ATG16L1 and inflammatory bowel disease: The findings suggest that CD-associated ATG16L1 polymorphisms (ATG16L1-T300A, ATG16L1-300) can alter the composition of the microbiota through changes in antimicrobial peptide secretion, but in a study of 313 patients with IBD, IBD-GRS (based on 200 SNPs associated with IBD risk) showed no association with the composition of the microbiota.