Genome-wide association study (GWAS)
Genome-wide association analysis of recurrent wheeze and asthma diagnosis used a logistic regression model, adjusted for sex and three significant PCs using Plink 1.9.(23) All variants with minor allele frequencies (MAF) less than 1% in the population were filtered out due to the lack of statistical power for detecting associations with rare variants. For significantly associated SNVs, local plots of recombination rates were visualized using LDassoc function of the LDlink web application.(30) Manhattan plots and quantile-quantile (qq) plots of GWAS analysis were generated using the qqman package in R.(31)