ABSTRACT
A mutational approach has proven to be invaluable to investigators examining the roles of gene products in complex biological processes within prokaryotic and cultured eukaryotic cells. Two major developments have made gene targeting experiments feasible: the generation of embryonic stem cells, and the elucidation of techniques to achieve gene targeting in mammalian cells. The advent of gene targeting technology has produced a dramatic increase in the number of mutant epilepsy models. A targeting construct is generated which typically consists of a long target gene sequence into which a loss-of-function mutation has been engineered. The advent of gene targeting technology has produced a dramatic increase in the number of mutant epilepsy models. A number of important considerations in the interpretation of mutant phenotypes are illustrated by the analysis of an epilepsy syndrome in serotonin 5-HT2C receptor null mutant mice. The new murine models of epilepsy are revealing that a wide variety of genes may determine the heritability of seizure predisposition.
