The main objectives of the work were identification of known and new, so far undescribed in human, transcriptional variants of PTGS1 and PTGS2 genes in CRSwNP patients and in the control group of healthy individuals; analysis of examined isoforms expressions in aspirin tolerant and intolerant patients with CRSwNP; determination of the relationship between the expression of transcript variant of PTGS1 and PTGS2 gene and the clinical course of CRSwNP. Here, PTGS1 is linked to chronic rhinosinusitis with nasal polyps.