FXYD6 encodes a single-transmembrane FXYD domain protein that associates with and regulates sodium/potassium-ATPase (Na,K-ATPase) activity at the plasma membrane 1. The protein reduces the apparent affinity for intracellular Na+ without affecting extracellular K+ affinity, thereby modulating Na,K-ATPase kinetics and potentially regulating its localization 2. FXYD6 is highly expressed in brain regions and plays roles in establishing electrochemical gradients, ion homeostasis, and synaptic function 1. In cancer contexts, FXYD6 expression is dysregulated across multiple malignancies. In glioblastoma, FXYD6+ T cells represent a novel immunosuppressive T cell population involved in tumor immune evasion 3. FXYD6 is downregulated in glioma with hypermethylation at specific CpG sites, serving as a biomarker for diagnosis and prognosis 2. In osteosarcoma, miR-137 suppresses proliferation and migration through FXYD6 targeting 4. In ovarian cancer, FXYD6 overexpression induces ferroptosis, suggesting tumor-suppressive properties 5. Regarding psychiatric disease, FXYD6 association with schizophrenia remains inconsistent across populations. While some studies report associations with specific SNPs and haplotypes in Chinese and family-based cohorts 67, larger population studies in Japanese and Chinese Han populations found no significant associations 18.