Mutations in prion protein gene (PRNP) may lead to genetic prion disease, which usually has a broad range of phenotypic presentations that overlap with other neurodegenerative dementias. In this study, we screened the PRNP gene to evaluate the frequency of PRNP mutations and their correlations with clinical phenotype in 185 sporadic neurodegenerative dementia cases and 310 control subjects. Samples of DNA from each subject underwent polymerase chain reaction (PCR) amplification and direct sequencing of PRNP. The clinical characteristics of patients carrying PRNP mutations were detailed. We identified five different PRNP mutations in five patients, of which three were novel (S97N, F198V, and R208C) and two were known (D178N-129M and M232R). The rate of PRNP mutation was 2.70% in our sample. Though future studies confirming the correlation between PRNP mutations and clinical phenotype need to be undertaken, PRNP genotyping may be a valuable tool to differentiate between prion disease and other neurodegenerative dementias. (c) 2008 Wiley-Liss, Inc.