SCN1A and Febrile seizure (within the age range of 3 months to 6 years): Pathogenic variants of the SCN1A gene result in a wide range of disease severities, from severe DS, on one end of the spectrum, to milder pathologies on the other end, such as genetic epilepsy with febrile seizures plus (GEFS+) and the genetic syndrome with febrile seizures (FS or FS+) (5–8).