ATP2C2 encodes SPCA2, a P-type ATPase that transports calcium and manganese ions into the Golgi lumen, essential for protein processing and secretory pathway function 1. The pump operates through ATP-driven conformational changes, acquiring cytoplasmic ions and delivering them to the Golgi lumen 2. Beyond ATP-driven transport, ATP2C2 mediates store-independent calcium influx by interacting with the ORAI1 channel at the plasma membrane, potentially facilitating transepithelial calcium transport in mammary epithelial cells for milk secretion 3. Clinically, ATP2C2 variants are implicated in neurodevelopmental disorders. A rare missense variant associates with language impairment at higher frequency (1.8%) in affected individuals compared to controls (0.9%), with carriers showing reduced performance on reading and language measures 4. Multiple studies confirm ATP2C2's role in specific language impairment, particularly affecting phonological short-term memory through independent genetic effects 5. Beyond language, genome-wide association identified ATP2C2 variants associated with age at cannabis initiation, consistent with calcium signaling's role in substance use pathways 6. In cancer biology, ATP2C2 expression correlates with breast cancer prognosis and tumor microenvironment composition, negatively predicting survival while regulating immune cell infiltration 7. These findings establish ATP2C2 as a multifunctional calcium regulator with significant implications for neurodevelopmental and oncological disease pathways.