Whether this tonic phase apnea occurs in instances of clinical SUDEP is unclear; however, some epilepsies that commonly present with frequent tonic seizures (e.g., tuberous sclerosis complex, Lennox-Gastaut syndrome, and SCN8A EE) do also experience higher mortality rates, often from SUDEP (Autry et al., 2009; Gardella and Møller, 2019; Parthasarathy et al., 2021). This evidence concerns the gene SCN8A and tuberous sclerosis.