IRGM and Crohn disease: After a landmark study showing the importance of human IRGM in anti-mycobacterial autophagy (Singh et al., 2006), several genome-wide association studies identified SNPs in the IRGM gene and a deletion polymorphism in IRGM promoter region as being strongly associated with Crohn’s disease (CD) and tuberculosis (Brest et al., 2011, Che et al., 2010, McCarroll et al., 2008, Parkes et al., 2007, Wellcome Trust Case Control, 2007, Craddock et al., 2010).