Additionally, several large-scale studies have failed to detect significant CLCN2 mutations in cohorts of patients with IGE or other epilepsy syndromes (Blanz et al., 2007; Everett et al., 2007; Stogmann et al., 2006), and the causal role of CLCN2 mutations has been questioned by several authors, further complicating our understanding of the role of the gene in epilepsy. The gene discussed is CLCN2; the disease is epilepsy.