Genome-Wide Association Study of Contrast Media Hypersensitivity in Japanese Patients

Iodinated contrast media (ICM), commonly used in radiological tests such as coronary angiography, can cause hypersensitivity reactions (HSRs). The mechanism of ICM HSRs is thought to be complex; while IgE-mediated allergic reactions appear to be involved, the details remain unclear. This study aims to elucidate the pathogenesis of ICM HSRs through genetic analysis. To date, a few case-control studies have been conducted exclusively on East Asians, but the results have been inconclusive and have not been replicated.We conducted a multistage GWAS for ICM HSRs in Japanese individuals. The study population comprised 153 cases with ICM HSRs (ranging from mild to severe form), 632 controls with no history of ICM-induced allergies, and < 38,721 individuals from the general population. We identified genome-wide significant association signals in the HLA region and also found that these signals originated from the three HLA alleles-B*52:01, C*12:02, DRB1*15:02-previously reported in a Korean candidate gene study. Using instrumental variable analysis with a polygenic score for pediatric asthma (PGS_asthma) as a proxy, we demonstrated that ICM HSRs are associated with the allergic predisposition thought to be shared by asthma and ICM HSRs. There was a significant difference in the distribution of PGS_asthma between ICM HSR patients and non-disease controls (per-SD odds ratio: 1.26, P = 0.021).Our genome-wide approach shows that HLA alleles are among the genetic factors underlying ICM HSRs. Furthermore, it provides evidence for the potential usefulness of predicting the risk of developing ICM HSRs based on allergic predisposition.