Experimental and clinical data suggest that genetic variations in brain-derived neurotrophic factor (BDNF) gene may affect risk for Parkinson's disease (PD). We performed a case-control association analysis of BDNF in three independent Caucasian cohorts (Greek, North American, and Finnish) of PD using eight tagging SNPs and five constructed haplotypes. No statistically significant differences in genotype and allele frequencies were found between cases and controls in all series. A relatively rare BDNF haplotype showed a trend towards association in the Greek (p=0.02) and the Finnish (p=0.03) series (this haplotype was not detected in the North American series). However, given the large number of comparisons these associations are considered non-significant. In conclusion, our results do not provide statistically significant evidence that common genetic variability in BDNF would associate with the risk for PD in the Caucasian populations studied here.