The low-risk group was remarkably correlated with infection, immune response, immune rejection, autoimmune disease, apoptosis, immune globulin, cytokine, chemokine, complement and other signaling pathways (e.g. T cell receptor, B cell receptor, Toll-like receptor, JAK-STAT, PPAR, MAPK, VEGF pathways). The gene discussed is PPARA; the disease is infection.