Alzheimer's and MS are associated with deficiencies in the epidermal growth factor receptor family; one member of said family, which bonds to betacellulin, is called ERBB4.
Insufficient ErbB signaling in humans is associated with the development of neurodegenerative diseases, such as multiple sclerosis and Alzheimer's Disease, while excessive ErbB signaling is associated with the development of a wide variety of types of solid tumor. Ligand betacellulin Receptor ErbB-4 + 
