In addition, mucin-related tumor markers have been widely used in clinical practice, for example, MUC16 (CA125) has been widely used as a marker for ovarian cancer; SLea (also called CA19-9) is a marker for pancreatic cancer; MUC1 (CA153) is a biomarker for breast cancer [110,111,112]. The gene discussed is MUC5AC; the disease is familial pancreatic carcinoma.