PPARA and rheumatoid arthritis: KEGG enrichment analysis showed the most significant pathway including Chemical carcinogenesis-DNA adducts, Hematopoietic cell lineage, Retinol metabolism, Drug metabolism-other enzymes, Cytokine-cytokine receptor interaction, TNF signaling pathway, Lipid and atherosclerosis, Drug metabolism-cytochrome P450, Osteoclast differentiation, Rheumatoid arthritis, Fat digestion and absorption, Bile secretion, PPAR signaling pathway, et al.