Secondly, PD interventions deploying CaV1.3 antagonists could be improved in the following aspects: (1) specificity, for which genetically-encoded CMI-based inhibitors provide the desired specificity intrinsic to CaV1 channels; (2) assurance of Ca2+ reduction, for which CMI is mechanistically guaranteed to reduce Ca2+ influx; however, certain antagonists may not be able to provide such assurance due to aforementioned reasons. This evidence concerns the gene CACNA1D and Parkinson disease.