Long-term course of early onset developmental and epileptic encephalopathy associated with 2q24.3 microduplication

Epilepsy & Behavior Reports

Naomi Tsuchida¹  Satoko Miyatake²  Kou Nishimura²  Takanori Yamagata²  Toshiki Takenouchi³  Takuya Masuda⁴  Hitoshi Osaka⁴  Takao Takahashi⁵  Naomichi Matsumoto⁵ 

[1] Corresponding author at: Division of Pediatrics, Jichi Medical University, 2411-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.;Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan;Department of Pediatric Neurology, Ise Keiyu Hospital, 2-7-28 Tokiwa, Ise, Mie 516-0041, Japan;Department of Pediatrics, Jichi Medical University, 2411-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan;Department of Pediatrics, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;

关键词: 2q24.3 microduplication;    Developmental and epileptic encephalopathy;    Voltage-gated sodium channel;    Copy number variations;   

DOI  :  

来源: DOAJ

【 摘 要 】

Copy number variations (CNVs) have been related to developmental and epileptic encephalopathy (DEE). The 2q24.3 region includes a cluster of genes for voltage-gated sodium channels (SCN) and CNVs in this region cause DEE. However, the long-term course of DEE with a 2q24.3 duplication has not been described. A 20-year-old female developed epileptic encephalopathy in early infancy that was resistant to various antiseizure medications. Her seizures disappeared after starting vitamin B6 therapy. Therefore, her epilepsy was considered pyridoxine-dependent epilepsy. At 16 years old, whole exome sequencing revealed a 2q24.3 microduplication including SCN1A, SCN2A, SCN3A, SCN7A, and SCN9A. Quantitative PCR detected an increased copy number of 1.3 Mb on 2q24.3 involving these genes, but no gene mutation accounting for pyridoxine-dependent epilepsy. Considering that with this duplication she was reported to be seizure-free after infancy, she was able to be off antiseizure medications including vitamin B6. Our case involvingdrug-resistant epilepsy in early infancy had no recurrent seizures during long-term follow up. Detecting CNVs using whole exome sequencing data was useful to identify a 2q24.3 duplication unassociated with pyridoxine-dependent epilepsy, leading to cessation of unnecessary medications.

【 授权许可】

Unknown