Excessive IL-17A production in the synovial fluid of rheumatoid arthritis patients has been demonstrated to have a role in the progression of the disease (Siloşi et al., 2016) Antibodies targeting IL-17A result in a reduction of clinical symptom severity, further highlighting the importance of aberrant cytokine responses in differing immune microenvironments (Hueber et al., 2010). The gene discussed is IL17A; the disease is rheumatoid arthritis.