Association of single nucleotide polymorphisms in the F2RL1 gene with clinical and inflammatory characteristics of patients with asthma.

ABSTRACT

BACKGROUND: Proteinase-activated receptor 2 (PAR-2) is a G-protein coupled receptor associated with many inflammatory diseases, including asthma. We have shown an association between PAR-2 expression in peripheral blood monocytes and asthma severity as well as blood PAR-2 mRNA level and lung function. Since F2RL1 (the gene encoding PAR-2) polymorphisms affect PAR-2 expression, we hypothesize they may affect asthma severity. METHODS: We recruited 76 subjects with asthma of varying severity and collected clinical (FEV1 [% predicted], FEV1/FVC, IgE) and immunological (PAR-2 mRNA, blood eosinophils) disease parameters. We also genotyped these individuals for 3 F2RL1 SNPs (-45C/T, -149C/G, c.621C/T). RESULTS: We found that the F2RL1 SNP "C" allele of -45C/T (rs1529505) was associated with PAR-2 mRNA and blood eosinophils. F2RL1 SNP c.621C/T (rs631465) was associated with PAR-2 mRNA. The F2RL1 SNP -149C/G (rs2242991) had no association with any of the parameters studied. This study identified one F2RL1 SNP rs1529505 is associated with parameters of asthma, but not asthma severity. CONCLUSION: Larger studies are needed to further elucidate the role of PAR-2 in the pathophysiology of asthma and the influence of genetic variation.