Furthermore, we should also consider that genotype–phenotype relationships are complex: variable phenotypes can arise from different mutations occurring in the same gene, as exemplified by mutations in SCN1A, where the phenotypic spectrum can range from generalised epilepsy with febrile seizures plus (GEFS +) to Dravet syndrome [11]. Here, SCN1A is linked to encephalopathy, progressive, early-onset, with brain edema and/or leukoencephalopathy.