What is (are) Dravet syndrome ?
Dravet syndrome is a severe form of epilepsy. The condition appears during the first year of life as frequent fever-related (febrile) seizures. As the condition progresses, other types of seizures typically occur, including myoclonus and status epilepticus. A family history of either epilepsy or febrile seizures exists in 15 percent to 25 percent of cases. Intellectual development begins to deteriorate around age 2, and affected individuals often have a lack of coordination, poor development of language, hyperactivity, and difficulty relating to others. In 30 to 80 percent of cases, Dravet syndrome is caused by changes in the SCN1A gene, which is required for the proper function of brain cells.