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Fasaludeen A, McTague A, Jose M, Banerjee M, Sundaram S, Madhusoodanan UK, Radhakrishnan A, Menon RN. Genetic variant interpretation for the neurologist - A pragmatic approach in the next-generation sequencing era in childhood epilepsy. Epilepsy Res 2024; 201:107341. [PMID: 38447235 DOI: 10.1016/j.eplepsyres.2024.107341] [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: 11/27/2023] [Revised: 02/14/2024] [Accepted: 02/29/2024] [Indexed: 03/08/2024]
Abstract
Genetic advances over the past decade have enhanced our understanding of the genetic landscape of childhood epilepsy. However a major challenge for clinicians ha been understanding the rationale and systematic approach towards interpretation of the clinical significance of variant(s) detected in their patients. As the clinical paradigm evolves from gene panels to whole exome or whole genome testing including rapid genome sequencing, the number of patients tested and variants identified per patient will only increase. Each step in the process of variant interpretation has limitations and there is no single criterion which enables the clinician to draw reliable conclusions on a causal relationship between the variant and disease without robust clinical phenotyping. Although many automated online analysis software tools are available, these carry a risk of misinterpretation. This guideline provides a pragmatic, real-world approach to variant interpretation for the child neurologist. The focus will be on ascertaining aspects such as variant frequency, subtype, inheritance pattern, structural and functional consequence with regard to genotype-phenotype correlations, while refraining from mere interpretation of the classification provided in a genetic test report. It will not replace the expert advice of colleagues in clinical genetics, however as genomic investigations become a first-line test for epilepsy, it is vital that neurologists and epileptologists are equipped to navigate this landscape.
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Affiliation(s)
- Alfiya Fasaludeen
- Dept of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India
| | - Amy McTague
- Developmental Neurosciences, UCL Great Ormond Street Institute of Child Health, London, United Kingdom; Department of Neurology, Great Ormond Street Hospital, London, United Kingdom
| | - Manna Jose
- Dept of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India
| | - Moinak Banerjee
- Human Molecular Genetics Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Soumya Sundaram
- Dept of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India
| | - U K Madhusoodanan
- Department of Biochemistry, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India
| | - Ashalatha Radhakrishnan
- Dept of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India
| | - Ramshekhar N Menon
- Dept of Neurology, Sree Chitra Tirunal Institute for Medical Sciences & Technology (SCTIMST), Thiruvananthapuram, Kerala, India.
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Fang H, Hu W, Kang Q, Kuang X, Wang L, Zhang X, Liao H, Yang L, Yang H, Jiang Z, Wu L. Clinical characteristics and genetic analysis of pediatric patients with sodium channel gene mutation-related childhood epilepsy: a review of 94 patients. Front Neurol 2023; 14:1310419. [PMID: 38174099 PMCID: PMC10764033 DOI: 10.3389/fneur.2023.1310419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 11/27/2023] [Indexed: 01/05/2024] Open
Abstract
Objective This study aimed to examine the clinical and gene-mutation characteristics of pediatric patients with sodium channel gene mutation-related childhood epilepsy and to provide a basis for precision treatment and genetic counseling. Methods The clinical data from 94 patients with sodium channel gene mutation-related childhood epilepsy who were treated at Hunan Children's Hospital from August 2012 to December 2022 were retrospectively evaluated, and the clinical characteristics, gene variants, treatment, and follow-up status were analyzed and summarized. Results Our 94 pediatric patients with sodium channel gene variant-related childhood epilepsy comprised 37 girls and 57 boys. The age of disease onset ranged from 1 day to 3 years. We observed seven different sodium channel gene variants, and 55, 14, 9, 6, 6, 2, and 2 patients had SCNlA, SCN2A, SCN8A, SCN9A, SCN1B, SCN11A, and SCN3A variants, respectively. We noted that 52 were reported variants and 42 were novel variants. Among all gene types, SCN1A, SCN2A, and SCN8A variants were associated with an earlier disease onset age. With the exception of the SCN1B, the other six genes were associated with clustering seizures. Except for variants SCN3A and SCN11A, some patients with other variants had status epilepticus (SE). The main diagnosis of children with SCN1A variants was Dravet syndrome (DS) (72.7%), whereas patients with SCN2A and SCN8A variants were mainly diagnosed with various types of epileptic encephalopathy, accounting for 85.7% (12 of 14) and 88.9% (8 of 9) respectively. A total of five cases of sudden unexpected death in epilepsy (SUDEP) occurred in patients with SCN1A, SCN2A, and SCN8A variants. The proportion of benign epilepsy in patients with SCN9A, SCN11A, and SCN1B variants was relatively high, and the epilepsy control rate was higher than the rate of other variant types. Conclusion Sodium channel gene variants involve different epileptic syndromes, and the treatment responses also vary. We herein reported 42 novel variants, and we are also the first ever to report two patients with SCN11A variants, thereby increasing the gene spectrum and phenotypic profile of sodium channel dysfunction. We provide a basis for precision treatment and prognostic assessment.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Liwen Wu
- Neurology Department, Hunan Children's Hospital, Changsha, China
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Atlı E, Gürkan H, Güldiken B, Eker D, Yalçıntepe S, Demir S, Atlı Eİ. Investigation of the Genetic Etiology in Idiopathic Generalized Epileptic Disorders by Targeted Next-generation Sequencing Technique. Balkan Med J 2023; 40:13-20. [PMID: 36374051 PMCID: PMC9874255 DOI: 10.4274/balkanmedj.galenos.2022.2022-7-55] [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: 11/16/2022] Open
Abstract
Background Idiopathic generalized epilepsy is the most common group of epilepsy disorders in children and adolescents. Various types of genetic abnormality were identified among the hereditary factors that explain epilepsy. Aims To determine the variations in the etiopathogenesis, treatment protocol planning, and prognosis of idiopathic generalized epilepsy using the next-generation sequencing method. Study Design A cross-sectional study. Methods This study included 32 patients with idiopathic generalized epilepsy. Genomic DNA was obtained from peripheral venous blood samples taken from the patients. A total of 18 genes encoding ion channel subunits that are involved in monogenic disorders and are associated with idiopathic generalized epilepsy were included. The targeted custom next-generation sequencing panel was designed to cover all coding exons and all exon/intron splice site regions of 18 genes. Results We detected 9 (28%) variations, including 1 likely pathogenic (a variant in the SCN1A gene) and 8 of unknown clinical significance (2 in the CLCN2 genes, GABBR2, SCN1B, SLC2A1, SLC4A10 genes, and 2 in the TBC1D24 gene). Conclusion Study results should be supported by functional advanced studies, with increased existing knowledge in the relevant variations.
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Affiliation(s)
- Engin Atlı
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Hakan Gürkan
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Babürhan Güldiken
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Damla Eker
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Sinem Yalçıntepe
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Selma Demir
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey
| | - Emine İkbal Atlı
- Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey,* Address for Correspondence: Department of Medical Genetics, Faculty of Medicine Trakya University, Edirne, Turkey E-mail:
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Alghamdi MA, Al-Eitan LN, Asiri A, Rababa'h DM, Alqahtani SA, Aldarami MS, Alsaeedi MA, Almuidh RS, Alzahrani AA, Sakah AH, El Nashar EM, Otaif MY, Abdel Ghaffar NF. Association of sodium voltage-gated channel genes polymorphisms with epilepsy risk and prognosis in the Saudi population. Ann Med 2022; 54:1938-1951. [PMID: 35801810 PMCID: PMC9367647 DOI: 10.1080/07853890.2022.2096257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Epilepsy is a heterogeneous complex condition that involve the human brain. Genetic predisposition to epilepsy is a fundamental factor of the disorder aetiology. The sodium voltage-gated channel (SCN) genes variants are critical biomarker for the epilepsy development and progression. In this study, we aimed to investigate the association of several SNCs genetic polymorphisms with epilepsy risk and their intrudance of the disease prognosis. METHODS Blood samples were withdrawn from 296 Epilepsy patients in addition to 293 healthy matched participants prior to DNA extraction. PCR-sequencing was used for genotyping analysis. Genotyping outputs were then statistically analysed for genotype/phenotype evaluation. RESULTS Within SCN1A gene we found that the rs6432861 (p = 0.014) was in correlation with the risk of epilepsy. In addition, both rs4667485 and rs1469649 of SCN2A gene were significantly correlated to epilepsy risk for both allelic (4e-4 and 1e-3) and genotypic (1e-3 and 5e-3). Moreover, the haplotype analysis showed that the GATGCTCGGTTTCGCTACGCA haplotype of SCN2A gene was significantly related to epilepsy increased risk, p = 6e-3, OR (CI) = 2.02 (1.23-3.31). In relevant to our finding, many of the investigated SCNs variants in the current study were related to several clinical features of epilepsy. CONCLUSION In light of our results, we infer that SCN genes polymorphisms are strong candidates for epilepsy development and progression. Furthermore, these variant are essential for the disorder prognosis and medications outcomes.Key MessagesGenetic polymorphisms of sodium channels SCN1A, SCN2A and SCN3A were found to be associated with the risk of epilepsy.SCN1B polymorphisms were found to be correlated to epilepsy reduced risk.SCNs variants are involved in the epilepsy prognosis and response to treatment.
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Affiliation(s)
- Mansour A Alghamdi
- Department of Anatomy, College of Medicine, King Khalid University, Abha, Saudi Arabia.,Genomics and Personalized Medicine Unit, College of Medicine, King Khalid University, Abha, Saudi Arabia
| | - Laith N Al-Eitan
- Department of Applied Biological Sciences, Jordan University of Science and Technology, Irbid, Jordan.,Department of Biotechnology and Genetic Engineering, Jordan University of Science and Technology, Irbid, Jordan
| | - Ashwag Asiri
- Department of Child Health, College of Medicine, King Khalid University, Abha, Saudi Arabia
| | - Doaa M Rababa'h
- Department of Applied Biological Sciences, Jordan University of Science and Technology, Irbid, Jordan
| | - Sultan A Alqahtani
- Neurology Department, Neuroscience Centre, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Mohammed S Aldarami
- Neurology Department, Neuroscience Centre, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Manar A Alsaeedi
- Neurology Department, Neuroscience Centre, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Raghad S Almuidh
- Neurology Department, Neuroscience Centre, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Abdulbari A Alzahrani
- Neurology Department, Neuroscience Centre, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Ahmad H Sakah
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Eman Mohamad El Nashar
- Department of Anatomy, College of Medicine, King Khalid University, Abha, Saudi Arabia.,Department of Histology and Cell Biology, Faculty of Medicine, Benha University, Benha, Egypt
| | - Mansour Y Otaif
- Department of Pediatric, Neurology section, Abha Maternity and Childern Hospital, Abha, Saudi Arabia
| | - Nawal F Abdel Ghaffar
- Neurology Department, Kasr Al Ainy Hospital, Faculty of Medicine, Cairo University, Giza, Egypt.,Neurology Department, Aseer Central Hospital, Abha, Saudi Arabia
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Zhu Z, Bolt E, Newmaster K, Osei-Bonsu W, Cohen S, Cuddapah VA, Gupta S, Paudel S, Samanta D, Dang LT, Carney PR, Naik S. SCN1B Genetic Variants: A Review of the Spectrum of Clinical Phenotypes and a Report of Early Myoclonic Encephalopathy. CHILDREN (BASEL, SWITZERLAND) 2022; 9:1507. [PMID: 36291443 PMCID: PMC9600564 DOI: 10.3390/children9101507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 11/06/2022]
Abstract
Background: Pathogenic variants in SCN1B, the gene encoding voltage-gated sodium channel b1/b1B subunits are associated with a spectrum of epileptic disorders. This study describes a child with early myoclonic encephalopathy and a compound heterozygous variant in the SCN1B gene (p.Arg85Cys and c.3G>C/p.Met1), along with the child’s clinical response to anti-seizure medications (ASMs) and the ketogenic diet. We reviewed the current clinical literature pertinent to SCN1B-related epilepsy. Methods: We described the evaluation and management of a patient with SCN1B-related developmental and epileptic encephalopathy (DEE). We used the Medline and Pubmed databases to review the various neurological manifestations associated with SCN1B genetic variants, and summarize the functional studies performed on SCN1B variants. Results: We identified 20 families and six individuals (including the index case described herein) reported to have SCN1B-related epilepsy. Individuals with monoallelic pathogenic variants in SCN1B often present with genetic epilepsy with febrile seizures plus (GEFS+), while those with biallelic pathogenic variants may present with developmental and epileptic encephalopathy (DEE). Individuals with DEE present with seizures of various semiologies (commonly myoclonic seizures) and status epilepticus at early infancy and are treated with various antiseizure medications. In our index case, adjunctive fenfluramine was started at 8 months of age at 0.2 mg/kg/day with gradual incremental increases to the final dose of 0.7 mg/kg/day over 5 weeks. Fenfluramine was effective in the treatment of seizures, resulting in a 50% reduction in myoclonic seizures, status epilepticus, and generalized tonic-clonic seizures, as well as a 70−90% reduction in focal seizures, with no significant adverse effects. Following the initiation of fenfluramine at eight months of age, there was also a 50% reduction in the rate of hospitalizations. Conclusions: SCN1B pathogenic variants cause epilepsy and neurodevelopmental impairment with variable expressivity and incomplete penetrance. The severity of disease is associated with the zygosity of the pathogenic variants. Biallelic variants in SCN1B can result in early myoclonic encephalopathy, and adjunctive treatment with fenfluramine may be an effective treatment for SCN1B-related DEE. Further research on the efficacy and safety of using newer ASMs, such as fenfluramine in patients under the age of 2 years is needed.
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Affiliation(s)
- Zahra Zhu
- College of Medicine, Penn State University, Hershey, PA 17033, USA
| | - Elizabeth Bolt
- College of Medicine, Penn State University, Hershey, PA 17033, USA
| | - Kyra Newmaster
- College of Medicine, Penn State University, Hershey, PA 17033, USA
| | - Wendy Osei-Bonsu
- College of Medicine, Penn State University, Hershey, PA 17033, USA
| | - Stacey Cohen
- Epilepsy Neurogenetics Initiative, Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Vishnu Anand Cuddapah
- Epilepsy Neurogenetics Initiative, Division of Neurology, Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Siddharth Gupta
- Kennedy Krieger Institute, Department of Neurology, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Sita Paudel
- Department of Pediatrics and Neurology, Penn State Health Milton Hershey Medical Center, Hershey, PA 17033, USA
| | - Debopam Samanta
- Division of Pediatric Neurology, Arkansas Children’s Hospital, Little Rock, AR 72202, USA
| | - Louis T. Dang
- Department of Pediatrics, Division of Pediatric Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Paul R. Carney
- Pediatric Neurology Division, University of Missouri Health Care, Columbia, MO 65212, USA
| | - Sunil Naik
- Department of Pediatrics and Neurology, Penn State Health Milton Hershey Medical Center, Hershey, PA 17033, USA
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Ding J, Wang L, Jin Z, Qiang Y, Li W, Wang Y, Zhu C, Jiang S, Xiao L, Hao X, Hu X, Li X, Wang F, Sun T. Do All Roads Lead to Rome? Genes Causing Dravet Syndrome and Dravet Syndrome-Like Phenotypes. Front Neurol 2022; 13:832380. [PMID: 35359639 PMCID: PMC8961694 DOI: 10.3389/fneur.2022.832380] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/26/2022] [Indexed: 11/16/2022] Open
Abstract
Background Dravet syndrome (DS) is a severe epileptic encephalopathy mainly caused by haploinsufficiency of the gene SCN1A, which encodes the voltage-gated sodium channel NaV1. 1 in the brain. While SCN1A mutations are known to be the primary cause of DS, other genes that may cause DS are poorly understood. Several genes with pathogenic mutations result in DS or DS-like phenotypes, which may require different drug treatment approaches. Therefore, it is urgent for clinicians, especially epilepsy specialists to fully understand these genes involved in DS in addition to SCN1A. Particularly for healthcare providers, a deep understanding of these pathogenic genes is useful in properly selecting and adjusting drugs in a more effective and timely manner. Objective The purpose of this study was to identify genes other than SCN1A that may also cause DS or DS-like phenotypes. Methods A comprehensive search of relevant Dravet syndrome and severe myoclonic epilepsy in infancy was performed in PubMed, until December 1, 2021. Two independent authors performed the screening for potentially eligible studies. Disagreements were decided by a third, more professional researcher or by all three. The results reported by each study were narratively summarized. Results A PubMed search yielded 5,064 items, and other sources search 12 records. A total of 29 studies published between 2009 and 2021 met the inclusion criteria. Regarding the included articles, seven studies on PCDH19, three on SCN2A, two on SCN8A, five on SCN1B, two on GABRA1, three on GABRB3, three on GABRG2, and three on STXBP1 were included. Only one study was recorded for CHD2, CPLX1, HCN1 and KCNA2, respectively. It is worth noting that a few articles reported on more than one epilepsy gene. Conclusion DS is not only identified in variants of SCN1A, but other genes such as PCDH19, SCN2A, SCN8A, SCN1B, GABRA1, GABRB3, GABRG2, KCNA2, CHD2, CPLX1, HCN1A, STXBP1 can also be involved in DS or DS-like phenotypes. As genetic testing becomes more widely available, more genes associated with DS and DS-like phenotypes may be identified and gene-based diagnosis of subtypes of phenotypes in this spectrum may improve the management of these diseases in the future.
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Affiliation(s)
- Jiangwei Ding
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Lei Wang
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Zhe Jin
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Yuanyuan Qiang
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
| | - Wenchao Li
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Yangyang Wang
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China
| | - Changliang Zhu
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Shucai Jiang
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Lifei Xiao
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Xiaoyan Hao
- Department of Neurology, First Affiliated Hospital of Zhengzhou Universiy, Zhengzhou, China
| | - Xulei Hu
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Xinxiao Li
- Department of Neurosurgery, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Xinxiao Li
| | - Feng Wang
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Feng Wang
| | - Tao Sun
- Ningxia Key Laboratory of Cerebrocranial Disease, The Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, China
- Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, China
- *Correspondence: Tao Sun
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RNA-sequence reveals differentially expressed genes affecting the crested trait of Wumeng crested chicken. Poult Sci 2021; 100:101357. [PMID: 34329989 PMCID: PMC8335650 DOI: 10.1016/j.psj.2021.101357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 06/22/2021] [Indexed: 12/12/2022] Open
Abstract
Wumeng crested chicken has a cluster of slender feathers on its head, and the underlying skull region exhibits an obvious tumor-like protrusion. This is the typical skull structure of crested chickens. The associated regulatory genes are located on autosomes and are incompletely dominant. This trait is related to brain herniation, but the genetic mechanisms of its formation and development are unclear. In this study, RNA sequencing (RNA-Seq) analysis was conducted on 6 skull tissue samples from 3 Wumeng crested chickens with prominent skull protrusions and 3 without a prominent skull protrusion phenotype. A total of 46,376,934 to 43,729,046 clean reads were obtained, the percentage of uniquely mapped reads compared with the reference genome was between 89.73%-91.00%, and 39,795,458-41,836,502 unique reads were obtained. Among different genomic regions, the highest frequency of sequencing reads occurred in exon regions (85.44-88.28%). Additionally, a total of 423 new transcripts and 26,999 alternative splicings (AS) events were discovered in this sequencing analysis. This study identified 1,089 differentially expressed genes (DEGs), among which 485 were upregulated and 604 were downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that the DEGs were enriched in terms related to signal transduction, cell development, cell differentiation, the lysosome, serine, and threonine metabolism, and the interaction of cytokines with cytokine receptors. Based on the comprehensive analysis of DEGs combined with reported quantitative trait loci (QTLs), the expression of BMP2, EPHA3, EPHB1, HOXC6, SCN2B, BMP7, and HOXC10 was verified by real-time quantitative polymerase chain reaction (qRT-PCR). The qRT-PCR results were consistent with the RNA-Seq results, indicating that these 7 genes may be candidates genes regulating the crested trait.
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Al-Ward H, Liu CY, Liu N, Shaher F, Al-Nusaif M, Mao J, Xu H. Voltage-Gated Sodium Channel β1 Gene: An Overview. Hum Hered 2021; 85:101-109. [PMID: 34038903 DOI: 10.1159/000516388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 04/01/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Voltage-gated sodium channels are protein complexes composed of 2 subunits, namely, pore-forming α- and regulatory β-subunits. A β-subunit consists of 5 proteins encoded by 4 genes (i.e., SCN1B-SCN4B). SUMMARY β1-Subunits regulate sodium ion channel functions, including gating properties, subcellular localization, and kinetics. Key Message: Sodium channel β1- and its variant β1B-subunits are encoded by SCN1B. These variants are associated with many human diseases, such as epilepsy, Brugada syndrome, Dravet syndrome, and cancers. On the basis of previous research, we aimed to provide an overview of the structure, expression, and involvement of SCN1B in physiological processes and focused on its role in diseases.
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Affiliation(s)
- Hisham Al-Ward
- Department of Biochemistry and Molecular Biology, Jiamusi University School of Basic Medical Sciences, Jiamusi, China
| | - Chun-Yang Liu
- Department of Biochemistry and Molecular Biology, Ankang University School of Medicine, Ankang, China
| | - Ning Liu
- Department of Biochemistry and Molecular Biology, Jiamusi University School of Basic Medical Sciences, Jiamusi, China
| | - Fahmi Shaher
- Department of Pathophysiology, Jiamusi University School of Basic Medical Sciences, Jiamusi, China
| | - Murad Al-Nusaif
- Department of Neurology, Dalian Medical University, Dalian, China
| | - Jing Mao
- Department of Biochemistry and Molecular Biology, Jiamusi University School of Basic Medical Sciences, Jiamusi, China
| | - Hui Xu
- Department of Biochemistry and Molecular Biology, Jiamusi University School of Basic Medical Sciences, Jiamusi, China
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Miziak B, Czuczwar S. Advances in the design and discovery of novel small molecule drugs for the treatment of Dravet Syndrome. Expert Opin Drug Discov 2020; 16:579-593. [PMID: 33275464 DOI: 10.1080/17460441.2021.1857722] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Introduction: Dravet syndrome (severe myoclonic epilepsy in infancy) begins in the first year of life characterized by generalized or unilateral clonic seizures that are frequently triggered by high fever. A subsequent worsening stage occurs (in years 1-4 of life) and seizure activity is accompanied by disturbed psychomotor development. The third stage of the disease, known as the 'stabilization phase,' is associated with seizures and intellectual impairment. Of note, a mutation in the voltage-gated sodium-channel gene α 1 subunit (SCN1A) has been found in around 85% of patients with Dravet syndrome.Areas covered: The authors review the current treatment strategies as well as potential drugs in the initial stages of clinical evaluation. The authors also review drugs with protective activity in mice models of Dravet syndrome.Expert opinion: Experimental data and results from initial clinical studies have brought attention to several drugs with various mechanisms of action including: ataluren (a suppressant of premature stop codons; under clinical evaluation), EPX-100, EPX-200, fenfluramine (serotonin modulators), soticlestat (an 24-hydroxylase cholesterol enzyme inhibitor), SPN-817 (an inhibitor of acetylcholinesterase), verapamil (a voltage-dependent calcium channel inhibitor) and STK-001 (an antisense oligonucleotide). The latter is scheduled for clinical evaluation.
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Affiliation(s)
- Barbara Miziak
- Department of Pathophysiology, Medical University of Lublin, Lublin, Poland
| | - Stanisław Czuczwar
- Department of Pathophysiology, Medical University of Lublin, Lublin, Poland
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