Despite progress in understanding the epithelial-mesenchymal transition (EMT) in asthma and establishing a theoretical framework, several unresolved questions remain:1) Molecular mechanisms of EMT: While specific signaling pathways, including the TGF-β1, Wnt/β-catenin and sonic hedgehog pathways, are known to be involved in EMT in asthma, the interactions between these pathways, their regulatory networks and the precise mechanisms controlling EMT remain unclear. This evidence concerns the gene TGFB1 and asthma.