TNF and rheumatoid arthritis: The study conducted by Pauley et al. [27] showed that although the level of miRNA-146a differed between RA and controls, the two main genes responsible for the regulation of TNF-α levels, interleukin-1 receptor-associated kinase 1 (IRAK1) and TNF receptor-associated factor 6 (TRAF6), did not show significant differences in expression between the groups.