Genotype imputation of SNP genotype data
The genotype imputation was performed using the Michigan imputation server (https://imputationserver.sph.umich.edu). We used Haplotype Reference Consortium release v1.1 and considered only ‘non-European’ or ‘mixed’ population16. Pre-phasing and imputation were performed using Eagle V 2.417 and Minimac418, respectively. After the imputation processes, imputed SNPs were removed if the Rsq was less than 0.3, or there were duplicated SNPs, missing genotype rates were larger than 0.05, P values in HWE tests were less than 1×10-5, or MAFs were less than 0.05. In addition, subjects whose identity-by-descent (IBS) > 0.9 and principal component (PC) score was outside the 5×IQRPC were excluded. Finally, 1,386 asthmatic patients and 5,205 controls and their 4,935,875 SNPs were used for our analyses. The detailed procedure is shown in Figure E1.