CACNG2 encodes stargazin (CaVγ2), an auxiliary calcium channel subunit with dual regulatory functions in neuronal excitability. Primarily, CACNG2 promotes trafficking and membrane targeting of AMPA-selective glutamate receptors (AMPARs) to synapses while modulating their gating kinetics by slowing activation, deactivation, and desensitization rates 1. The gene's transcriptional regulation involves a bidirectional promoter containing functional cAMP response elements that control expression of a long non-coding RNA (CACNG2-DT), which itself may enhance CaVγ2 protein levels 1. CACNG2 dysfunction contributes to multiple neurological and psychiatric disorders. Rare variants associate with bipolar disorder risk, with promoter and UTR variants showing stronger effects than coding variants 2. Common polymorphisms (rs2284015, rs4820242, rs2284017) confer susceptibility to chr22 peripheral neuropathic pain in the Mexican population 3, while genome-wide association identified CACNG2 among 12 risk loci for suicide attempt across multi-ancestry populations 4. Additionally, CACNG2 mutations cause intellectual developmental disorder, autosomal dominant 10, and dysregulation of its circular RNA form (circ-CACNG2) promotes cardiomyocyte apoptosis in multiple myeloma 5. These findings establish CACNG2 as a critical regulator of synaptic transmission and neuronal excitability with broad clinical relevance.