The human CACNA2D3 gene is located on the short arm of chromosome 3 at position 3p21.1, a common region of allelic deletion, and has been found to possess a potential tumor suppressor function in multiple tumor types, including gastric cancer (11–13), nasopharyngeal cancer (14), breast cancer (15), renal cell cancer neuroblastoma (16), lung cancer (17), and glioma (18). Here, CACNA2D3 is linked to breast carcinoma.