Both the six gene signature (6GS: CPA3, DNASE1L3, CLC, IL1B, ALPL, and CXCR2) and T‐helper 2 signature (TH2S: CLCA1, SERPINB2, and POSTN) are proposed as biomarkers in the identification of inflammatory phenotypes of asthma in induced sputum and epithelial brushings, respectively. Here, CLCA1 is linked to asthma.