A synonymous variation in protease-activated receptor-2 is associated with atopy in Korean children.
J Allergy Clin Immunol 2011;
128:1326-1334.e3. [PMID:
21839502 DOI:
10.1016/j.jaci.2011.06.036]
[Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 06/25/2011] [Accepted: 06/28/2011] [Indexed: 11/20/2022]
Abstract
BACKGROUND
Atopic diseases are the most common chronic diseases of childhood, and the genetics of atopy are complex and heterogeneous. Protease-activated receptor-2 (PAR-2) is involved in various inflammatory diseases, but the association of PAR-2 with allergic diseases remains unclear.
OBJECTIVE
To examine the contribution of genetic variation of PAR-2 to atopic phenotypes in the Korean childhood cohort.
METHODS
We identified PAR-2 variations in a Korean population and conducted association analyses by using 316 unrelated atopic and 210 nonatopic subjects. We analyzed serum IgE and total eosinophil count levels and examined PAR-2 mRNA and protein expression levels.
RESULTS
In the case-control association analysis, atopy was significantly associated with a single c.621C>T (p.I207I, rs631465) polymorphism of PAR-2 (P = .001, odds ratio = 1.95). Subjects with the c.621T risk allele had significantly higher serum IgE (P = .004) and total eosinophil count (P = .03) levels. Moreover, the positive association of c.621T was reproduced in the replication study (P = .01, joint P value of the replication < .001). An in silico analysis of RNA secondary structure prediction revealed that the C to T conversion at c.621 greatly increased predicted PAR-2 mRNA stability. This was also confirmed by an in vitro assay for mRNA stability. Furthermore, following an in vivo approach on gene expression in PBMCs showed that the expression levels of PAR-2 mRNA and protein in subjects with the c.621CT or TT genotype were significantly higher than in those with the c.621CC genotype.
CONCLUSIONS
These results indicate that the synonymous c.621C>T polymorphism in PAR-2 might be associated with the risk of atopy, potentially by altering PAR-2 gene expression.
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