Phenotype and genotype of epilepsy patients related to CLCN4 variants
10.3760/cma.j.cn113694-20240321-00177
- VernacularTitle:CLCN4基因变异相关癫痫的临床表型及基因变异特点
- Author:
Wenrong ZHANG
1
;
Ying YANG
;
Miaomiao CHENG
;
Ting WANG
;
Changhao LIU
;
Xiaoling YANG
;
Yuehua ZHANG
Author Information
1. 北京大学第一医院儿科，北京 100034
- Keywords:
CLCN4 gene;
Epilepsy;
Developmental delay;
Prognosis
- From:
Chinese Journal of Neurology
2024;57(9):968-974
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To summarize the clinical phenotypes and genetic variations of children with epilepsy related to CLCN4 gene mutations. Methods:A retrospective analysis was conducted on 9 children with epilepsy who were diagnosed with CLCN4 gene mutations through whole-exome sequencing of family members. These children were treated at the Department of Pediatrics, Peking University First Hospital from December 2016 to March 2024. Their clinical manifestations, electroencephalogram, cranial imaging characteristics, and treatment follow-up were reviewed. Results:Among the 9 children, 6 were male and 3 were female. All cases involved de novo mutations. Three cases carried the c.823G>A/p.V275M variant, 2 cases carried the c.2152C>T/ p.R718W variant, 1 case carried the c.1630G>A/pG544R variant, and 1 case carried the c.2167C>T/ p.R723W variant. Two cases carried the unreported new variant c.848G>T/p.S283I and c.818G>A/ p.G273E. The onset age of epilepsy ranged from 55 days to 10 years, with a median onset age of 14 months. Seven out of 9 children had epilepsy onset before the age of 2 years. The types of seizures varied: 8 had focal seizures, 1 had generalized tonic-clonic seizures, 2 had myoclonic seizures, 1 had epileptic spasms, and 1 had atypical absence seizures. Three children experienced multiple types of seizures. All 9 children exhibited developmental delays to varying degrees: 8 had global developmental delay and 1 had cognitive developmental delay. Developmental delays were observed in 7 children before the onset of epilepsy. Clinically, 1 child was diagnosed with infantile epileptic spasms syndrome, 7 with unclassified developmental and epileptic encephalopathy, and 1 with focal epilepsy with developmental delay. At the last follow-up, the age of the children ranged from 2 years and 5 months to 13 years and 9 months. Seizures had been controlled in 3 children for a duration of 4 to 12 months. Conclusions:De novo variants are common in CLCN4 variants. Most seizures onset in infancy, seizure types are various, and focal seizures are common. Most of them have developmental delay and drug-resistant epilepsy, and some of them have developmental delay before seizure onset, which is consistent with the characteristics of developmental and epileptic encephalopathy.
