Taken together, the research results demonstrate that dysregulation (i.e., increase) of SLC15A4/PHT1 gene products in the human intestinal epithelial layer is in the framework of GI inflammation, and, particularly, of IBD, leading the way for the assessment of SLC15A4/PHT1 as a marker of inflammation for UC patients. The gene discussed is SLC15A4; the disease is inflammatory bowel disease.