The human prion gene M129V polymorphism is not associated with idiopathic Parkinson's disease in three distinct populations.

Coexistence of prion disease and idiopathic Parkinson's disease (IPD) has been previously described. It remains unclear whether this relationship may reflect the high incidence of IPD or whether both prion and IPD share common pathogenetic mechanisms. For this reason, we investigated the genotype distribution of the M129V polymorphism of the human prion gene for association with IPD (controls: n = 398, IPD cases: n = 400). No association between genotypes in codon 129 and IPD was detected in three distinct populations, suggesting that this PRNP polymorphism has no direct influence on the susceptibility to IPD.