The onset of colitis was determined for each mouse on each sampling day with the disease activity index (DAI), encompassing weight loss, stool consistency, and the presence of blood in stools (Fig. 1B; see also Fig. S1 in the supplemental material), and these results were complemented by determining increases in fecal lipocalin 2 levels (Fig. 1C). This evidence concerns the gene LCN2 and colitis.