CACNA1A and familial or sporadic hemiplegic migraine: Several neurological disorders including familial hemiplegic migraine type 1 (FHM1), a rare monogenic form of migraine with aura, are caused by mutations in the CACNA1A gene, which encodes for the α1A pore-forming subunit of CaV2.1 channels (Ophoff et al., 1996; de Vries et al., 2009; Pietrobon, 2010).