Although IFN-g is crucial for Mtb infection protection, some studies have shown that theBCG-induced protection is not only IFN-g-dependent, because BCG-vaccinatedIFN-g-deficient mice challenged with Mtb exhibited better infection control than themice depleted of CD4+ T lymphocytes (Cowley& Elkins 2003, Elias et al. 2005,Abebe 2012). The gene discussed is CD4; the disease is infection.