MUC5AC and pulmonary fibrosis: The ΔbHLH variant displayed downregulation of various collagen (COL10A1, COL5A3, COL7A1, COL8A1, COL9A2), integrin (ITGA7), matrix metalloprotease (MMP3, MMP12, MMP24), ADAM metalloproteinase (ADAMTS9, ADAMTS14, ADAMTS15), mucin (MUC19, MUC20), WNT (WNT7B, WNT9A), and other ECM-protein genes (LUM, TNC, ICAM4) resulting in top predicted pathways including “Pulmonary Fibrosis Idiopathic Signaling Pathway”, “Integrin cell surface interactions”, “O-linked glycosylation”, “Collagen degradation”, “Assembly of collagen fibrils”, “Collagen trimerization”, and “ECM organization” (Figure 3I).