Background and purpose: Prion protein (PrP) predominantly localized at synapses can modulate neuronal excitability. The prion protein gene ( PRNP) has been considered one of the candidate genes that play a role in seizure susceptibility. A recent study demonstrated that the 129V allele in the PRNP gene was associated with susceptibility to temporal lobe epilepsy (TLE) in female patients in an Italian population. We screened variations in the open-reading frame (ORF) of the PRNP gene and also replicated the association of the M129V polymorphism with TLE in a Han Chinese population. Methods: The M129V polymorphism was genotyped in 320 MTLE patients and 558 non-epilepsy controls. All subjects were Han Chinese. Results: No novel polymorphism in the ORF of the PRNP gene was detected. Differences in the genotype distributions and allele frequencies of this polymorphism between cases and controls were insignificant (P = 0.24). Further analysis with strati. cation of the results by gender or age and analysis of clinical features in relation to M129V genotypes also yielded negative findings. Conclusions: The present study provides evidence that the M129V polymorphism in the PRNP gene is not associated with MTLE in a Han Chinese population.