Mutations in the three genes SCN1A, SCN1B and GABRG2, all encoding subunits of ion channels, have been known to cause generalized epilepsy with febrile seizures plus (GEFS+) in families of different origin.
To study the occurrence of mutations in these genes in families with GEFS+ or a GEFS+ resembling phenotype of Scandinavian origin.
We performed linkage analysis in 19 Scandinavian families with a history of febrile seizures (FS) and epilepsy or GEFS+. Where linkage could not be excluded, the genes of interest were sequenced.
We identified only one mutation in SCN1A, which seems to be a rare variant with no functional consequence.
This suggests that mutations in these three genes are not a prevalent cause of familial cases of FS and epilepsy or GEFS+ in Scandinavia.