A family study of cataplexy and epilepsy due to mutations in the KCNA1 gene and literature review
10.3760/cma.j.issn.1673-4912.2025.07.009
- VernacularTitle:KCNA1基因突变致猝倒及癫痫一家系分析并文献复习
- Author:
Li LIN
1
;
Xiaoling ZHAO
;
Danqun JIN
;
Nannan LI
;
Bin YANG
Author Information
1. 安徽省儿童医院儿童神经科，合肥 230051
- Publication Type:Journal Article
- Keywords:
KCNA1 gene;
Cataplexy;
Epilepsy;
Sodium channel blocker
- From:
Chinese Pediatric Emergency Medicine
2025;32(7):524-529
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical and genetic characteristics of a family with cataplexy and epilepsy caused by KCNA1 gene mutations. Methods:The clinical data of a family with KCNA1 gene mutations leading to cataplexy and epilepsy who hospitalized in the Department of Pediatric Neurology at Anhui Children's Hospital in August 2022 were collected，and their clinical manifestations，imaging，electroencephalogram，gene testing results and treatment were analyzed. A total of 68 pathogenic or potentially pathogenic variants of the KCNA1 gene were identified by searching the database of CNKI，Wanfang Data Knowledge Service Platform, ClinVar, dbSNP and PubMed using the keyword‘KCNA1’between the establishment and August 2023. Results:The proband was a 9 years and 8 months old boy who initially presented with cataplexy induced by strenuous exercise or fatigue，followed by focal epilepsy. The whole exome sequencing detected heterozygous variation of exon 2 c.1006G>A（p.Gly336Arg）of KCNA1 gene，which was a missense mutation and was not reported in the country or abroad. Both the mother and brother of the proband detected heterozygous mutations at the same locus，and both had cataplexy induced by strenuous exercise or fatigue，but the type of seizure was generalized tonic-clonic seizure. The proband's grandmother，aunt，and brother all had seizures or cataplexy. Affected patients receiving different or the same anti-seizure drugs（sodium valproate，lamotrigine，phenytion sodium and carbamazepine）had varying degrees of relief，and those treated with sodium channel blockers had varying degrees of relief. A total of 68 mutation sites of KCNA1 gene were retrieved from domestic and foreign literature，mainly missense mutations，and most patients showed episodic ataxia type 1（EA1），and there was genetic heterogeneity between the genotype and phenotype of the variable patients. Conclusion:We have reported a heterozygous mutation in the KCNA1 gene c.1006G>A（p.Gly336Arg），which is a missense mutation and is easy to misdiagnose in patients with cataplexy and epilepsy as the main phenotypes. Patients with the KCNA1 mutation have different degrees of efficacy on sodium channel blockers.
