In 4 month-old mice, YFP + Hu+ double-expressing neurons rose in frequency from 1.1 ± 0.6% of all Hu+ cells in controls to 4.4% ± 1.9% following DSS colitis (Fig. 3g; p < 0.05), suggesting that colitis causes Sox2+ cells to give rise to new neurons. The gene discussed is SOX2; the disease is colitis.