The DRD3 Ser9Gly polymorphism and risk of dyskinesia in Parkinson's disease

Background: Beside duration and dosage of levodopa treatment, genetic predisposition contributes significantly to development of medication related complications in Parkinson's disease (PD), especially dyskinesia. So far, no genetic risk factor was established. As an important candidate, the gene of the dopamine D3 receptor (DRD3) was studied extensively in psychiatric disease, and several groups reported an association of the Ser9Gly polymorphism to antipsychotic induced tardive dyskinesia in severe mental illness. In PD, one study in a small patient sample analyzed DRD3 Ser9Gly and dyskinesia, with negative re…