CACNA1E and episodic ataxia type 2: Importantly, such strategies that leverage a generalized up-regulation of ‘secondary’ presynaptic Ca2+ channels (CaV2.2 and CaV2.3) in EA2 rather than targeting individual EA2 mutations in the ‘primary’ presynaptic Ca2+ channel (CaV2.1), of which there are more than 100, would have the advantage of being suitable for most EA2 patients.