Sodium channel protein type 2 subunit alpha

SCN2A encodes a voltage-gated sodium channel subunit that mediates sodium ion permeability across excitable cell membranes, allowing sodium influx according to electrochemical gradients (UniProt: Q99250). The protein is also implicated in regulating hippocampal replay during sharp wave ripples, which are important for memory consolidation.

SCN2A is expressed in neuronal tissues and plays a critical role in neuronal excitability. Mutations in this gene are associated with multiple seizure disorders: benign familial infantile seizures 3 (BFIS3), developmental and epileptic encephalopathy 11 (DEE11), which can progress to West syndrome, and episodic ataxia 9 (EA9), characterized by episodes of ataxia and early-onset seizures with occasional developmental delay and speech problems (UniProt: Q99250).

SCN2A is classified as SFARI Category 1, indicating strong evidence for association with autism spectrum disorder (SFARI Cat 1), and is noted as syndromic. The gene's involvement in neurodevelopmental and epileptic conditions, particularly those presenting with autism-like features and developmental delays, establishes its relevance to autism and related neurodevelopmental disorders.