PTAFR and chronic rhinosinusitis with nasal polyps: Therefore, this study aimed to evaluate the expressions of genes associated with PAF metabolism, namely those of enzymes involved in PAF synthesis (LPCAT1, LPCAT2, LPCAT3, and LPCAT4) and degradation (PAFAH1B2, PAFAH1B3, and PAFAH2), as well as the gene of the PAF receptor (PTAFR) across subtypes of CRSwNP classified by clinical- or hierarchal-analysis-based classifications.