Despite this serological and clinical heterogeneity, 6 of the 9 (67%) patients with cryptogenic epilepsies had Kv1.2-specific antibodies, both patients with neuropathic pain had Kv1.6 reactivities, and both patients with small cell lung carcinoma had antibodies directed against all three subunits (Kv1.1, Kv1.2 and Kv1.6). This evidence concerns the gene KCNA2 and small cell lung carcinoma.