探讨Dravet综合征中不同基因突变类型与临床表型的关系。

回顾性分析3例具有不同基因突变类型的Dravet综合征患儿的临床资料，分析典型及非典型Dravet综合征中临床表现和基因的遗传异质性，复习文献Dravet综合征不同基因突变类型及其相应的临床特征。

病例1，有典型的Dravet综合征临床表现，如热敏感性、智力运动发育落后、发作时间逐渐延长，出现癫痫持续状态，对多种抗癫痫药耐药等，存在新发的钠离子通道α1亚基因(SCN1A)突变，该突变高度预示其致病性。病例2，有Dravet综合征的一些不典型特征，如无热惊厥、发作时间短暂，轻度智力运动发育落后，仅表现出语言、社交的落后，存在罕见的γ-氨基丁酸受体亚基因(GABRA6)突变。病例3，有CHD2基因突变中典型的肌阵挛表现，但尚未表现出失神发作、全面性强直发作以及癫痫持续状态，具有以构音障碍为主要表现的运动落后。

除经典SCN1A以外其他不典型基因突变类型的Dravet综合征，其表型差异是非常普遍的，Dravet综合征定义应该为一个更广谱的系列。

To investigate the relationship between different types of gene mutations and clinical phenotypes in Dravet syndrome.

The clinical data of three patients with different types of gene mutations were analyzed retrospectively to illustrate the heterogeneity between gene mutation types and phenotypes in typical and atypical Dravet syndrome.Relevant literatures about the different types of gene mutations in Dravet syndrome and their corresponding clinical features were reviewed.

The first patient suffered from a very typical manifestation of Dravet syndrome, such as heat sensitivity, mental retardation, the onset time gradually extended, epileptic status, resistance to a variety of antiepileptic drugs, with a new sodium channel α1 gene (SCN1A) mutation which indicated its pathogenicity.The second patient was with some atypical characteristics of Dravet syndrome, such as no febrile seizure, short episodes of attack, mild mental development only showing the language or social retardation.He carried a rare γ-aminobutyric acid receptor subunit (GABRA6) mutation.The third patient had CHD2 gene mutation with the typical myoclonus performance, but didn′t manifest the absence of seizure generalized tonic-clonic seizure and status epilepticus, with dysphonia as the main performance of the movement retardation.

The phenotypic differences of Dravet syndrome in typical mutations other than SCN1A is very common , and the definition of Dravet syndrome should be more broad spectrum series.