As higher concentration of IL-4 is also found in aged individuals due to dysregulation between Th1 and Th2, [44] this synergistic elevation in IL-4 secretion may contribute to increased pathogenesis in diabetic TB patients because IL-4 impairs anti-microbial activity of infected cells and increases availability of iron to intracellular M. tuberculosis. The gene discussed is IL4; the disease is tuberculosis.