Personalization of treatment is done testing biomarkers such as calprotectin (Cal), serum C-reactive protein (CRP), fecal lactoferrin (Lf) and polymorphonuclear neutrophil elastase (PMN-e), especially used to differentiate IBD patents from those with irritable bowel syndrome (IBS) [7]. The gene discussed is ELANE; the disease is irritable bowel syndrome.