TNF-α inhibitors were introduced in therapy two decades ago as treatment against rheumatoid arthritis, but since then new indications have occurred; currently, TNF-α inhibitors are approved for use in ankylosing spondylitis (AS) [1], Crohn’s disease (CD) [2], juvenile idiopathic arthritis (JIA) [3], psoriasis (PSO) [4], psoriatic arthritis (PsA) [5], rheumatoid arthritis (RA) [6], ulcerative colitis (UC) [7], chronic uveitis [8], and others. This evidence concerns the gene TNF and rheumatoid arthritis.