Mutations in the voltage gated potassium channel gene KCNQ2 and the homologous 
gene KCNQ3 have been found to cause a rare monogenic subtype of idiopathic 
generalized epilepsy, the benign familial neonatal convulsions. Recently, the 
heteromeric KCNQ2/KCNQ3 channel was found to contribute to the native M-current, 
one of the most important regulators of neuronal excitability. By performing a 
systematic mutation scan of the coding region and an association study involving 
a frequent Thr752Asn substitution polymorphism, we, therefore, investigated 
whether allelic variation of the KCNQ2 gene confers susceptibility to common 
subtypes of idiopathic generalized epilepsy. Our results do not provide evidence 
that allelic variation of the KCNQ2 gene contributes a common and relevant 
effect to the pathogenesis of common subtypes of idiopathic generalized 
epilepsy.