The G209A mutation in the alpha-synuclein gene is not detected in familialcases of Parkinson disease in non-Greek and/or Italian populations

Objective: To determine whether the G-to-A substitution at nucleotide 209 ( G209A) mutation in the alpha-synuclein gene is responsible for familial Par kinson disease (PD) in the US population. Design: Polymerase chain reaction-based DNA analysis of consecutive patient s with PD and family history of PD. Setting: A university-affiliated movement disorder clinic and a Veterans Af fairs clinical research laboratory. Patients: Forty-four patients with PD and family history of PD and 29 patie nts with sporadic PD, all with no known Greek and/or Italian background. Results: None of the DNA samples showed the G209A mutation. Conclusion: The G209A mutation is rare in US patients with familial PD.