Possible role of EMID2 on nasal polyps pathogenesis in Korean asthma patients

Abstract

Abstract Background Since subepithelial fibrosis and protruded extracellular matrix are among the histological characteristics of polyps, the emilin/multimerin domain-containing protein 2 (EMID2) gene is speculated to be involved in the presence of nasal polyps in asthma and aspirin-hypersensitive patients. Methods To investigate the association between EMID2 and nasal polyposis, 49 single-nucleotide polymorphisms (SNPs) were genotyped in 467 asthmatics of Korean ancestry who were stratified further into 114 aspirin exacerbated respiratory disease (AERD) and 353 aspirin-tolerant asthma (ATA) subgroups. From pairwise comparison of the genotyped polymorphisms, 14 major haplotypes (frequency > 0.05) were inferred and selected for association analysis. Differences in the frequency distribution of EMID2 variations between polyp-positive cases and polyp-negative controls were determined using logistic analyses. Results Initially, 13 EMID2 variants were significantly associated with the presence of nasal polyps in the overall asthma group (P = 0.0008-0.05, OR = 0.54-1.32 using various modes of genetic inheritance). Although association signals from 12 variants disappeared after multiple testing corrections, the relationship between EMID2_BL1_ht2 and nasal polyposis remained significant via a codominant mechanism (P corr = 0.03). On the other hand, the nominal associations observed between the genetic variants tested for the presence of nasal polyps in AERD (P = 0.003-0.05, OR = 0.25-1.82) and ATA (P = 0.01-0.04, OR = 0.46-10.96) subgroups disappeared after multiple comparisons, suggesting lack of associations. Conclusions These preliminary findings suggest that EMID2_BL1_ht2 may be a susceptibility marker of inflammation of the nasal passages among Korean asthma patients.