DEPDC5 mutations in familial and sporadic focal epilepsy.
OBJECTIVE
Mutations in the disheveled, Egl-10 and pleckstrin domain-containing protein 5 (DEPDC5) gene have emerged as an important cause of various familial focal epilepsy syndromes. However, the significance of DEPDC5 mutations in patients with sporadic focal epilepsy has yet to be characterized.


METHODS
We studied a kindred of familial focal epilepsy with variable foci using whole-exome sequencing. We subsequently studied a cohort of 293 patients with focal epilepsy and sequenced all exons of DEPDC5 using targeted resequencing.


RESULTS
We reported a Taiwanese family with a novel splice site mutation which affected mRNA splicing and activated the downstream mammalian target of rapamycin (mTOR) pathway. Among patients with focal epilepsies, the majority (220/293) of these patients had sporadic focal epilepsy without malformation of cortical development. Two (0.9%) of these patients had probably pathogenic mutations in the DEPDC5 gene.


CONCLUSIONS
Our finding suggests that DEPDC5 is not only the most common gene for familial focal epilepsy but also could be a significant gene for sporadic focal epilepsy. Since focal epilepsies account for more than 60% of all epilepsies, the effect of mTORC1 inhibitor on patients with focal epilepsy due to DEPDC5 mutations will be an important future direction of research.
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.|Department of Nursing, Meiho University, Pingtung, Taiwan.
M-H
http://orcid.org/0000-0002-4570-5712
MH
Tsai
Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
C-K
CK
Chan
Department of Pediatric Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Y-C
YC
Chang
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Y-T
YT
Yu
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
S-T
ST
Chuang
Whole Genome Research Core Laboratory of Human Diseases, Chang Gung Medical Foundation, Keelung, Taiwan.
W-L
WL
Fan
Genomics and Proteomics Core Laboratory, Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
S-C
SC
Li
Department of Pathology and Laboratory Medicine, Kaohsiung Veteran General Hospital, Kaohsiung, Taiwan.
T-Y
TY
Fu
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
W-N
WN
Chang
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
C-W
CW
Liou
Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Y-C
YC
Chuang
Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
C-C
CC
Ng
Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
D-Y
DY
Hwang
Division of Neurology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
K-S
KS
Lim
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004828:Epilepsies, Partial / Q000235:genetics* / Q000473:pathology; D005260:Female; D020690:GTPase-Activating Proteins; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D000076222:Mechanistic Target of Rapamycin Complex 1 / Q000235:genetics; D009154:Mutation; D010375:Pedigree; D012326:RNA Splicing / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics*; D058570:TOR Serine-Threonine Kinases / Q000235:genetics*; D000073359:Exome Sequencing
C000590398:DEPDC5 protein, human; D020690:GTPase-Activating Proteins; D012097:Repressor Proteins; D000076222:Mechanistic Target of Rapamycin Complex 1; D058570:TOR Serine-Threonine Kinases

DEPDC5
; familial; focal epilepsy; sporadic