Dopamine transporters (DAT) uptake neurotoxic substances such as 1-methyl-4-phenylpyridinium (MPP+) in the dopaminergic nerve terminals and may confer susceptibility to cytotoxic effects of neurotoxic substance. The association of a variable number tandem repeat polymorphism in the DAT gene with Parkinson's disease (PD) in a Korean population was studied. The 10-copy allele was the most common, accounting for 77.2% and 81.6% of alleles in PD patients and control subjects, respectively. The rare 11-copy allele was more common in the patients (odds ratio = 2.5, 95% confidence interval = 1.1-5.7, p<0.02). It is suggested that the 11-copy allele of the DAT gene may confer susceptibility to PD for some patients in Korea.