Thus, we found significant interactions of diet and infection for several genes, especially those related to the mucosal barrier (Table 5), such as DCLK1, HDAC9, IL13RA1, MUC2 and HDAC1 (Fold change 2.5, 1.9, 1.3, 1.3 and − 1.2, respectively). The gene discussed is HDAC9; the disease is infection.