IFNG and tuberculosis: The most widely used immunological tests, such as the tuberculin skin test (TST) and the first-generation Interferon-gamma release assays (IGRAs, such as the QuantiFERON-TB Gold in Tube (QFT-GIT) and the T-SPOT.TB), although useful and effective in detecting specific immune responses, cannot distinguish within the complex and wide spectrum of TB infection and such these assay do not have prognostic value [8–12].