Sept. 18 (HealthDay News) -- Mutations in a sodium channel gene are associated with fever-induced seizures and a severe form of epilepsy called Dravet syndrome in children 6 months and younger, a new study has found.

American and Dutch researchers studied a large family with a history of febrile seizures and zeroed in on mutations in the SCN9A sodium channel gene. When the mutation was introduced into mice, the rodents had significantly lower thresholds for seizures than those without the mutation. The researchers then confirmed their findings by expanding the study to include people who were not related.

SCN9A is the fifth gene determined to be linked to fever-induced, or febrile, seizures. Previously, the gene had not been suspected to play a role in seizures or epilepsy.

"This gene gives us a much-needed novel target for developing more effective drugs to treat those children with debilitating seizures," the study's first author, Nanda A. Singh, from the genetics department at the University of Utah, said in a news release from the university.

The study appears Sept. 18 in the journal PLoS Genetics.

Febrile seizures, the most common form of early childhood seizures, affect about one in 20 North American infants. Though most infants outgrow the problem, some continue to have seizures into adulthood.

Dravet syndrome is a type of epilepsy that begins with febrile seizures. The researchers said their findings suggest that infants with Dravet syndrome should be tested for the SCN9A mutation to determine whether sodium channel blockers should be used to treat their seizures.

SOURCE: University of Utah, news release, Sept. 16, 2009