While much about these processes and the mechanisms by which they support immunity remains unclear, the importance of IRG functions are underscored by the existence of variants in the human IRGM gene that are associated with increased susceptibility to Mycobacterium tuberculosis[4, 5], sepsis[6], non-alcoholic fatty liver disease[7], ankylosing spondylitis[8], and Crohn’s Disease (CD). The gene discussed is IRGM; the disease is Crohn disease.