Conversely, 6 out of 8 (75%) asymptomatic active TB children were fully capable of responding to HBHA (mean values of IFN-γ 1.01 IU/ml), while 6 out of 36 (16.6%) symptomatic active TB children in vitro responded to HBHA with a mean value of IFN-γ of 0.115 IU/ml (p 0.017). The gene discussed is IFNG; the disease is tuberculosis.