IL1RL1 and childhood onset asthma: Therefore, we analyzed the association of asthma susceptibility, eosinophilic airway inflammation, and response to inhaled corticosteroid (ICS), with single nucleotide polymorphisms (SNPs) of IL33, IL1RL1, and IL1RAP in Chinese Han children, to investigate the effects of those three gene polymorphisms on the risk of childhood asthma, types of airway inflammation, and ICS response in asthmatic Chinese children.