IFNG and Crohn disease: Crohn’s disease mainly manifests as a patchy pattern of an inflammatory process affecting the whole GIT, although it is more common in the terminal ileum and the right colon with enhanced production of T helper 1 (TH1) cytokines such as interleukin (IL)-12, IL-2, IL-1β, tumor necrosis factor alpha (TNF-α), and interferon gamma (IFN-γ) (Boyapati et al., 2015).