Recent studies have shown that MAP3K8 has important roles in multiple inflammatory diseases including inflammatory bowel disease (IBD) [10], rheumatoid arthritis (RA) [11], multiple sclerosis (MS) [12], intestinal inflammation [13] and lung inflammation [1, 3, 14]; suggesting that MAP3K8 regulates signalling pathways that are shared amongst the inflammatory diseases. Here, MAP3K8 is linked to rheumatoid arthritis.