The alpha-synuclein gene and Parkinson disease in a Chinese population

Objective: To study the Ala53Thr and Ala30Pro mutations of the alpha-synucl ein gene in a large number of Chinese patients with Parkinson disease (PD) as well as controls. Methods: We recruited 183 Chinese patients with sporadic PD, 17 with younge r-onset PD (onset age <50 years), and 7 with PD and a positive family histo ry as well as 227 unaffected Chinese control subjects from the outpatient d epartments of 2 major hospitals in Hong Kong. All subjects were assessed fo r the the diagnosis of PD by a consultant neurologist or geriatrician. Subj ects were interviewed with a standard questionnaire that also questioned fo r family history. Venous blood samples were obtained from the subjects and genomic DNA was extracted and studied for the presence of Ala53Thr mutation in exon 4 and Ala30Pro mutation in exon 3 of the alpha-synuclein gene usin g a polymerase chain reaction restriction fragment length polymorphism meth od. Results: None of the Chinese PD patients or controls had either the Ala53Th r (exon 4) or Ala30Pro (exon 3) mutation of the alpha-synuclein gene. Conclusion: We failed to discover Ala53Thr or Ala30Pro mutations in a large number of Chinese patients with PD and control subjects, adding to the eme rging consensus that variations in the alpha-synuclein gene are associated with PD in few families worldwide.