The impact of the bitter taste receptor on the predisposition to chronic rhinosinusitis.

OBJECTIVES

Genetic polymorphisms in bitter taste receptor 2 member 38 (TAS2R38), expressed in the cilia of sinonasal epithelial cells, have been proposed to be contributors to chronic rhinosinusitis (CRS).

METHODS

We assessed the impact of the genetically determined TAS2R38 structure on predisposition to CRS and correlated the expression of the TAS2R38 with haplotypes. 86 patients (60 CRS patients, 26 controls) undergoing nasal surgery were enrolled. PCR to identify single nucleotide polymorphisms in genes encoding TAS2R38 were performed. TAS2R38 expression in sinus mucosa tissues was assessed by immunohistochemistry.

RESULTS

Among CRS patients, the protective genotype PAV/PAV of the TAS2R38 was observed with the lowest frequency. Immunohistochemistry displayed significant overexpression of TAS2R38 in patients with CRS and in those with a non-functional AVI/AVI genotype. Under inflammatory conditions, TAS2R38 was found to translocate from the cell membrane.

CONCLUSIONS

Genetically determined TAS2R38 polymorphisms may influence susceptibility to CRS. The AVI haplotype seems to be an independent risk factor for CRS. Additionally, TAS2Rs and related signalling pathways might create a unique group of therapeutic targets in CRS.