Dale et al. [71] examined the effects of daily supplementation with cod-derived FPH (2.5 g) versus a placebo for six months on serum concentrations of gut integrity markers (intestinal fatty acid binding protein (iFABP), lipopolysaccharide-binding protein (LBP), and zonulin) and pro-inflammatory cytokines (tumor necrosis factor alpha, interferon gamma, interleukin 4, 6, 8, and 10) in irritable bowel syndrome (IBS) patients. This evidence concerns the gene IFNG and irritable bowel syndrome.