Taking into account the inhibitory effect of TNFα on tumor cell proliferation [43] and that its pro-tumorigenic properties may rather be invoked by low chronic TNFα production than by an intensive outburst that activates reactive oxygen species and kills malignant cells [55], reduced concentration of TNFα in the tumors should have promoted tumor growth in the distal part of the colon. The gene discussed is TNF; the disease is neoplasm.