CACNA1A and familial hemiplegic migraine: Pathogenic, heterozygous variants in the CACNA1A gene, which encodes the alpha-1 subunit of a voltage-gated P/Q-type calcium channel, are known to be involved in a heterogeneous spectrum of autosomal-dominant, neurological disorders such as episodic ataxia type 2 (MIM# 108500), spinocerebellar ataxia type 6 (MIM#183086), familial hemiplegic migraine with or without progressive cerebellar ataxia (MIM#141500), and a developmental and epileptic encephalopathy (MIM#617106) (1, 2).