Although PAS staining demonstrated that mucin was more highly expressed in the epithelia and submucosal glands of the CRSwNP and CRSsNP patients in comparison with mucosa isolated from the control subjects without CRS, respectively (P < 0.05), the expression levels were not statistically significant between the groups (Figure 1). The gene discussed is MUC5AC; the disease is chronic rhinosinusitis without nasal polyps.