The phenotypes of eight patients, six females, and two males, with CACNA1A gene variants, included three patients with SHM1 manifesting as recurrent severe encephalopathy and hemiplegia (patients 1–3), two patients with developmental and epileptic encephalopathy (DEE) (patients 4 and 5), one patient with hemiconvulsion-hemiplegia-epilepsy syndrome (HHE) (patient 6), one patient with epilepsy having atypical absence and tonic-clonic seizures (patient 7), and one patient with EA2 (patient 8). This evidence concerns the gene CACNA1A and Bilateral tonic-clonic seizure.