Acquired resistance to coccidioidomycosis strongly correlates with the development of a delayed-type hypersensitivity skin test response to coccidioidal antigens [23] and the production of T-helper-1 (Th1)-associated cytokines to coccidioidal antigens, such as interferon-gamma (IFN-γ) and Interleukin-2 (IL-2) [24]. This evidence concerns the gene IFNG and coccidioidomycosis.