We have shown that, in HIV-infected children with definite or probable TB in whom the result of an IFN-γ ELISpot assay is positive at presentation, anti-tuberculous treatment is accompanied by a significant decrease in both the magnitude of the IFN-γ response to MTB-antigens and in the proportion of children with a positive ESAT-6 or CFP-10 response following six months of anti-tuberculous treatment. This evidence concerns the gene IFNG and tuberculosis.