Both CCA and RA are associated with high circulating levels of pro-inflammatory cytokines, including interleukin 6 (IL-6), granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon alpha (IFN-α), IL-17, and IL-6, are important in joint inflammation and contribute to the production of cartilage-destroying enzymes.9 The gene discussed is IL6; the disease is rheumatoid arthritis.