Association analysis of ILVBL gene polymorphisms with aspirin-exacerbated respiratory disease in asthma.

BACKGROUND: We previously reported that the ILVBL gene on chromosome 19p13.1 was associated with the risk for aspirin-exacerbated respiratory disease (AERD) and the percent decline of forced expired volume in one second (FEV1) after an oral aspirin challenge test. In this study, we confirmed the association between polymorphisms and haplotypes of the ILVBL gene and the risk for AERD and its phenotype.

METHODS: We recruited 141 AERD and 995 aspirin-tolerant asthmatic (ATA) subjects. All study subjects underwent an oral aspirin challenge (OAC). Nine single nucleotide polymorphisms (SNPs) with minor allele frequencies above 0.05, which were present in the region from 2 kb upstream to 0.5 kb downstream of ILVBL in Asian populations, were selected and genotyped.

RESULTS: In an allelic association analysis, seven of nine SNPs were significantly associated with the risk for AERD after correction for multiple comparisons. In a codominant model, the five SNPs making up block2 (rs2240299, rs7507755, rs1468198, rs2074261, and rs13301) showed significant associations with the risk for AERD (corrected P = 0.001-0.004, OR = 0.59-0.64). Rs1468198 was also significantly associated with the percent decline in FEV1 in OAC tests after correction for multiple comparisons in the codominant model (corrected P = 0.033), but the other four SNPs in hapblock2 were not.

CONCLUSION: To the best of our knowledge, this is the first report of an association between SNPs on ILVBL and AERD. SNPs on ILVBL could be promising genetic markers of this condition.