Introduction
Asthma is a common chronic inflammatory disease of the airways resulting
from the interaction of genetic susceptibility with environmental
exposures across the life course1. Both genetic and
environmental factors contribute to disease risk, with genetic factors
accounting for 35–95% of the susceptibility to progress
asthma2. Genetic risk factors may be useful in
classifying the endotypes of asthma, and genetic studies allow a
structured means of understanding the causes of asthma as well as
verifying targets that can be used to treat the
disease3. Some studies on the genetic associations
with asthma have been conducted, and genome-wide association studies
(GWAS) represent the most powerful approach for identifying genes that
influence asthma4.
The results of GWASs have highlighted the importance of genetic variants
in, or near, genes that are implicated in asthma. Previous studies have
reported 41 regions associated with asthma, providing novel insight into
disease biology3,5,6. However, few GWAS have been
performed for populations of racial and ethnic minorities. Several
studies have reported significant differences in the allele frequencies
of the variants and genetic architecture between European and Asian
populations7. These suggest that genetic associations
with asthma do not consistently replicate across studies because of the
heterogeneity of populations. Therefore, GWAS using different ethnic
populations are needed for a better understanding of the genetic basis
of asthma.
Although many recent GWAS have reported the association of multiple loci
with asthma risk, the effect of genetic variation on asthma
susceptibility in the Korean population has not been elucidated. For the
Korean population, some studies have performed simple replication
analysis and reported the results of GWAS for aspirin exacerbated
respiratory disease (AERD)8,9. However, no studies
have confirmed the genetic susceptibility of asthma using GWAS in the
Korean population. Therefore, the aim of this study was to (1) identify
genetic variants associated with adult asthmatics in the Korean
population, and (2) evaluate whether significant single nucleotide
polymorphisms (SNPs) in the UK Biobank are specifically correlated with
those in Korean asthmatics.