Integrative Multi-Omics and Experimental Analyses Identify TAPBP as a Key Mediator Linking Genetic Susceptibility to Melanocyte Dysfunction in Vitiligo.

Background: Vitiligo is an autoimmune depigmenting disorder characterized by selective melanocyte loss; however, the specific molecular bridges between genetic risk variants and melanocyte-intrinsic immune vulnerability remain largely unexplored. Objective: To elucidate the molecular link between genetic susceptibility and melanocyte injury in vitiligo by integrating multi-omics data. Methods: We integrated large-scale genome-wide association data (FinnGen R12, n=466,064), expression quantitative trait loci (eQTLgen, n=31,684), and single-cell transcriptomic profiles to identify genes mediating vitiligo susceptibility. Results: Cross-omic analysis identified TAPBP as a top candidate, which is significantly upregulated in lesional melanocytes and core to the antigen-processing network. Functional validation in human melanocytes demonstrated that TAPBP overexpression significantly increased HLA class I expression, suppressed cell proliferation, and induced apoptosis. Transcription factor analysis further identified STAT2 as a key upstream regulator, linking interferon signaling to aberrant antigen presentation. Conclusion: These findings suggest that the STAT2-TAPBP axis enhances melanocyte immunogenicity and vulnerability to cytotoxic attack. Our study provides a novel mechanistic link between genetic variation and immune-mediated destruction, positioning TAPBP as a potential biomarker and a target for precision immunotherapy in vitiligo.