Based on these mechanisms, several therapy strategies are investigated to alleviate or suppress this neurodegenerative disease, among which DA supplementation with drugs, including l-3,4-dihydroxyphenylalanine (l-DOPA), DA agonist, and monoamine oxidase B (MAO-B) inhibitors [7], is used to inhibit DA breakdown or activate DA receptor. This evidence concerns the gene MAOB and neurodegenerative disease.