Again, extensively studied SCN1A pathogenic variants provide a good model for this concept, since similar variants could lead both to a Dravet syndrome phenotype and to a Generalized Epilepsy with Febrile Seizure plus phenotype (GEFS+) in two different subjects (44). This evidence concerns the gene SCN1A and encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.