In a study comparing 7 mucinous adenocarcinomas (previously known as mucinous bronchioloalveolar carcinoma (mBAC)) and 27 non-mucinous BAC, higher levels of MUC2, MUC5AC, and MUC6 expression were found in mucinous BAC (26). The gene discussed is MUC5AC; the disease is mucinous adenocarcinoma.