Average serum IL-17 protein values for the four groups (CHB, LC, PHC, and CLF) were 38.9 ± 11.34 pg/ml, 63.9 ± 18.82 pg/ml, 46.8 ± 14.39 pg/ml, 44.0 ± 3.78 pg/ml, respectively, while the control group value was 28.2 ± 7.78 pg/ml. The gene discussed is IL17A; the disease is laryngotracheoesophageal cleft.