PRION PROTEIN HEREDITARY AMYLOIDOSIS - PARENCHYMAL AND VASCULAR

Prion protein (PrP) amyloidosis is a feature of Gerstmann-Straussler-S cheinker disease (GSS) and prion protein cerebral amyloid angiopathy ( PrP-CAA). GSS and PrP-CAA are associated with point mutations of the p rion protein gene (PRNP); there is a broad spectrum of clinical presen tations and the main signs are ataxia, spastic paraparesis, extrapyram idal signs and dementia. In GSS, parenchymal amyloid may be associated with spongiform changes or neurofibrillary lesions; in PrP-CAA, vascu lar amyloid is associated with neurofibrillary lesions. In the two dis eases, a major component of the amyloid fibrils is a 7 kDa peptide, ap proximately spanning residues 81-150 of PrP.