The first of these includes several SNPs around IRGM (immunity-related guanosine triphosphatase; the human homologue of the mouse Irgm/Lrg47), the strongest singal being at rs1000113 (P=5.1×10-8). IRGM encodes a GTP-binding protein which induces autophagy and is involved in elimination of intracellular bacteria, including Mycobacterium tuberculosis67. Reduced function and/or activity of this gene would be expected to lead to presistence of intracellular bacteria, consistent with existing models of CD pathogenesis57 and the recent ATG16L1 association64 (see above).
