IRF9 and inflammatory bowel disease: To identify transcriptional drivers of the two IBD-related modules, we performed a transcription factor (TF) enrichment analysis (‘Materials and methods’) and found that ZIC2, SMAD3, REL, FOSL1, and BATF are the top enriched TFs for the genes in HFD_M9 (Figure 4C), while the expression of genes in module HFD_M28 may be regulated by interferon regulatory factors (IRFs, IRF1, IRF2, IRF7, and IRF9) and the signal transducer and activator of transcription families (STAT, STAT2) (Figure 4D).