Alterations of the middle ear are results of infections and inflammation and include thickening of the middle ear epithelium with fibrous polyps, increased levels of mucin-secreting goblet cells, over-ossification at the round window ridge, thickened and over-calcified stapedial artery, fusion of malleus and incus, and tympanosclerosis. The gene discussed is MUC5AC; the disease is tympanosclerosis.