Objective:To summarize the genotype and clinical phenotype characteristics of children with epilepsy associated with the SCN1B gene encoding the sodium channel β1 subunit. Methods:The genotypes and clinical phenotypes of patients with SCN1B variants among suspected genetic epilepsy cases treated at the Children′s Medical Center of Peking University First Hospital between May 2016 and July 2024 were analyzed. These variants were identified using next-generation sequencing and subsequently validated by Sanger sequencing or quantitative polymerase chain reaction methods. Results:A total of 17 patients were analyzed, including 8 males and 9 females. Ten cases of missense variations (including 2 with the same variations), 4 cases of deletion variations, and 1 case each of nonsense variations, splice site variations, and exons 4-5 deletions were identified. Among them, 6 cases had novel SCN1B variations. The variants in 11 cases were inherited from 1 parent. Eleven types of gene variants have not been reported yet. Onset of epilepsy ranged from 3 months to 5 years and 3 months old (median age: 14 months). Types of seizures included generalized tonic-clonic seizures (GTCS) in 14 cases, focal seizures in 9 cases, myoclonic seizures in 3 cases, atypical absence seizures in 2 cases and epilepsy spasms, tonic seizures and atonic seizures in 1 case each. Eleven cases had diverse seizure types. Fourteen cases (14/17) demonstrated fever sensitivity. Electroencephalography revealed focal discharges in 3 cases, coinciding with focal and generalized discharges in 3 additional cases, and multifocal discharges in 6 cases. Seizures were identified in 4 cases: 1 case of myoclonic seizures, 1 case of GTCS, 1 case of atypical absence seizures, and 1 case exhibiting both myoclonic and tonic seizures. Nine cases (9/17) were diagnosed with genetic epilepsy with febrile seizures plus, 1 case diagnosed with myoclonic epilepsy in infancy and 1 diagnosed with infant epileptic spasms syndrome. There were 2 cases of nonspecific developmental epileptic encephalopathy, while the remaining 4 cases could not be diagnosed with a specific epileptic syndrome. Effective antiseizure medications (ASMs) included valproate in 8 cases, levetiracetam in 5 cases, topiramate in 3 cases, clobazam in 2 cases, clonazepam and vigabatrin in 1 case each. Sodium channel blockers exacerbated seizures in 3 cases, specifically oxcarbazepine in 2 cases and lamotrigine in 1 case. At the last follow-up, seizures were controlled for at least 6 months in 14 patients (14/17), while seizures remained uncontrolled in 3 patients despite trialing 2 or more ASMs. Thirteen patients exhibited normal development, while 4 experienced developmental delays. Conclusions:The heterozygous variants in children with SCN1B gene-related epilepsy include missense, deletion, nonsense, splice site variants, and exon deletions. The correlation between different genetic variants and clinical phenotypes remains unclear. These variants are associated with epilepsy onset from infancy to early childhood, presenting with various seizure types, with GTCS being the most common. Phenotypic manifestations can vary significantly in severity, ranging from benign febrile seizures or febrile seizures plus to developmental epileptic encephalopathy. Valproic acid demonstrates the highest effectiveness rate, while the use of sodium channel blockers may worsen seizures in certain patients, necessitating cautious administration.

Objective:To summarize the clinical phenotype and genetic features of patients with relapsing encephalopathy with cerebellar ataxia (RECA) caused by ATP1A3 gene R756 variants. Methods:A retrospective analysis was performed on patients carrying the ATP1A3 gene R756 variants, identified by whole-exome sequencing of family members, at Capital Center for Children′s Health, Capital Medical University and Children's Medical Center, Peking University First Hospital from August 2005 to February 2024. Their clinical, laboratory, neuroimaging, electrophysiological and genetic characteristics were summarized. Results:A total of 13 RECA patients were enrolled in this study, including 8 males and 5 females. The age of onset was 8 months to 5 years, with a median age of onset of 18 months. All of 13 patients presented paroxysmal episodes of neurological decompensations triggered by fever and residual symptoms following the acute phase. During acute attack stage, ataxia was observed in all 13 cases, muscle weakness in 12 cases, dysarthria in 12 cases, altered consciousness in 10 cases, dysphagia in 10 cases, dystonic episodes in 4 cases, abnormal eye movement in 2 cases, choreoathetosis in 2 cases, and epileptic seizures in 1 case. All 13 patients had residual symptoms during the nonparoxysmal period, of whom 9 patients had ataxia, 9 patients had dysarthria, 4 patients had dystonia, 3 patients had cognitive disorders, and 1 patient had epileptic seizures. All 13 cases had ATP1A3 missense variants, and variant c.2266C>T/p.R756C was found in 6 cases, c.2267G>A/p.R756H in 5 cases, and c.2267G>T/p.R756L in 2 cases. Nine cases carried de novo variants, 4 with inherited variants. Conclusions:RECA caused by variants of ATP1A3 in residue 756 typically presents with an acute onset during infancy or early childhood, precipitated by febrile episodes and characterized by recurrent episodes of ataxia, with bulbar paralysis, muscle weakness and altered consciousness. Recurrence is common, and the most common persistent symptoms are cerebellar ataxia and dysarthria. A few patients have cognitive impairment. Three types of ATP1A3 gene variants R756C, R756H and R756L are related with RECA, and R756C is the most common variant.

Objective:To analyze the clinical features and diagnostic process of ring chromosome syndrome.Methods:Clinical data of 9 children with ring chromosome syndrome who were treated at the Children′s Medical Center of Peking University First Hospital from September 2009 to May 2025, were summarized and analyzed in a case series study. The data included clinical manifestations, types of epileptic seizures, genetic testing, treatment outcomes, and follow-up results, et al.Results:Among the 9 children with ring chromosome syndrome, there were 6 girls and 3 boys, including 4 children with ring chromosome 20 syndrome, 3 children with ring chromosome 14 syndrome, and 1 child each with ring chromosome 13 and 17 syndrome. All 9 children had de novo chromosomal variations. Among them, 3 children of ring chromosome 20 syndrome were mosaic, and the remaining 6 children were non-mosaic. All 9 children exhibited diverse clinical features, especially those with ring chromosome 20 syndrome, which presented with specific manifestations. The 4 children with ring chromosome 20 syndrome all had acute epileptic seizures as the initial symptom, with onset ages of 67, 39, 17, and 96 months, and all had focal seizures. One child with ring chromosome 20 syndrome had non-convulsive status epilepticus. Development of all 4 children with ring chromosome 20 syndrome was normal before seizure onset, but 3 children showed regression after onset. No physical deformities were observed in 4 children with ring chromosome 20 syndrome, and 2 children were misdiagnosed, 3 children underwent whole exome sequencing and copy number variation analysis in their families, with no abnormalities detected. All 4 children with ring chromosome 20 syndrome were diagnosed through chromosomal karyotype analysis, the intervals between onset and diagnosis were 2, 81, 19 and 13 months, respectively. Follow-up showed that epileptic seizures were not controlled in all 4 children with ring chromosome 20 syndrome. The other 5 children were characterized by developmental delay as the initial symptom, followed by epileptic seizures between 3 and 24 months of age. Developmental regression of the other 5 children did not occur after onset, 2 of them had microcephaly, and 3 had wide-set eyes. No misdiagnoses were reported in these 5 children, and the intervals between onset and diagnosis were 7, 3, 55, 3, and 106 months, respectively. Follow-up showed that epileptic seizures were controlled in these 5 children. Conclusions:Ring chromosome 20 syndrome typically manifest with epilepsy as the initial symptom and are refractory to drug treatment, their early development is entirely normal. Ring chromosome 13, 14, and 17 syndrome are characterized by developmental delay from an early age, followed by the onset of epileptic seizures, which are easily controlled. Conventional whole exome sequencing and copy number variation analysis in families rarely detect ring chromosome abnormalities. Early chromosomal karyotype analysis is essential for the diagnosis of ring chromosome syndrome.

Objective:To explore the genetic and clinical characteristics of epilepsy related with ATP6V1A gene heterozygous variants.Methods:A case series study was conducted. The clinical data of 10 children of epilepsy associated with ATP6V1A gene variants who were admitted to the Children′s Medical Center, Peking University First Hospital from January 2019 to December 2024 was collected. The characteristics of children′ gene variation, clinical phenotype, auxiliary examination results, treatment and prognosis were analyzed.Results:Among the 10 children, there were 4 boys and 6 girls. All 10 children with ATP6V1A gene variants were de novo heterozygous variants, including 1 case of mosaic variant. A total of 9 different variants were identified and 7 variants have not been reported previously. The age at epilepsy onset was 28 (9, 48) months. Five children experienced their first seizure as a fever induction. The types of epileptic seizures included focal seizures in 6 children, epileptic spasms in 5 children, tonic spasms and atonic seizures in 1 child respectively. Three children had 2 seizure types. Global developmental delays were exhibited in 8 children, 2 of whom manifested autism spectrum disorder phenotypes. Two children showed normal development. Electroencephalography revealed slowed background activity in 5 children. Interictal epileptiform discharges were recorded in 9 cases, including hypsarrhythmia, focal, multifocal or generalized discharges. Clinical seizures were captured in 4 children. Brain magnetic resonance imaging abnormalities were found in 4 children, including frontotemporal cortical dysplasia, prominent sulci, delayed myelination of white matter, dysplasia of the corpus callosum, bilateral ventricular enlargement, and cerebral atrophy. Five children were diagnosed with developmental and epileptic encephalopathy (DEE), and 4 of them were diagnosed with infantile epileptic spasms syndrome. At the last follow-up, the age was 78 (25, 120) months. Seizures were controlled in 6 children, while 4 children had uncontrolled seizures despite treatment with ≥3 anti-seizure medications. Conclusions:All children with ATP6V1A gene related epilepsy harbored de novo heterozygous missense variants, with few showing mosaic variants. Seizure onset age ranged widely from the neonatal period to childhood. The predominant seizure types were focal seizures and epileptic spasms. The phenotypic spectrum may exhibit DEE, while a minority maintain normal development.

Objective:To analyze the clinical features and diagnostic process of ring chromosome syndrome.Methods:Clinical data of 9 children with ring chromosome syndrome who were treated at the Children′s Medical Center of Peking University First Hospital from September 2009 to May 2025, were summarized and analyzed in a case series study. The data included clinical manifestations, types of epileptic seizures, genetic testing, treatment outcomes, and follow-up results, et al.Results:Among the 9 children with ring chromosome syndrome, there were 6 girls and 3 boys, including 4 children with ring chromosome 20 syndrome, 3 children with ring chromosome 14 syndrome, and 1 child each with ring chromosome 13 and 17 syndrome. All 9 children had de novo chromosomal variations. Among them, 3 children of ring chromosome 20 syndrome were mosaic, and the remaining 6 children were non-mosaic. All 9 children exhibited diverse clinical features, especially those with ring chromosome 20 syndrome, which presented with specific manifestations. The 4 children with ring chromosome 20 syndrome all had acute epileptic seizures as the initial symptom, with onset ages of 67, 39, 17, and 96 months, and all had focal seizures. One child with ring chromosome 20 syndrome had non-convulsive status epilepticus. Development of all 4 children with ring chromosome 20 syndrome was normal before seizure onset, but 3 children showed regression after onset. No physical deformities were observed in 4 children with ring chromosome 20 syndrome, and 2 children were misdiagnosed, 3 children underwent whole exome sequencing and copy number variation analysis in their families, with no abnormalities detected. All 4 children with ring chromosome 20 syndrome were diagnosed through chromosomal karyotype analysis, the intervals between onset and diagnosis were 2, 81, 19 and 13 months, respectively. Follow-up showed that epileptic seizures were not controlled in all 4 children with ring chromosome 20 syndrome. The other 5 children were characterized by developmental delay as the initial symptom, followed by epileptic seizures between 3 and 24 months of age. Developmental regression of the other 5 children did not occur after onset, 2 of them had microcephaly, and 3 had wide-set eyes. No misdiagnoses were reported in these 5 children, and the intervals between onset and diagnosis were 7, 3, 55, 3, and 106 months, respectively. Follow-up showed that epileptic seizures were controlled in these 5 children. Conclusions:Ring chromosome 20 syndrome typically manifest with epilepsy as the initial symptom and are refractory to drug treatment, their early development is entirely normal. Ring chromosome 13, 14, and 17 syndrome are characterized by developmental delay from an early age, followed by the onset of epileptic seizures, which are easily controlled. Conventional whole exome sequencing and copy number variation analysis in families rarely detect ring chromosome abnormalities. Early chromosomal karyotype analysis is essential for the diagnosis of ring chromosome syndrome.

Objective:To explore the genetic and clinical characteristics of epilepsy related with ATP6V1A gene heterozygous variants.Methods:A case series study was conducted. The clinical data of 10 children of epilepsy associated with ATP6V1A gene variants who were admitted to the Children′s Medical Center, Peking University First Hospital from January 2019 to December 2024 was collected. The characteristics of children′ gene variation, clinical phenotype, auxiliary examination results, treatment and prognosis were analyzed.Results:Among the 10 children, there were 4 boys and 6 girls. All 10 children with ATP6V1A gene variants were de novo heterozygous variants, including 1 case of mosaic variant. A total of 9 different variants were identified and 7 variants have not been reported previously. The age at epilepsy onset was 28 (9, 48) months. Five children experienced their first seizure as a fever induction. The types of epileptic seizures included focal seizures in 6 children, epileptic spasms in 5 children, tonic spasms and atonic seizures in 1 child respectively. Three children had 2 seizure types. Global developmental delays were exhibited in 8 children, 2 of whom manifested autism spectrum disorder phenotypes. Two children showed normal development. Electroencephalography revealed slowed background activity in 5 children. Interictal epileptiform discharges were recorded in 9 cases, including hypsarrhythmia, focal, multifocal or generalized discharges. Clinical seizures were captured in 4 children. Brain magnetic resonance imaging abnormalities were found in 4 children, including frontotemporal cortical dysplasia, prominent sulci, delayed myelination of white matter, dysplasia of the corpus callosum, bilateral ventricular enlargement, and cerebral atrophy. Five children were diagnosed with developmental and epileptic encephalopathy (DEE), and 4 of them were diagnosed with infantile epileptic spasms syndrome. At the last follow-up, the age was 78 (25, 120) months. Seizures were controlled in 6 children, while 4 children had uncontrolled seizures despite treatment with ≥3 anti-seizure medications. Conclusions:All children with ATP6V1A gene related epilepsy harbored de novo heterozygous missense variants, with few showing mosaic variants. Seizure onset age ranged widely from the neonatal period to childhood. The predominant seizure types were focal seizures and epileptic spasms. The phenotypic spectrum may exhibit DEE, while a minority maintain normal development.

Objective:To summarize the genotype and clinical phenotype characteristics of children with epilepsy associated with the SCN1B gene encoding the sodium channel β1 subunit. Methods:The genotypes and clinical phenotypes of patients with SCN1B variants among suspected genetic epilepsy cases treated at the Children′s Medical Center of Peking University First Hospital between May 2016 and July 2024 were analyzed. These variants were identified using next-generation sequencing and subsequently validated by Sanger sequencing or quantitative polymerase chain reaction methods. Results:A total of 17 patients were analyzed, including 8 males and 9 females. Ten cases of missense variations (including 2 with the same variations), 4 cases of deletion variations, and 1 case each of nonsense variations, splice site variations, and exons 4-5 deletions were identified. Among them, 6 cases had novel SCN1B variations. The variants in 11 cases were inherited from 1 parent. Eleven types of gene variants have not been reported yet. Onset of epilepsy ranged from 3 months to 5 years and 3 months old (median age: 14 months). Types of seizures included generalized tonic-clonic seizures (GTCS) in 14 cases, focal seizures in 9 cases, myoclonic seizures in 3 cases, atypical absence seizures in 2 cases and epilepsy spasms, tonic seizures and atonic seizures in 1 case each. Eleven cases had diverse seizure types. Fourteen cases (14/17) demonstrated fever sensitivity. Electroencephalography revealed focal discharges in 3 cases, coinciding with focal and generalized discharges in 3 additional cases, and multifocal discharges in 6 cases. Seizures were identified in 4 cases: 1 case of myoclonic seizures, 1 case of GTCS, 1 case of atypical absence seizures, and 1 case exhibiting both myoclonic and tonic seizures. Nine cases (9/17) were diagnosed with genetic epilepsy with febrile seizures plus, 1 case diagnosed with myoclonic epilepsy in infancy and 1 diagnosed with infant epileptic spasms syndrome. There were 2 cases of nonspecific developmental epileptic encephalopathy, while the remaining 4 cases could not be diagnosed with a specific epileptic syndrome. Effective antiseizure medications (ASMs) included valproate in 8 cases, levetiracetam in 5 cases, topiramate in 3 cases, clobazam in 2 cases, clonazepam and vigabatrin in 1 case each. Sodium channel blockers exacerbated seizures in 3 cases, specifically oxcarbazepine in 2 cases and lamotrigine in 1 case. At the last follow-up, seizures were controlled for at least 6 months in 14 patients (14/17), while seizures remained uncontrolled in 3 patients despite trialing 2 or more ASMs. Thirteen patients exhibited normal development, while 4 experienced developmental delays. Conclusions:The heterozygous variants in children with SCN1B gene-related epilepsy include missense, deletion, nonsense, splice site variants, and exon deletions. The correlation between different genetic variants and clinical phenotypes remains unclear. These variants are associated with epilepsy onset from infancy to early childhood, presenting with various seizure types, with GTCS being the most common. Phenotypic manifestations can vary significantly in severity, ranging from benign febrile seizures or febrile seizures plus to developmental epileptic encephalopathy. Valproic acid demonstrates the highest effectiveness rate, while the use of sodium channel blockers may worsen seizures in certain patients, necessitating cautious administration.

Objective:To summarize the clinical phenotype and genetic features of patients with relapsing encephalopathy with cerebellar ataxia (RECA) caused by ATP1A3 gene R756 variants. Methods:A retrospective analysis was performed on patients carrying the ATP1A3 gene R756 variants, identified by whole-exome sequencing of family members, at Capital Center for Children′s Health, Capital Medical University and Children's Medical Center, Peking University First Hospital from August 2005 to February 2024. Their clinical, laboratory, neuroimaging, electrophysiological and genetic characteristics were summarized. Results:A total of 13 RECA patients were enrolled in this study, including 8 males and 5 females. The age of onset was 8 months to 5 years, with a median age of onset of 18 months. All of 13 patients presented paroxysmal episodes of neurological decompensations triggered by fever and residual symptoms following the acute phase. During acute attack stage, ataxia was observed in all 13 cases, muscle weakness in 12 cases, dysarthria in 12 cases, altered consciousness in 10 cases, dysphagia in 10 cases, dystonic episodes in 4 cases, abnormal eye movement in 2 cases, choreoathetosis in 2 cases, and epileptic seizures in 1 case. All 13 patients had residual symptoms during the nonparoxysmal period, of whom 9 patients had ataxia, 9 patients had dysarthria, 4 patients had dystonia, 3 patients had cognitive disorders, and 1 patient had epileptic seizures. All 13 cases had ATP1A3 missense variants, and variant c.2266C>T/p.R756C was found in 6 cases, c.2267G>A/p.R756H in 5 cases, and c.2267G>T/p.R756L in 2 cases. Nine cases carried de novo variants, 4 with inherited variants. Conclusions:RECA caused by variants of ATP1A3 in residue 756 typically presents with an acute onset during infancy or early childhood, precipitated by febrile episodes and characterized by recurrent episodes of ataxia, with bulbar paralysis, muscle weakness and altered consciousness. Recurrence is common, and the most common persistent symptoms are cerebellar ataxia and dysarthria. A few patients have cognitive impairment. Three types of ATP1A3 gene variants R756C, R756H and R756L are related with RECA, and R756C is the most common variant.

Objective:To explore the distribution of the copy number of survival motor neuron gene 2 ( SMN2) and the transcript level of the full-length SMN2 ( fl-SMN2) transcript level in patients with type 1-3 spinal muscular atrophy (SMA), and to evaluate their influences on disease severity, progression, and prognosis. Methods:It was a retrospective study involving 78 therapy-naive SMA patients with SMN1 gene homozygous deletion who were diagnosed and treated in the Capital Institute of Pediatrics from January 2019 to December 2021.Cross-sectional clinical data, including age at onset, motor milestones, and complications were recorded.They were followed up for monitoring motor function degeneration and survival.The copy number of SMN2 and the transcript level of fl-SMN2 were detected.Differences between groups were compared by the Student′s t-test or One- Way ANOVA or Chi- square test.Kaplan-Meier analysis was used for survival analysis, and Kendall′ s tau- c was performed to assess the correlation of these two biomarkers with SMA phenotypes, age at onset, motor milestones, and survival. Results:Of the 78 SMA patients, there were 17 cases (21.8%) of type 1, 34 cases(43.6%) of type 2, and 27 cases(34.6%) of type 3.Seven cases(41.2%) type 1 SMA patients died, with a median survival time of 11 months, and no deaths were observed in type 2 and type 3 SMA patients.There was a significant difference in the median age at onset among SMA patients with 2, 3, and 4 copies of SMN2 (1.8, 12.0, and 24.0 months, respectively; F=4.943, P=0.01). The mean transcript level of fl-SMN2 in type 1, 2 and 3 SMA patients were 196.25±68.79, 331.21±108.79 and 455.69±122.27, respectively ( F=37.154, P<0.001). The survival rate of SMA with 2 SMN2 copies at 1, 2, and 5 years were 50.5%, 0, and 0, respectively, and their median survival age was 7 months.The survival rate of SMA with 3 and 4 SMN2 copies at 5 years were 97.4% and 100.0%, respectively.Moreover, a negative correlation was observed between the transcript level of fl-SMN2 and phenotype severity ( Kendall′ s tau- c=-0.444, P<0.001), and the transcript level of fl-SMN2 of the survival group was much higher than that of the death group (342.93±125.74 vs.212.14±92.31). More copies of SMN2 and higher transcript level of fl- SMN2 indicated more motor function acquisitions (head control, sitting and walking) ( P<0.001). In addition, there was a significant difference in the transcription level of fl-SMN2 between the undegenerated group and the degenerated group in sitting and standing ( F=5.432, P=0.023 and F=4.315, P=0.047, respectively). Conclusions:Both the copy number of SMN2 and the transcript level of fl-SMN2 are correlated with SMA severity, survival, and motor milestones, serving as valuable biomarkers for evaluating phenotypic severity of SMA.The transcript level of fl-SMN2 s may play an important role in the degeneration of sitting and standing.