Lack of association between IRAK2 genetic variants and aspirin exacerbated respiratory disease

Asthma is a global health problem which threatens approximately 300 million patients worldwide. Among them, up to 20 % of the asthma patients are classified as aspirin exacerbated respiratory disease (AERD). Interleukin-1 receptor associated kinase (IRAK2) is associated with necrosis factor kappa B (NF-(DB)-B-0) pathway via interleukin-1 (IL-1) signaling. NF-(DB)-B-0 pathway is known to be involved in asthma development, and several interleukin and IRAK family members have also been reported to be associated with asthma or AERD. Since IRAK2 plays an important role in the asthma etiology, we hypothesized that the genetic variants of IRAK2 may be associated with AERD. This study genotyped a total of 25 common single nucleotide polymorphisms (SNPs) in 163 AERD cases and 429 aspirin-tolerant asthma (ATA) controls. As a result, no significant association was found between the genetic variants of IRAK2 and AERD (P > 0.05). In further regression analysis for the forced expiratory volume in 1 s (FEV1) decline, an important phenotype for diagnosing AERD, although one haplotype (BL1_ht3) showed a nominal association with FEV1 decline (P = 0.04), the significance disappeared after correction for multiple testing (P > 0.05). Despite limitations in our study and need for replications, our results suggest that the genetic variants of IRAK2 might not be associated with AERD and the obstructive symptoms in asthma.