SCN1A基因编码I 型电压依赖型钠通道(Nav1.1)，Nav1.1临床上与癫痫关系密切，且是多种抗癫痫药物(AEDs)作用的靶点。已知癫痫有关的SCN1A突变可发生在非编码蛋白的内含子，以与基因剪切关系密切的固有剪切位点突变多见，多与严重表型相关。我们此前在癫痫患者中筛查到7个SCN1A内含子突变，除固有剪切位点外，还发现可变剪切位点，甚至深部内含子突变。这些突变的表型轻重不一，AEDs反应差异明显，存在AEDs加重发作。因内含子功能复杂，基因剪切机制未明，其潜在机制不清。因此，我们进行对照设计，通过质粒异源细胞体外表达，研究不同内含子突变对基因剪切、Nav1.1蛋白表达、亚分子定位和钠通道电生理的影响；给予不同类型和浓度AEDs处理，观察通道蛋白表达和电生理改变；综合数据，探讨其与临床的可能关系。结果将对揭示SCN1A内含子突变的致痫机制，对钠通道功能和AEDs疗效的影响有重要意义。

SCN1A gene encode voltage-gated sodium channel type I (Nav1.1), which plays a critical role in brain functional activity and served as a target of some anti-epileptic drugs (AEDs). SCN1A is now the most relevant epilepsy gene. Epilepsy related SCN1A mutations can occur in intron with non-protein coding. Most of them were mutations in canonical splice junction, i.e. splice site mutation, which closely related with gene splicing and predominantly associated with severe phenotypes. However, we previously detected seven SCN1A intronic mutations in patients with epilepsy, in which not only splice site mutation, but also mutations located in variant splice motifs as well as in deep intronic area were indentified. It’s noted that the severity of phenotypes in these patients were various, and AEDs responses were obvious difference in them, even seizure aggravation by AEDs. The underlined mechanism is unknown and warrants further studies, due to the functional complexity of intron and unclear process in gene spicing. It is suspected whether mutations on the different site of SCN1A intron may result in different consequences of SCN1A splicing and severe or mild functional changes of Nav1.1 and are associated phenotype severity and AEDs response. In present study, recombinant expression vector and mutant plasmids will be constructed. The functional alterations of these mutants will be examined by using expressions of heterogonous cells in vitro, including detection of the consequent of SCN1A gene splicing through Minigene splicing assay and Nav1.1 protein expressed in cell membrane, as well as examination of electrophysiological properties of sodium channel by the whole cell patch clamp technique. Subsequently, different types of AEDs with different dosage will be administrated to each mutant to observe their electrophysiological properties changes of sodium channel. Comprehensive results of in vitro experiments will be analyzed to explore the relationship among genotypes, phenotypes, functional types as well as AEDs responses. This study will help understand the mechanism of epilepsy caused by SCN1A intronic mutation and disclose the effects of functional changes on the sodium channel function and AEDs reaction.