Two major endotypes are T‐helper type 2 (TH2)‐high asthma, characterized by eosinophilic inflammation and elevated cytokines (IL‐4, IL‐5, IL‐13, IgE), and TH2‐low asthma with neutrophilic or pauci‐granulocytic profiles and corticosteroid‐resistance (Stokes and Casale 2016). The gene discussed is IL5; the disease is asthma.