In the case of the PTGS2 gene, it was noticed that the expression of the most common COX2.1 isoform (NM_000963.3) in the control group was reduced in favor of increased expression of the COX2.2 isoform (AY_151286) in patients with CRSwNP. Here, PTGS2 is linked to chronic rhinosinusitis with nasal polyps.