GWAS Reveals Distinct Genetic Architecture of Schistosomiasis-Induced Hepatic Fibrosis with DGKG as a Key Mediator

Schistosomiasis is a major cause of hepatic fibrosis in endemic regions, yet the host genetic determinants of disease progression remain poorly defined. We aimed to identify genetic drivers and underlying mechanisms of schistosomiasis-induced hepatic fibrosis. We performed a genome-wide association study (GWAS) of 984 Schistosoma japonicum-infected individuals from hyperendemic areas in China followed by multi-omics integration and experimental validation to identify causal genes and fibrogenic pathways. Schistosomiasis-associated fibrosis exhibited a genetic architecture distinct from metabolic and viral liver fibrosis, supporting pathogen-specific mechanisms. Eight novel susceptibility loci were identified, including a genome-wide significant signal at 16p13 (rs73575170, P = 3.9 x 10-8). Integrative mapping linked these loci to 262 genes enriched in liver sinusoidal endothelial cells (P = 5.84 x 10-5) and sphingolipid metabolism pathways (P = 4.19 x 10-5). Notably, Diacylglycerol kinase gamma (DGKG, rs6762330, P = 4.37 x 10-6) emerged as a key candidate, with its expression in peri-granuloma and periportal hepatocytes strongly correlating with fibrosis severity (r = 0.816). In vivo, Dgkg knockout attenuated hepatic fibrosis and immunopathology while restoring cholesterol homeostasis, whereas Dgkg overexpression exacerbated fibrogenesis and increased TNF-{beta} levels tenfold. This study identifies DGKG as a key mediator linking lipid metabolism and immune signaling in schistosomiasis-induced fibrosis, uncovering a pathogen-specific genetic mechanism and providing a potential therapeutic target for infection-associated liver fibrosis.