INTRODUCTION KCNT2 was recently recognized as a gene associated with neurodevelopmental disorder and epilepsy. CASE REPORT We present an additional observation of a 16-year-old male patient with a novel de novo KCNT2 likely pathogenic variant and review the five previously reported cases of de novo variants in this gene. DISCUSSION Whole exome sequencing identified the missense variant c.725C > A p.(Thr242Asn), which was confirmed by Sanger sequencing. Our patient has a refractory stereotyped and monomorphic type of hyperkinetic focal motor seizure, similar to what is seen in frontal lobe epilepsy, occurring only during sleep. This type of seizure is not usually seen in epileptic encephalopathies.

中文翻译：

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对 KCNT2 新发致病性变异导致具有额叶癫痫临床特征的癫痫性脑病的额外观察

简介 KCNT2 最近被认为是与神经发育障碍和癫痫相关的基因。病例报告 我们对一名 16 岁男性患者进行了额外的观察，该患者具有新的 KCNT2 可能致病性变异，并回顾了先前报道的五例该基因中的从头变异病例。讨论 全外显子组测序鉴定了错义变异 c.725C > A p.(Thr242Asn)，这通过 Sanger 测序得到证实。我们的患者患有难治性刻板和单形型多动性局灶性运动发作，类似于额叶癫痫，仅在睡眠期间发生。这种类型的癫痫发作通常不会出现在癫痫性脑病中。