Mediation analysis identified that CD123 on plasmacytoid DCs (DCs), CD123 on CD62L+ plasmacytoid DCs, CD80 on plasmacytoid DCs, and CD80 on CD62L+ plasmacytoid DCs mediate the causal effect of GDF-15 on NAFLD. The gene discussed is IL3RA; the disease is metabolic dysfunction-associated steatotic liver disease.