Clinical genetic analysis of a epileptic family with DEPDC5 gene variant and a patient with a de novo variant in the GABRA1 gene
10.3760/cma.j.cn113694-20240416-00245
- VernacularTitle:DEPDC5基因变异的癫痫大家系及其中1例携带 GABRA1基因新发变异患者的临床遗传学分析
- Author:
Yaya YANG
1
;
Yidan WANG
;
Jian GAO
Author Information
1. 河北省人民医院生殖遗传科，石家庄050051
- Keywords:
Epilepsy;
Mutation;
Pedigree;
Genetic counseling
- From:
Chinese Journal of Neurology
2024;57(10):1127-1135
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To report a large family of epileptic seizures caused by DEPDC5 gene variation, and to conduct a clinical genetic analysis on a proband in this family with both DEPDC5 gene mutation and a de novo GABRA1 gene mutation. Methods:The medical records of a family suffering from epilepsy due to a newly identified DEPDC5 gene variant were compiled from cases admitted to Hebei General Hospital in January 2024. The relevant genetic detection was carried out by sampling the peripheral blood of the family members. The whole exome sequencing techniques were employed for the identification of pathogenic mutation sites in the proband. The next generation sequencing technology was utilized for other family members to identify disease-causing mutation sites associated with the clinical phenotype of patients, and these findings were confirmed using first-generation Sanger sequencing technology. Results:The proband, who experienced seizures in early childhood and harbored two gene mutation sites, exhibited an early onset age along with significant delays in both intellectual and motor development. The primary clinical manifestations included focal seizures, myoclonus, and tonic-clonic symptoms. When compared with other family members who had the onset of epilepsy during adolescence, carried only one mutation site, and had generalized epileptic seizures and mostly accompanied by attention deficit hyperactivity disorder, the proband showed obvious clinical heterogeneity. The results of whole exome sequencing indicated that the proband had both GABRA1 c.640C>T(p.Arg214Cys) and DEPDC5 c.4348A>T(p.Lys1450 *) mutations inherited from the father. The mutation inherited from the father was reported here for the first time and had not been reported before, with the paternal mutation traceable to the proband's grandfather, while the proband's mother and grandmother were found to be devoid of the mutation. In this family, 5 patients with similar seizure phenotype all had pathogenic mutations at the same locus of the DEPDC5 gene(c.4348A>T, p.Lys1450 *), and the remaining 3 patients with seizure symptoms were not tested. Conclusions:The DEPDC5 gene mutation is the cause of the disease in this family, and the c.4348A>T is the newly discovered mutation site. The proband carries the mutation sites of both GABRA1 gene and DEPDC5 gene. The clinical manifestations of proband are significantly heterogeneous compared with those of his family members.
