is, p.Ala149Serfs*Â 34 and p.Pro993Argfs*Â 5, were detected in the AP3B2 gene. These variants were studied using Sanger sequencing in the siblings affected by DEE of the said pediatric patients and in their healthy parents. RESULTS Autosomal recessive variants of the AP3B2 are associated with the development of DEE. To date, only 14 cases of AP3B2 mutations have been reported in the literature. Consequentially, DEE phenotype involving severe global developmental delay emerged, which is characterized by early-onset infantile epileptic encephalopathy, severe hypotonia, postnatal microcephaly, poor eye contact, speech retardation, abnormal involuntary movements, stereotypical hand movements, progressive intellectual disability, and behavioral and neuropsychiatric findings. CONCLUSION Given the limited number of patients reported in the literature, detailed studies of the specific clinical and molecular features of AP3B2 gene variants, will shed light on the genotype-phenotype correlation.
Collapse
Affiliation(s)
- Cengiz Dilber
- Department of Pediatric Neurology, Sütçü İmam Universty Faculty of Medicine, Kahramanmaraş, Turkey.
| | - GĂĽl YĂĽcel
- Department of Pediatric Neurology, Konya City Hospital, Konya, Turkey.
| | - Yavuz Ĺžahin
- Department of Medical Genetics, Genoks Genetic Diseases Diagnosis Center, Gaziantep, Turkey.
| |
Collapse
|
9
|
Li S, Yu S, Zhang Y, Wang Y, Jiang X, Wu C. Compound heterozygous loss-of-function variants in BRAT1 cause lethal neonatal rigidity and multifocal seizure syndrome. Mol Genet Genomic Med 2022; 11:e2092. [PMID: 36367347 PMCID: PMC9834191 DOI: 10.1002/mgg3.2092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/30/2022] [Accepted: 10/27/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Lethal neonatal rigidity and multifocal seizure syndrome (RMFSL, OMIM 614498) is a rare autosomal recessive disease characterized by the onset of rigidity and intractable seizures at or soon after birth. The BRAT1 has been identified to be the disease-causing gene for RMFSL. This study aimed to determine the underlying pathogenic mutations of a Chinese family with RMFSL and to confirm the effect of the splice-site mutation by reverse transcription analysis. METHODS Detailed family history and clinical data were recorded, and peripheral blood samples were collected from all available family members. Whole exome sequencing (WES), Sanger sequencing, and bioinformatics analysis were performed to investigate the causative variants. The impact of the intronic variant on splicing was subsequently analyzed by RT-PCR analysis. RESULTS We identified two compound heterozygous variants in the BRAT1, c.431-2A>G in intron 3 and c.1359_1361del(p.Leu454del) in exon 9 in the proband, one inherited from each parent. Furthermore, the 3'-splice site acceptor (c.431-2A>G) variant was found to activate a cryptic acceptor splice site, which resulted in the loss of 29 nucleotides and generation of a premature stop codon at code 180, producing a truncated BRAT1 (c.432_460del; p.Ala145Argfs*36). CONCLUSIONS This research identified two mutations in the BRAT1 of one Chinese family with RMFSL. These data can aid in developing clinical diagnoses as well as providing genetic counseling and prenatal interventions to the family. These findings also expand our knowledge of the spectrum of BRAT1 pathogenic variants in RMFSL syndrome.
Collapse
Affiliation(s)
- Shan Li
- Department of Molecular OrthopaedicsBeijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan HospitalBeijingChina
| | - Shunan Yu
- Department of Molecular OrthopaedicsBeijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan HospitalBeijingChina
| | - Yanzhuo Zhang
- Department of Molecular OrthopaedicsBeijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan HospitalBeijingChina
| | - Ying Wang
- Department of Molecular OrthopaedicsBeijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan HospitalBeijingChina
| | - Xu Jiang
- Department of Orthopaedics, Beijing Jishuitan HospitalThe Fourth Clinical Medical College of Peking UniversityBeijingChina
| | - Chengai Wu
- Department of Molecular OrthopaedicsBeijing Research Institute of Traumatology and Orthopaedics, Beijing Jishuitan HospitalBeijingChina
| |
Collapse
|
10
|
Miceli F, Millevert C, Soldovieri MV, Mosca I, Ambrosino P, Carotenuto L, Schrader D, Lee HK, Riviello J, Hong W, Risen S, Emrick L, Amin H, Ville D, Edery P, de Bellescize J, Michaud V, Van-Gils J, Goizet C, Willemsen MH, Kleefstra T, Møller RS, Bayat A, Devinsky O, Sands T, Korenke GC, Kluger G, Mefford HC, Brilstra E, Lesca G, Milh M, Cooper EC, Taglialatela M, Weckhuysen S. KCNQ2 R144 variants cause neurodevelopmental disability with language impairment and autistic features without neonatal seizures through a gain-of-function mechanism. EBioMedicine 2022; 81:104130. [PMID: 35780567 PMCID: PMC9254340 DOI: 10.1016/j.ebiom.2022.104130] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 06/08/2022] [Accepted: 06/10/2022] [Indexed: 01/10/2023] Open
Abstract
Background Prior studies have revealed remarkable phenotypic heterogeneity in KCNQ2-related disorders, correlated with effects on biophysical features of heterologously expressed channels. Here, we assessed phenotypes and functional properties associated with KCNQ2 missense variants R144W, R144Q, and R144G. We also explored in vitro blockade of channels carrying R144Q mutant subunits by amitriptyline. Methods Patients were identified using the RIKEE database and through clinical collaborators. Phenotypes were collected by a standardized questionnaire. Functional and pharmacological properties of variant subunits were analyzed by whole-cell patch-clamp recordings. Findings Detailed clinical information on fifteen patients (14 novel and 1 previously published) was analyzed. All patients had developmental delay with prominent language impairment. R144Q patients were more severely affected than R144W patients. Infantile to childhood onset epilepsy occurred in 40%, while 67% of sleep-EEGs showed sleep-activated epileptiform activity. Ten patients (67%) showed autistic features. Activation gating of homomeric Kv7.2 R144W/Q/G channels was left-shifted, suggesting gain-of-function effects. Amitriptyline blocked channels containing Kv7.2 and Kv7.2 R144Q subunits. Interpretation Patients carrying KCNQ2 R144 gain-of-function variants have developmental delay with prominent language impairment, autistic features, often accompanied by infantile- to childhood-onset epilepsy and EEG sleep-activated epileptiform activity. The absence of neonatal seizures is a robust and important clinical differentiator between KCNQ2 gain-of-function and loss-of-function variants. The Kv7.2/7.3 channel blocker amitriptyline might represent a targeted treatment. Funding Supported by FWO, GSKE, KCNQ2-Cure, Jack Pribaz Foundation, European Joint Programme on Rare Disease 2020, the Italian Ministry for University and Research, the Italian Ministry of Health, the European Commission, the University of Antwerp, NINDS, and Chalk Family Foundation.
Collapse
|
11
|
CDKL5 Deficiency Disorder-Related Epilepsy: A Review of Current and Emerging Treatment. CNS Drugs 2022; 36:591-604. [PMID: 35633486 PMCID: PMC9876658 DOI: 10.1007/s40263-022-00921-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/10/2022] [Indexed: 01/27/2023]
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a developmental and epileptic encephalopathy with infantile-onset epilepsy. Most individuals with CDD develop refractory epilepsy with multiple seizure types. Management of seizures in CDD remains challenging for clinicians given the highly refractory nature of seizures and the limited number of disease-specific studies that offer a high level of evidence. Epileptic spasms are the most common seizure type in CDD and are more often refractory to standard first-line treatment than are spasms of other etiologies. In other seizure types, the effectiveness of antiseizure medications is limited and wanes over time. Ketogenic diet and palliative surgical treatments have both had mixed results in observational studies. When treating refractory seizures in CDD, we recommend carefully balancing seizure control and treatment-related side effects to optimize each individual's overall quality of life. Clinical trials of medications targeting epilepsy in CDD have been conducted, and additional investigational small molecules, gene therapy, and other disease-modifying therapies are in development for CDD.
Collapse
|
12
|
Balagura G, Xian J, Riva A, Marchese F, Ben Zeev B, Rios L, Sirsi D, Accorsi P, Amadori E, Astrea G, Baldassari S, Beccaria F, Boni A, Budetta M, Cantalupo G, Capovilla G, Cesaroni E, Chiesa V, Coppola A, Dilena R, Faggioli R, Ferrari A, Fiorini E, Madia F, Gennaro E, Giacomini T, Giordano L, Iacomino M, Lattanzi S, Marini C, Mancardi MM, Mastrangelo M, Messana T, Minetti C, Nobili L, Papa A, Parmeggiani A, Pisano T, Russo A, Salpietro V, Savasta S, Scala M, Accogli A, Scelsa B, Scudieri P, Spalice A, Specchio N, Trivisano M, Tzadok M, Valeriani M, Vari MS, Verrotti A, Vigevano F, Vignoli A, Toonen R, Zara F, Helbig I, Striano P. Epilepsy Course and Developmental Trajectories in STXBP1-DEE. Neurol Genet 2022; 8:e676. [PMID: 35655584 PMCID: PMC9157582 DOI: 10.1212/nxg.0000000000000676] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 03/14/2022] [Indexed: 01/18/2023]
Abstract
Background and Objectives Clinical manifestations in STXBP1 developmental and epileptic encephalopathy (DEE) vary in severity and outcome, and the genotypic spectrum is diverse. We aim to trace the neurodevelopmental trajectories in individuals with STXBP1-DEE and dissect the relationship between neurodevelopment and epilepsy. Methods Retrospective standardized clinical data were collected through international collaboration. A composite neurodevelopmental score system compared the developmental trajectories in STXBP1-DEE. Results Forty-eight patients with de novo STXBP1 variants and a history of epilepsy were included (age range at the time of the study: 10 months to 35 years, mean 8.5 years). At the time of inclusion, 65% of individuals (31/48) had active epilepsy, whereas 35% (17/48) were seizure free, and 76% of those (13/17) achieved remission within the first year of life. Twenty-two individuals (46%) showed signs of developmental impairment and/or neurologic abnormalities before epilepsy onset. Age at seizure onset correlated with severity of developmental outcome and the developmental milestones achieved, with a later seizure onset associated with better developmental outcome. In contrast, age at seizure remission and epilepsy duration did not affect neurodevelopmental outcomes. Overall, we did not observe a clear genotype-phenotype correlation, but monozygotic twins with de novo STXBP1 variant showed similar phenotype and parallel disease course. Discussion The disease course in STXBP1-DEE presents with 2 main trajectories, with either early seizure remission or drug-resistant epilepsy, and a range of neurodevelopmental outcomes from mild to profound intellectual disability. Age at seizure onset is the only epilepsy-related feature associated with neurodevelopment outcome. These findings can inform future dedicated natural history studies and trial design.
Collapse
|
13
|
Shin GJ, Na JH, Lee H, Lee YM. A Case of Intellectual Disability without Epilepsy Associated with a Pathogenic Variant of <i>STXBP1</i>. ANNALS OF CHILD NEUROLOGY 2022. [DOI: 10.26815/acn.2022.00045] [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
|
14
|
Yang Y, Zeng Q, Cheng M, Niu X, Xiangwei W, Gong P, Li W, Ma J, Zhang X, Yang X, Yang Z, Sun D, Zhou S, Liao J, Jiang Y, Zhang Y. GABRB3-related epilepsy: novel variants, clinical features and therapeutic implications. J Neurol 2022; 269:2649-2665. [PMID: 34698933 DOI: 10.1007/s00415-021-10834-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 09/28/2021] [Accepted: 09/29/2021] [Indexed: 02/08/2023]
Abstract
OBJECTIVE This study aimed to comprehensively examine the genetic and phenotypic aspects of GABRB3-related epilepsy and to explore the potential prospects of personalized medicine. METHODS Genetic testing was conducted in all epilepsy patients without acquired factors for epilepsy. Through the collaboration of multicenter in China, we analyzed the genotype-phenotype correlation and antiepileptic therapy of 26 patients with GABRB3-related epilepsy. RESULTS Thirteen GABRB3 variants were novel, and 25 were de novo. The seizure onset age ranged from 1 to 21Â months (median age 3.75Â months). Seizure types predominated including focal seizures (92.3%), generalized tonic-clonic seizures (23.1%), and epileptic spasms (15.4%). Clinical features included cluster seizures (80.8%), fever sensitivity (53.8%), and developmental delay (96.2%). Neuroimaging was abnormal in 10 patients, including dysplasia of the cerebral cortex, dysplasia of the frontal and temporal cortex, delayed myelination, and corpus callosum dysplasia. Eleven patients were diagnosed with developmental and epileptic encephalopathy (DEE), four with West syndrome, three with epilepsy of infancy with migrating focal seizures (EIMFS), one with epilepsy with myoclonic-atonic seizures (EMAS), one with Dravet syndrome, and one with febrile seizures plus (FS+). Seizures were controlled in 57.7% of patients by valproate, levetiracetam, or perampanel in the majority. CONCLUSIONS The clinical features of GABRB3-related epilepsy included seizure onset in early infancy, cluster seizures and fever sensitivity. Most patients manifest severe epilepsy phenotypes. Valproate, levetiracetam and perampanel seem to have positive effects on seizure control for patients with GABRB3 variants.
Collapse
Affiliation(s)
- Ying Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Qi Zeng
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, 518038, China
| | - Miaomiao Cheng
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Xueyang Niu
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Wenshu Xiangwei
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Pan Gong
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Wenhui Li
- Department of Neurology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, 201102, China
| | - Jiehui Ma
- Department of Neurology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430015, China
| | - Xiaoli Zhang
- Department of Pediatrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Dan Sun
- Department of Neurology, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430015, China
| | - Shuizhen Zhou
- Department of Neurology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, 201102, China
| | - Jianxiang Liao
- Department of Neurology, Shenzhen Children's Hospital, Shenzhen, 518038, China
| | - Yuwu Jiang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, 100034, China.
| |
Collapse
|
15
|
Simkin D, Ambrosi C, Marshall KA, Williams LA, Eisenberg J, Gharib M, Dempsey GT, George AL, McManus OB, Kiskinis E. 'Channeling' therapeutic discovery for epileptic encephalopathy through iPSC technologies. Trends Pharmacol Sci 2022; 43:392-405. [PMID: 35427475 PMCID: PMC9119009 DOI: 10.1016/j.tips.2022.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/26/2022] [Accepted: 03/01/2022] [Indexed: 12/16/2022]
Abstract
Induced pluripotent stem cell (iPSC) and gene editing technologies have revolutionized the field of in vitro disease modeling, granting us access to disease-pertinent human cells of the central nervous system. These technologies are particularly well suited for the study of diseases with strong monogenic etiologies. Epilepsy is one of the most common neurological disorders in children, with approximately half of all genetic cases caused by mutations in ion channel genes. These channelopathy-associated epilepsies are clinically diverse, mechanistically complex, and hard to treat. Here, we review the genetic links to epilepsy, the opportunities and challenges of iPSC-based approaches for developing in vitro models of channelopathy-associated disorders, the available tools for effective phenotyping of iPSC-derived neurons, and discuss the potential therapeutic approaches for these devastating diseases.
Collapse
Affiliation(s)
- Dina Simkin
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | | | - Kelly A Marshall
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | | | - Jordyn Eisenberg
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Mennat Gharib
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | | | - Alfred L George
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | | | - Evangelos Kiskinis
- The Ken & Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Simpson Querrey Institute, Northwestern University, Chicago, IL 60611, USA; Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
| |
Collapse
|
16
|
Hieu NLT, Thu NTM, Ngan LTA, Van LTK, Huy DP, Linh PTT, Mai NTQ, Hien HTD, Hang DTT. Genetic analysis using targeted exome sequencing of 53 Vietnamese children with developmental and epileptic encephalopathies. Am J Med Genet A 2022; 188:2048-2060. [PMID: 35365919 DOI: 10.1002/ajmg.a.62741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 01/14/2022] [Accepted: 03/13/2022] [Indexed: 11/07/2022]
Abstract
Developmental and epileptic encephalopathies (DEE) refers to a group of rare and severe neurodevelopmental disorders where genetic etiologies can play a major role. This study aimed to elucidate the genetic etiologies of a cohort of 53 Vietnamese patients with DEE. All patients were classified into known electroclinical syndromes where possible. Exome sequencing (ES) followed by a targeted analysis on 294 DEE-related genes was then performed. Patients with identified causative variants were followed for 6 months to determine the impact of genetic testing on their treatment. The diagnostic yield was 38.0% (20/53), which was significantly higher in the earlier onset group (<12 months) than in the later onset group (≥12 months). The 19 identified variants belonged to 11 genes with various cellular functions. Genes encoding ion channels especially sodium voltage-gated channel were the most frequently involved. Most variants were missense variants and located in key protein functional domains. Four variants were novel and four had been reported previously but in different phenotypes. Within 6 months of further follow-up, treatment changes were applied for six patients based on the identified disease-causing variants, with five patients showing a positive impact. This is the first study in Vietnam to analyze the genetics of DEE. This study confirms the strong involvement of genetic etiologies in DEE, especially early onset DEE. The study also contributes to clarify the genotype-phenotype correlations of DEE and highlights the efficacy of targeted ES in the diagnosis and treatment of DEE.
Collapse
Affiliation(s)
- Nguyen Le Trung Hieu
- Neurology Department, Children Hospital 2, Ho Chi Minh City, Vietnam.,University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam
| | | | - Le Tran Anh Ngan
- Neurology Department, Children Hospital 2, Ho Chi Minh City, Vietnam
| | - Le Thi Khanh Van
- Neurology Department, Children Hospital 2, Ho Chi Minh City, Vietnam
| | - Do Phuoc Huy
- Medical Genetics Institute, Ho Chi Minh City, Vietnam
| | - Pham Thi Truc Linh
- Functional Genomic Unit, DNA Medical Technology Company, Ho Chi Minh City, Vietnam
| | - Nguyen Thi Quynh Mai
- Research Center for Genetics and Reproductive Health, School of Medicine, Vietnam National University, Ho Chi Minh City, Vietnam
| | - Huynh Thi Dieu Hien
- Research Center for Genetics and Reproductive Health, School of Medicine, Vietnam National University, Ho Chi Minh City, Vietnam
| | - Do Thi Thu Hang
- Research Center for Genetics and Reproductive Health, School of Medicine, Vietnam National University, Ho Chi Minh City, Vietnam
| |
Collapse
|
17
|
Ding J, Li X, Tian H, Wang L, Guo B, Wang Y, Li W, Wang F, Sun T. SCN1A Mutation-Beyond Dravet Syndrome: A Systematic Review and Narrative Synthesis. Front Neurol 2022; 12:743726. [PMID: 35002916 PMCID: PMC8739186 DOI: 10.3389/fneur.2021.743726] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 11/29/2021] [Indexed: 12/28/2022] Open
Abstract
Background:SCN1A is one of the most common epilepsy genes. About 80% of SCN1A gene mutations cause Dravet syndrome (DS), which is a severe and catastrophic epileptic encephalopathy. More than 1,800 mutations have been identified in SCN1A. Although it is known that SCN1A is the main cause of DS and genetic epilepsy with febrile seizures plus (GEFS+), there is a dearth of information on the other related diseases caused by mutations of SCN1A. Objective: The aim of this study is to systematically review the literature associated with SCN1A and other non-DS-related disorders. Methods: We searched PubMed and SCOPUS for all the published cases related to gene mutations of SCN1A until October 20, 2021. The results reported by each study were summarized narratively. Results: The PubMed and SCOPUS search yielded 2,889 items. A total of 453 studies published between 2005 and 2020 met the final inclusion criteria. Overall, 303 studies on DS, 93 on GEFS+, three on Doose syndrome, nine on the epilepsy of infancy with migrating focal seizures (EIMFS), six on the West syndrome, two on the Lennox–Gastaut syndrome (LGS), one on the Rett syndrome, seven on the nonsyndromic epileptic encephalopathy (NEE), 19 on hemiplegia migraine, six on autism spectrum disorder (ASD), two on nonepileptic SCN1A-related sudden deaths, and two on the arthrogryposis multiplex congenital were included. Conclusion: Aside from DS, SCN1A also causes other epileptic encephalopathies, such as GEFS+, Doose syndrome, EIMFS, West syndrome, LGS, Rett syndrome, and NEE. In addition to epilepsy, hemiplegic migraine, ASD, sudden death, and arthrogryposis multiplex congenital can also be caused by mutations of SCN1A.
Collapse
Affiliation(s)
- Jiangwei Ding
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
| | - Xinxiao Li
- Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Haiyan Tian
- Department of Neurology, First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Lei Wang
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Baorui Guo
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
| | - Yangyang Wang
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Wenchao Li
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Feng Wang
- Department of Neurosurgery, The First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Tao Sun
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China.,Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
| |
Collapse
|
18
|
Shin IJ, Sohn SY, Kim SY, Joo IS. A Novel KCNA1 Variant Manifesting as Persistent Limb Myokymia Without Episodic Ataxia. J Clin Neurol 2022; 18:235-237. [PMID: 35274848 PMCID: PMC8926766 DOI: 10.3988/jcn.2022.18.2.235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/17/2021] [Accepted: 12/20/2021] [Indexed: 11/17/2022] Open
Affiliation(s)
- In Ja Shin
- Department of Neurology, Ajou University Medical Center, Ajou University School of Medicine, Suwon, Korea
| | - Sung-Yeon Sohn
- Department of Neurology, Ajou University Medical Center, Ajou University School of Medicine, Suwon, Korea
| | - Shin Yeop Kim
- Department of Neurology, Ajou University Medical Center, Ajou University School of Medicine, Suwon, Korea
| | - In Soo Joo
- Department of Neurology, Ajou University Medical Center, Ajou University School of Medicine, Suwon, Korea
| |
Collapse
|
19
|
Negraes PD, Trujillo CA, Yu NK, Wu W, Yao H, Liang N, Lautz JD, Kwok E, McClatchy D, Diedrich J, de Bartolome SM, Truong J, Szeto R, Tran T, Herai RH, Smith SEP, Haddad GG, Yates JR, Muotri AR. Altered network and rescue of human neurons derived from individuals with early-onset genetic epilepsy. Mol Psychiatry 2021; 26:7047-7068. [PMID: 33888873 PMCID: PMC8531162 DOI: 10.1038/s41380-021-01104-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 03/22/2021] [Accepted: 04/06/2021] [Indexed: 02/02/2023]
Abstract
Early-onset epileptic encephalopathies are severe disorders often associated with specific genetic mutations. In this context, the CDKL5 deficiency disorder (CDD) is a neurodevelopmental condition characterized by early-onset seizures, intellectual delay, and motor dysfunction. Although crucial for proper brain development, the precise targets of CDKL5 and its relation to patients' symptoms are still unknown. Here, induced pluripotent stem cells derived from individuals deficient in CDKL5 protein were used to generate neural cells. Proteomic and phosphoproteomic approaches revealed disruption of several pathways, including microtubule-based processes and cytoskeleton organization. While CDD-derived neural progenitor cells have proliferation defects, neurons showed morphological alterations and compromised glutamatergic synaptogenesis. Moreover, the electrical activity of CDD cortical neurons revealed hyperexcitability during development, leading to an overly synchronized network. Many parameters of this hyperactive network were rescued by lead compounds selected from a human high-throughput drug screening platform. Our results enlighten cellular, molecular, and neural network mechanisms of genetic epilepsy that could ultimately promote novel therapeutic opportunities for patients.
Collapse
Affiliation(s)
- Priscilla D Negraes
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Cleber A Trujillo
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA.
| | - Nam-Kyung Yu
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Wei Wu
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Hang Yao
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Nicholas Liang
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Jonathan D Lautz
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, USA
| | - Ellius Kwok
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Daniel McClatchy
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Jolene Diedrich
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Justin Truong
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Ryan Szeto
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Timothy Tran
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
| | - Roberto H Herai
- Experimental Multiuser Laboratory, Graduate Program in Health Sciences, School of Medicine, PontifĂcia Universidade CatĂłlica do Paraná, Curitiba, Paraná, Brazil
| | - Stephen E P Smith
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, USA
| | - Gabriel G Haddad
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Alysson R Muotri
- Department of Pediatrics, University of California San Diego, La Jolla, CA, USA.
- Kavli Institute for Brain and Mind, University of California San Diego, La Jolla, CA, USA.
- Center for Academic Research and Training in Anthropogeny (CARTA), La Jolla, CA, USA.
| |
Collapse
|
20
|
Trollmann R. Neuromonitoring bei zerebralen Anfällen im Neugeborenenalter – Chancen und Herausforderungen. KLIN NEUROPHYSIOL 2021. [DOI: 10.1055/a-1438-1828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Angesichts der vielen Kinder mit neonatalen Risikofaktoren für erworbene ZNS-Läsionen und zerebrale Anfälle ist das EEG zunehmend relevant für eine optimierte Diagnostik und Therapieüberwachung 1
2. Folgender Artikel gibt einen Überblick über Besonderheiten des neonatalen EEG und über aktuelle Empfehlungen zum Stellenwert des Langzeit-EEG-Monitorings bei neonatalen Anfällen und epileptischen Enzephalopathien im Früh- und Neugeborenalter.
Collapse
|
21
|
Liu X, Shen Q, Zheng G, Guo H, Lu X, Wang X, Yang X, Cao Z, Chen J. Gene and Phenotype Expansion of Unexplained Early Infantile Epileptic Encephalopathy. Front Neurol 2021; 12:633637. [PMID: 34163418 PMCID: PMC8215605 DOI: 10.3389/fneur.2021.633637] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/14/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: The genetic aetiology of epileptic encephalopathy (EE) is growing rapidly based on next generation sequencing (NGS) results. In this single-centre study, we aimed to investigate a cohort of Chinese children with early infantile epileptic encephalopathy (EIEE). Methods: NGS was performed on 50 children with unexplained EIEE. The clinical profiles of children with pathogenic variants were characterised and analysed in detail. Conservation analysis and homology modelling were performed to predict the impact of STXBP1 variant on the protein structure. Results: Pathogenic variants were identified in 17 (34%) of 50 children. Sixteen variants including STXBP1 (n = 2), CDKL5 (n = 2), PAFAH1B1, SCN1A (n = 9), SCN2A, and KCNQ2 were de novo, and one (PIGN) was a compound heterozygous variant. The phenotypes of the identified genes were broadened. PIGN phenotypic spectrum may include EIEE. The STXBP1 variants were predicted to affect protein stability. Significance: NGS is a useful diagnostic tool for EIEE and contributes to expanding the EIEE-associated genotypes. Early diagnosis may lead to precise therapeutic interventions and can improve the developmental outcome.
Collapse
Affiliation(s)
- Xianyu Liu
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Qiyang Shen
- Department of Pediatric Surgery, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Guo Zheng
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Hu Guo
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaopeng Lu
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaoyu Wang
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Xiao Yang
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Zixuan Cao
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| | - Jing Chen
- Department of Neurology, Children's Hospital of Nanjing Medical University, Nanjing, China
| |
Collapse
|
22
|
Fontana A, Consentino MC, Motta M, Costanza G, Lo Bianco M, Marino S, Falsaperla R, Praticò AD. Syntaxin Binding Protein 1 Related Epilepsies. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727259] [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
AbstractSyntaxin binding protein 1 (STXBP1), commonly known as MUNC18–1, is a member of SEC1 family membrane trafficking proteins; their function consists in controlling the soluble N-ethylmaleimide-sensitive factor attachment protein receptors complex assembly, making them essentials regulators of vesicle fusion. The precise function and molecular mechanism through which Munc18–1 contributes to neurotransmitter releasing is not entirely understood, but several evidences suggest its probable role in exocytosis. In 2008, heterozygous de novo mutations in neuronal protein Munc18–1 were first referred as a cause of Ohtahara syndrome development. Currently, a wide examination of the published data proved that 3.1% of patients with severe epilepsy carry a pathogenic de novo mutation including STXBP1 and approximately 10.2% of early onset epileptic encephalopathy is due to an aberrant STXBP1 form codified by the mutated gene. STXBP1 mutations can be associated to a wide clinical heterogeneity. All affected individuals show developmental delay and approximately the 95% of cases have seizures and early onset epileptic encephalopathy, characterized by infantile spasms as the main consistent feature. Burst suppression pattern and hypsarrhythmia are the most frequent EEG anomalies. Other neuronal disorders include Rett syndrome and behavioral and movement disorders. Mild dysmorphic features have been detected in a small number of cases. No genotype–phenotype correlation has been reported. Management of STXBP1 encephalopathy requires a multidisciplinary approach, including epilepsy control and neurological rehabilitation. About 25% of patients are refractory to standard therapy. A single or combined antiepileptic drugs may be required. Several studies described vigabatrin, valproic acid, levetiracetam, topiramate, clobazam, and oxcarbazepine as effective in seizure control. Lamotrigine, zonisamide, and phenobarbital are also commonly used. To date, it remains unclear which therapy is the most effective. Severe morbidity and high mortality are inevitable consequences in some of these patients.
Collapse
Affiliation(s)
- Alessandra Fontana
- Pediatrics Postgraduate Residency Program, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Maria Chiara Consentino
- Pediatrics Postgraduate Residency Program, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Milena Motta
- Pediatrics Postgraduate Residency Program, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Giuseppe Costanza
- Pediatrics Postgraduate Residency Program, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Manuela Lo Bianco
- Pediatrics Postgraduate Residency Program, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
| | - Simona Marino
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” 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
| | - 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
| |
Collapse
|
23
|
Boets S, Johannesen KM, Destree A, Manti F, Ramantani G, Lesca G, Vercueil L, Koenig MK, Striano P, Møller RS, Cooper E, Weckhuysen S. Adult phenotype of KCNQ2 encephalopathy. J Med Genet 2021; 59:528-535. [PMID: 33811133 DOI: 10.1136/jmedgenet-2020-107449] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 03/02/2021] [Accepted: 03/10/2021] [Indexed: 11/03/2022]
Abstract
BACKGROUND Pathogenic KCNQ2 variants are a frequent cause of developmental and epileptic encephalopathy. METHODS We recruited 13 adults (between 18 years and 45 years of age) with KCNQ2 encephalopathy and reviewed their clinical, EEG, neuroimaging and treatment history. RESULTS While most patients had daily seizures at seizure onset, seizure frequency declined or remitted during childhood and adulthood. The most common seizure type was tonic seizures (early) infancy, and tonic-clonic and focal impaired awareness seizures later in life. Ten individuals (77%) were seizure-free at last follow-up. In 38% of the individuals, earlier periods of seizure freedom lasting a minimum of 2 years followed by seizure recurrence had occurred. Of the 10 seizure-free patients, 4 were receiving a single antiseizure medication (ASM, carbamazepine, lamotrigine or levetiracetam), and 2 had stopped taking ASM. Intellectual disability (ID) ranged from mild to profound, with the majority (54%) of individuals in the severe category. At last contact, six individuals (46%) remained unable to walk independently, six (46%) had limb spasticity and four (31%) tetraparesis/tetraplegia. Six (46%) remained non-verbal, 10 (77%) had autistic features/autism, 4 (31%) exhibited aggressive behaviour and 4 (31%) destructive behaviour with self-injury. Four patients had visual problems, thought to be related to prematurity in one. Sleep problems were seen in six (46%) individuals. CONCLUSION Seizure frequency declines over the years and most patients are seizure-free in adulthood. Longer seizure-free periods followed by seizure recurrence are common during childhood and adolescence. Most adult patients have severe ID. Motor, language and behavioural problems are an issue of continuous concern.
Collapse
Affiliation(s)
- Stephanie Boets
- Neurology Department, University Hospital Antwerp, Antwerp, Belgium
| | - Katrine M Johannesen
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Centre Filadelfia, Dianalund, Denmark.,Institute for Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Anne Destree
- Department of Human Genetics, Institute of Pathology and Genetics, Gosselies, Belgium
| | - Filippo Manti
- Department of Human Neuroscience, University of Rome La Sapienza, Roma, Lazio, Italy
| | - Georgia Ramantani
- Department of Neuropediatrics, University Children's Hospital, Zurich, Switzerland
| | - Gaetan Lesca
- Department of Genetics, University Hospitals of Lyon, Lyon, France.,Neuroscience Research Center, Claude Bernard Lyon I University, Lyon, France
| | - Laurent Vercueil
- Grenoble Institute of Neurosciences (GIN), University Grenoble Alpes, La Tronche, France
| | - Mary Kay Koenig
- Department of Pediatrics, University of Texas McGovern Medical School, Houston, Texas, USA
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, "G Gaslini" Institute, Genova, Italy.,Pediatric Neurology and Muscular Diseases Unit, IRCCS' G Gaslini" Institute, Genova, Italy
| | - Rikke Steensbjerre Møller
- Department of Epilepsy Genetics and Personalized Treatment, The Danish Epilepsy Centre Filadelfia, Dianalund, Denmark.,Institute for Regional Health Research, University of Southern Denmark, Odense, Denmark
| | - Edward Cooper
- Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
| | - Sarah Weckhuysen
- Neurology Department, University Hospital Antwerp, Antwerp, Belgium .,Applied & Translational Neurogenomics Group, VIB-Center for Molecular Neurology, VIB, Antwerp, Belgium.,Translational Neuroscience Group, University of Antwerp, Antwerp, Belgium
| |
Collapse
|
24
|
Trollmann R. Neuromonitoring in Neonatal-Onset Epileptic Encephalopathies. Front Neurol 2021; 12:623625. [PMID: 33603712 PMCID: PMC7884638 DOI: 10.3389/fneur.2021.623625] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 01/12/2021] [Indexed: 12/31/2022] Open
Abstract
Considering the wide spectrum of etiologies of neonatal-onset epileptic encephalopathies (EE) and their unfavorable consequences for neurodevelopmental prognoses, neuromonitoring at-risk neonates is increasingly important. EEG is highly sensitive for early identification of electrographic seizures and abnormal background activity. Amplitude-integrated EEG (aEEG) is recommended as a useful bedside monitoring method but as a complementary tool because of methodical limitations. It is of special significance in monitoring neonates with acute symptomatic as well as structural, metabolic and genetic neonatal-onset EE, being at high risk of electrographic-only and prolonged seizures. EEG/aEEG monitoring is established as an adjunctive tool to confirm perinatal hypoxic-ischemic encephalopathy (HIE). In neonates with HIE undergoing therapeutic hypothermia, burst suppression pattern is associated with good outcomes in about 40% of the patients. The prognostic specificity of EEG/aEEG is lower compared to cMRI. As infants with HIE may develop seizures after cessation of hypothermia, recording for at least 24 h after the last seizure is recommended. Progress in the identification of genetic etiology of neonatal EE constantly increases. However, presently, no specific EEG changes indicative of a genetic variant have been characterized, except for individual variants associated with typical EEG patterns (e.g., KCNQ2, KCNT1). Long-term monitoring studies are necessary to define and classify electro-clinical patterns of neonatal-onset EE.
Collapse
Affiliation(s)
- Regina Trollmann
- Department of Pediatrics and Pediatric Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
25
|
Chow CK, Luk HM, Wong SN. KCNQ2 Encephalopathy and Responsiveness to Pyridoxal-5'-Phosphate. J Pediatr Genet 2020; 12:90-94. [PMID: 36684546 PMCID: PMC9848766 DOI: 10.1055/s-0040-1721384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/25/2020] [Indexed: 01/25/2023]
Abstract
KCNQ2 mutations encompass a wide range of phenotypes, ranging from benign familial neonatal seizure to a clinical spectrum of early-onset epileptic encephalopathy that occurs in the early neonatal period. We report an infant with KCNQ2 encephalopathy presenting as neonatal seizure, initially controlled by two anticonvulsants. Electroencephalogram (EEG) showed repetitive multifocal epileptiform discharges, which remained similar after administration of intravenous pyridoxine injection. Seizure recurred at the age of 3 months preceded by an episode of minor viral infection, which occurred multiple times per day. No significant change in seizure frequency was observed after 5-day oral pyridoxine trial, but subsequently, there was dramatic seizure improvement with oral pyridoxal-5'-phosphate (PLP). We hope to alert clinicians that in patients with neonatal epileptic encephalopathy, particularly with known KCNQ2 mutations, intravenous injection of pyridoxine (preferably with EEG monitoring), followed by both oral trial of pyridoxine and PLP should be considered. KCNQ2 mutations should also be considered in vitamin B6-responsive patients.
Collapse
Affiliation(s)
- Chit Kwong Chow
- Department of Paediatrics and Adolescent Medicine, United Christian Hospital, HKSAR, Hong Kong,Address for correspondence Chit Kwong Chow, MBBS (HK), FHKC (Paed), FHKAM (Paediatrics) Department of Paediatrics and Adolescent Medicine, United Christian Hospital130 Hip Wo Street, Kwun Tong, Kowloon, HKSARHong Kong
| | - Ho Ming Luk
- Clinical Genetic Service, Department of Health, HKSAR, Hong Kong
| | - Suet Na Wong
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, HKSAR, Hong Kong
| |
Collapse
|
26
|
Kwak N, Lee YJ, Kim D, Hwang SK, Kwon S, Lee EJ. KCNQ2 Encephalopathy Showing a Distinct Ictal Amplitude-Integrated Electroencephalographic Pattern. NEONATAL MEDICINE 2020. [DOI: 10.5385/nm.2020.27.4.202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
|