TPH1 and laryngotracheoesophageal cleft: In healthy subjects, TPH1 expression in colonic mucosa was 1.19 ± 0.41; in patients with UC, it was 2.71 ± 0.97 (p < 0.001); and in patients with LC, it was 2.38 ± 0.64 (p < 0.001, Figure 1).