The association between familial hemiplegic migraine-related genes (CACNA1A, ATP1A2, and SCN1A) and both migraine and epilepsy (124), as well as the impact of polymorphisms in pain-related sodium channels SCN9A and SCN10A on migraine chronification (125), have been further elucidated. The gene discussed is SCN9A; the disease is epilepsy.