Analysis of clinical phenotypes and genotypes in 13 patients with KCNQ2-associated epilepsy
10.3760/cma.j.cn113694-20210104-00006
- VernacularTitle:KCNQ2基因突变相关癫痫患者13例临床表型和基因型分析
- Author:
Pingping ZHANG
;
Xinna JI
;
Zhijie GAO
;
Yingying MAO
;
Qian CHEN
- From:
Chinese Journal of Neurology
2021;54(6):553-559
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To report the clinical features of KCNQ2-associated epilepsy and the novel mutations and unreported clinical phenotype of KCNQ2 gene, so as to provide help for treatment selection and prognosis evaluation.Methods:Among 979 patients with epilepsy and developmental delay who were admitted to the Department of Neurology,Children′s Hospital Affiliated to Capital Institute of Pediatrics from July 2015 to October 2019, a total of 13 patients were selected from 12 families with KCNQ2 gene mutation by whole exome sequencing technology. Suspected mutations were verified by Sanger sequencing on the probands and their parents to identify the source. The clinical phenotype and genotype were analyzed according to these results.Results:Among the 13 patients with epilepsy, the onset age of four cases were older than six months [two cases in infancy (epilepsy encephalopathy), one case in early childhood (epilepsy encephalopathy) and one case in adolescence (benign epilepsy)]. Eight cases were treated with oxcarbazepine, of whom five cases were seizure free, and two cases showed partial response (>50%). Two cases treated with topiramate were seizure free. Five novel mutations were found in this research, including c.379T>G(p.Y127D), c.1A>C(initial codon mutation), c.708G>C(p.W236C), c.1027G>T(p.A343S) and c.1649T>G(p.V550G).Conclusions:Although it was rare in clinical work, the variation of KCNQ2 gene existed in patients with childhood-onset epilepsy and adolescent-onset epilepsy. Meanwhile, five novel mutations of KCNQ2 gene were reported, which further expanded its gene spectrum. This research supported that oxcarbazepine was the efficient medicine for the KCNQ2-associated epilepsy. Genetic testing showed great help to the treatment of epilepsy.
