The same group also described a serum immunologic profile for patients with refractory tonic-clonic seizures, characterized by increased levels of IL-6, low levels of IL-1Ra and low IL-1Ra:IL-1β ratio, with no evidence of corresponding increase in the production from peripheral blood mononuclear cells suggesting the origin of these cytokines to be within the brain (Lehtimäki et al., 2004, 2010). This evidence concerns the gene IL6 and Bilateral tonic-clonic seizure.