PRNP and prion disease: In this study, we aimed to update our previous reports on Japanese prion diseases [6,9,18,23], to conduct a replication effort with larger numbers of cases and statistically increased accuracy, and to evaluate the levels of effects of PRNP polymorphisms with odds ratios (ORs) on the onset of comprehensive prion diseases including sCJD, gCJD, dura-grafted iatrogenic CJD (dCJD), and Gerstmann-Straussler-Scheinker disease (GSS) using Japanese surveillance data on prion diseases.