The GSEA analysis provided further insights, indicating that the high-risk group was enriched in pathways such as cytokine–cytokine receptor interaction, hematopoietic cell lineage, intestinal immune network for IgA production, NOD-like receptor signaling pathway, and primary immunodeficiency (Figure 2G), while the low-risk group was enriched in drug metabolism cytochrome P450, fatty acid metabolism, peroxisome, PPAR signaling pathway, and proximal tubule bicarbonate reclamation (Figure 2H). Here, PPARA is linked to inborn error of immunity.