Related Experiment Video
Updated: Jun 29, 2025
A Behavioral Screen for Heat-Induced Seizures in Mouse Models of Epilepsy
Published on: July 12, 2021
[Correlation between clinical phenotypes and genotypes among 46 children with SCN1A-related developmental epileptic
Bingwei Peng1, Haixia Zhu, Yang Tian
1Department of Neurology, Women and Children's Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong 510120, China. gzchcwx@126.com.
Insights
This study found that SCN1A gene variants in children with developmental epileptic encephalopathy (DEE) show diverse clinical phenotypes. Truncating and missense variants have different onset ages, and missense variants outside the pore region are linked to myoclonic seizures.
Area of Science:
- Genetics
- Neurology
- Pediatrics
Context:
- Developmental Epileptic Encephalopathy (DEE) is a severe neurological disorder.
- SCN1A gene mutations are a common cause of DEE.
- Understanding genotype-phenotype correlations is crucial for diagnosis and treatment.
Purpose:
- To investigate the relationship between SCN1A gene variations and clinical presentations in children with DEE.
- To analyze correlations between specific SCN1A genotypes and phenotypes, including seizure types and neurodevelopmental outcomes.
Summary:
- 46 children with SCN1A-related DEE were analyzed.
- Two main phenotypes were observed: Epilepsy of Infancy with Migrating Focal Seizures (EIMFS) and Dravet Syndrome (DS).
- Truncating SCN1A variants were associated with earlier onset compared to missense variants. Missense variants outside the pore region correlated with myoclonic seizures.
Impact:
- This research clarifies genotype-phenotype correlations in SCN1A-related DEE.
- Findings can aid in predicting disease course and guiding therapeutic strategies.
- Highlights the importance of genetic testing for precise diagnosis and personalized management.
Objective:
To explore the correlation between clinical phenotypes and genotypes among 46 children with SCN1A-related developmental epileptic encephalopathy (DEE).
Methods:
Clinical data of 46 children with DEE and SCN1A variants identified at the Guangzhou Women and Children's Medical Center between January 2018 and June 2022 were collected. The children were grouped based on their age of onset, clinical manifestations, neurodevelopmental status, and results of genetic testing. The correlation between SCN1A genotypes and clinical phenotypes was analyzed.
Results:
Among the 46 patients, 2 children (4.35%) had developed the symptoms before 3 months of age, 42 (91.30%) were between 3 to 9 months, and 2 cases (4.35%) were after 10 months. Two cases (4.35%) presented with epilepsy of infancy with migrating focal seizures (EIMFS), while 44 (95.7%) had presented with Dravet syndrome (DS), including 28 cases (63.6%) with focal onset (DS-F), 13 cases (29.5%) with myoclonic type (DS-M), 1 case (2.27%) with generalized type (DS-G), and 2 cases (4.55%) with status epilepticus type (DS-SE). Both of the two EIMFS children had severe developmental delay, and among the DS patients, 7 cases had normal development, while the remaining had developmental delay. A total of 44 variants were identified through genetic sequencing, which included 16 missense variants and 28 truncating variants. All EIMFS children had carried the c.677C>T (p.Thr226Met) missense variant. In the DS group, there was a significant difference in the age of onset between the missense variants group and the truncating variants group (P < 0.05). Missense variants were more common in D1 (7/15, 46.7%) and pore regions (8/15, 53.3%), while truncating variants were more common in D1 (12/28, 42.9%). Children with variants outside the pore region were more likely to develop myoclonic seizures.
Conclusion:
The clinical phenotypes of DEE are diverse. There is a difference in the age of onset between individuals with truncating and missense variants in the SCN1A gene. Missense variants outside the pore region are associated with a higher incidence of myoclonic seizures.
More Related Videos
08:22A Novel Strategy Combining Array-CGH, Whole-exome Sequencing and In Utero Electroporation in Rodents to Identify Causative Genes for Brain Malformations
Published on: December 1, 2017
09:57Author Spotlight: Advancing Pediatric Epilepsy Surgery in Children Through Novel Biomarkers and Enhanced Localization
Published on: September 20, 2024
Related Concept Videos
01:35Pedigree Analysis
01:24Arteries of the Lower Limbs
Various factors can trigger epilepsy, including genetic factors, brain damage, metabolic causes, and unknown etiology. Diagnosis of epilepsy involves electroencephalography (EEG), which...
01:13Seizures: Classification
Seizures are typically classified into two main categories: focal and generalized seizures.
Focal Seizures
Focal seizures originate from specific regions of the brain. These seizures are further sub-classified into two types: