Mucin 1 (MUC1) is one of the transmembrane mucins, with a heavily glycosylated extracellular domain that extends up to 200–500 nm from the cell surface, highly expressed in malignant cancers such as breast, ovarian, lung, pancreatic and prostate cancers [183,184,185]. The gene discussed is MUC1; the disease is Familial prostate cancer.