The First Meta-Analysis of the M129V Single-Nucleotide Polymorphism (SNP) of the Prion Protein Gene (PRNP) with Sporadic Creutzfeldt-Jakob Disease.

Prion diseases are fatal, chronic, and incurable neurodegenerative diseases caused by pathogenic forms of prion protein (PrPSc) derived from endogenous forms of prion protein (PrPC). Several case-control and genome-wide association studies have reported that the M129V polymorphism of the human prion protein gene (PRNP) is significantly associated with susceptibility to sporadic Creutzfeldt-Jakob disease (CJD). However, since some case-control studies have not shown these associations, the results remain controversial. We collected data that contain the genotype and allele frequencies of the M129V single-nucleotide polymorphism (SNP) of the PRNP gene and information on ethnic backgrounds from sporadic CJD patients. We performed a meta-analysis by collecting data from eligible studies to evaluate the association between the M129V SNP of the PRNP gene and susceptibility to sporadic CJD. We found a very strong association between the M129V SNP of the PRNP gene and susceptibility to sporadic CJD using a meta-analysis for the first time. We validated the eligibility of existing reports and found severe heterogeneity in some previous studies. We also found that the MM homozygote is a potent risk factor for sporadic CJD compared to the MV heterozygote in the heterozygote comparison model (MM vs. MV, odds ratio = 4.9611, 95% confidence interval: 3.4785; 7.0758, p < 1 × 10-10). To the best of our knowledge, this was the first meta-analysis assessment of the relationship between the M129V SNP of the PRNP gene and susceptibility to sporadic CJD.