Decreased ASL height also contributes to increased mucus viscosity (KE5), a phenomenon that is well described in cystic fibrosis, where CFTR defect results in decreased ASL height, leading to decreased MCC (KE7) and subsequent mucus plugging (Birket et al., 2014; Birket et al., 2016; Birket et al., 2018). The gene discussed is CFTR; the disease is cystic fibrosis.