CACNA1I and Ataxia: Interestingly, CACNA1C mechanisms have also been implicated in the survival of young neurons in the hippocampus and forebrains of animal models.51 Another case patient (R211) had a predicted deleterious rare variant (p.Arg111Gly) in the CACNA1I voltage-gated calcium channel gene and presented with a severe migraine and ataxia following head injury.