IL17A and rheumatoid arthritis: The top five KEGG pathways were related to immune and inflammatory responses, including antigen processing and presentation (seven genes, Padj = 0.0019), IL-17 signalling pathway (seven genes, Padj = 0.0033), rheumatoid arthritis (six genes, Padj = 0.018), graft-versus-host disease (four genes, Padj = 0.032), and steroid hormone biosynthesis (four genes, Padj = 0.086) (Figure 4).