Winawer M R, Rabinowitz D, Pedley T A, Hauser W A, Ottman R
G.H. Sergievsky Center, Department of Neurology, Columbia University, New York, NY 10032, USA.
Neurology. 2003 Dec 9;61(11):1576-81. doi: 10.1212/wnl.61.11.1576.
To examine the relationship between genotype and phenotype in idiopathic generalized epilepsies (IGEs) using a novel approach that focuses on seizure type rather than syndrome.
The authors evaluated whether the genetic effects on myoclonic seizures differ from the genetic effects on absence seizures. For this purpose, they studied 34 families containing 2 or more members with IGEs and assessed whether the number of families concordant for seizure type exceeded that expected by chance. The authors performed a similar analysis to examine the genetic contributions to juvenile myoclonic epilepsy (JME), juvenile absence epilepsy (JAE), and childhood absence epilepsy (CAE).
The observed number of families concordant for seizure type (myoclonic, absence, or both) was greater than expected (20 vs 7.51; p < 0.0001). The observed number of families concordant for syndrome was greater than expected when JME was compared with absence epilepsies (JAE+CAE) (17 vs 11.9; p < 0.012) but not when JAE was compared with CAE (8 vs 6.82; p = 0.516).
These results provide evidence for distinct genetic effects on absence and myoclonic seizures, suggesting that examining the two seizure types separately would be useful in linkage studies of idiopathic generalized epilepsies. The approach presented here can also be used to discover other clinical features that could direct division of epilepsies into groups likely to share susceptibility genes.
采用一种聚焦于发作类型而非综合征的新方法，研究特发性全身性癫痫（IGE）的基因型与表型之间的关系。
作者评估了对肌阵挛发作的遗传效应是否不同于对失神发作的遗传效应。为此，他们研究了34个家庭，每个家庭中有2名或更多患有IGE的成员，并评估了发作类型一致的家庭数量是否超过偶然预期。作者进行了类似分析，以研究对青少年肌阵挛癫痫（JME）、青少年失神癫痫（JAE）和儿童失神癫痫（CAE）的遗传贡献。
发作类型（肌阵挛、失神或两者皆有）一致的家庭观察数量大于预期（20对7.51；p<0.0001）。当将JME与失神癫痫（JAE+CAE）进行比较时，综合征一致的家庭观察数量大于预期（17对11.9；p<0.012），但当将JAE与CAE进行比较时则不然（8对6.82；p=0.516）。
这些结果为失神发作和肌阵挛发作存在不同遗传效应提供了证据，表明在特发性全身性癫痫的连锁研究中分别研究这两种发作类型将是有用的。这里介绍的方法还可用于发现其他临床特征，这些特征可指导将癫痫分为可能共享易感基因的组。
