The interleukin 1 receptor-like 1 gene (IL1RL1) has been considered in numerous genome-wide association studies (GWASs) as a gene for asthma susceptibility, response to inhaled corticosteroids (ICS), and the significant increase in serum IgE [12,13,14,15,16], and could affect the response to omalizumab. The gene discussed is IL1RL1; the disease is asthma.