SCN2A and autism: One gene that has come to light as an important molecular cause of both epilepsy and autism is Scn2a, which encodes neuronal Nav1.2 voltage‐gated sodium channel α‐subunits that regulate action potential initiation and propagation in axons and action potential backpropagation in somatodendritic compartments (Hu et al., 2009; Spratt et al., 2019).