The AA% ranged from 50.6% to 100%, and also showed a correlation with VCI (r = 0.566, p = 0.044) and WMI (r = 0.649, p = 0.016), but less consistently when compared to the TM score.<h4>Conclusions</h4>Structural preservation of CaV2.1 correlates more strongly with intellectual function in patients with EA2 than protein length, which suggests that structural disruption of the CaV2.1 channel may contribute to cognitive impairments in EA2. The gene discussed is CACNA1A; the disease is Cognitive impairment.