SMAD1 and asthma: The cluster change in the expression of groups of TGF‐β–Smad signaling pathway genes, studied in asthmatic patients (cluster 1: TGF‐β1 and Smad7, and cluster 2: TGF‐β3, MPK1/3, Smad1/3/6), may be a reason for clustering genetic elements into asthma phenotypes and conducting a deeper analysis of the similarity of interactions between different groups of proteins involved in the chronic inflammatory process.