There is evidence that male subjects with a clinical picture of action tremor, Parkinsonism, and cerebellar ataxia may have Fragile X premutations (FRAXA). We analyzed FRAXA and FRAXE triplet repeats in 203 male subjects with Parkinson's disease (PD) and 370 healthy controls. No full mutations or premutations at the FRAXA and FRAXE loci were found in the subjects with PD or in the controls. FRAXA allele distribution was similar in patients and controls. FRAXE intermediate alleles (31-60 repeats CCG) were found in 13 of 203 (6.4%) subjects with PD and in only one of the 370 (0.27%) healthy controls (P < 0.001), thus indicating that these relatively large alleles may be associated with PD.