CACNB2 encodes the β2 auxiliary subunit of voltage-gated L-type calcium channels, which enhances peak calcium current and modulates voltage-dependent activation and inactivation 1. It facilitates membrane targeting of the channel α1-subunit CACNA1C and may regulate β-adrenergic augmentation of cardiac calcium influx, controlling heart rate and contractile force 23. CACNB2 functions in cardiac action potentials and calcium ion transport across multiple cardiac tissues including atrial and AV nodal cells. Genome-wide association studies identified CACNB2 variants as shared genetic risk factors across five major psychiatric disorders, with pathway analysis supporting pleiotropic effects of calcium-channel signaling genes on psychopathology 4. The CACNB2 rs11013860 polymorphism associates with structural and functional brain abnormalities in bipolar disorder, including altered grey matter volume in emotional processing circuits 56. Clinically, CACNB2 loss-of-function variants cause Brugada syndrome through reduced L-type calcium current and accelerated channel inactivation, responsive to beta-blockers and quinidine treatment 1. Additionally, CACNB2 polymorphisms associate with essential hypertension and elevated blood pressure in children and adolescents, potentially through RAS-MAPK pathway dysregulation independent of calcium channel activity 789.