SPTAN1-related disorders comprise a wide spectrum of neurodevelopmental phenotypes ranging from mild to severe form. It is reported that SPTAN1 is a genetic cause of neurodevelopmental disorders, with three phenotypic subgroups. Typical variants of this gene show severe form of developmental and epileptic encephalopathy (DEE) with progressive brain atrophy (OMIM #613477, DEE5). The second group manifests milder phenotypes of developmental delay (DD) / intellectual disability (ID) with or without child-onset epilepsy. The final group accounts for the patients with hereditary spastic paraplegia (HSP) and ataxia.
Accurate prevalence is not available at present, and fewer than 100 cases were reported worldwide to date. Most variants are heterozygous variants but occurred de novo. Variants in some families with HSP or motor neuropathy are reported to be inherited. Rarely, autosomal recessive HSP with SPTAN1 missense variants were reported in two families.
SPTAN1