Wild-type mice were resistant to M. bovis BCG infection; one out of 14 (93% survival) memTNFΔ1–9,K11E KI mice died, whereas 7 out of 10 (30% survival) memTNFΔ1–12 KI mice succumbed to the infection with loss of body weight, and all TNFR1/TNFR2 −/− and TNF−/− mice died (Fig. 1A, B). The gene discussed is TNF; the disease is infection.