In the era of genome-wide association (GWA) studies, delineating pathogenic asthma genetic pathways has provided bothchallenges and opportunities. Initial GWA studies on asthma and asthma-like phenotypes provided some successes in termsof ascertaining new potential asthma candidate genes. However, due to asthma having a heterogeneous etiology, replicationsof these genotype–phenotype association studies are generally lacking. Furthermore, genes by environment interactionsare generally not considered when GWA studies are conducted. Therefore, there is a need for extensive collaborations inmulti-disciplinary research fields, including different environments and populations, to investigate the functional importanceof variations in the human genome in relation to asthma pathogenesis.