As shown in Figure 2, a positive correlation (P<0.05) between the relative frequency of the Faecalibacterium genus (Firmicutes Phylum, Clostridium GroupIV) and mRNA expression levels of Paneth cell genes, including DEFA5 and DEFA6, was observed in ileal CD patients but not in non-IBD controls or UC patients. This evidence concerns the gene DEFA5 and inflammatory bowel disease.