Asthma is a disease with demonstrated heritability in humans, and several genes, including the IKZF3-ZPBP2-GSDMB-ORMDL3 locus, HLA-DQ, IL1RL1, IL33, TSLP, SLC22A5, SMAD3, and RORA have been consistently associated with asthma in genome-wide association studies (GWAS) [8,9]. This evidence concerns the gene IL33 and asthma.