CACNA1A encodes the alpha-1A subunit of P/Q-type voltage-gated calcium channels, which mediate calcium entry into excitable cells and regulate synaptic transmission. The channel protein contains domains that enable high-voltage activation and interact directly with presynaptic release machinery proteins syntaxin and SNAP-25, linking calcium influx to neurotransmitter exocytosis 1. Pathogenic CACNA1A variants cause a clinically heterogeneous spectrum of neurological disorders driven by gain-of-function or loss-of-function mechanisms. Disease presentations include developmental delay or intellectual disability (96% of affected individuals), episodic ataxia type 2, familial hemiplegic migraine, epilepsy (55%), autism spectrum disorder (23%), and paroxysmal movement disorders 2. Gain-of-function variants and those affecting the channel's S5/S6 helices associate with greater disease severity and seizure risk, particularly the recurrent p.Val1392Met variant 2. Recent evidence suggests an age-dependent phenotypic progression, with early-onset cases presenting severe developmental phenotypes and older patients developing chr19 cerebellar ataxia alongside episodic manifestations 3. Treatment strategies target paroxysmal symptoms through interval prophylaxis with acetazolamide, flunarizine, topiramate, and 4-aminopyridine, with efficacy reported across treated patients 3. In therapy-resistant hemiplegic migraine, anti-CGRP antibody galcanezumab has shown benefit 3.