Age-related defects in murine T cell anti-tumor function have also been reported, these include; reduced numbers of tumor-antigen-specific T cells, decreased proliferative capacity, impaired cytotoxic activity, and reduced production of effector cytokines, such as interferon (IFN)-γ and IL-2, in elderly tumor-bearing mice (10–18). The gene discussed is IFNG; the disease is neoplasm.