In this study, we investigated the accuracy of IFN-γ as a host marker detected in supernatants after stimulation of whole blood with M. leprae-specific antigens (LID-1, ML89, ML2044, and ML2028) in an overnight culture assay and compared the IFN-γ marker levels in leprosy and non-leprosy control groups. This evidence concerns the gene IFNG and leprosy.