Neuropathology of Gerstmann-Sträussler-Scheinker disease

Gerstmann-Sträussler-Scheinker disease is a familial neurodegeneration characterized clinically by adult-onset ataxia, postural abnormalities, and cognitive decline, and pathologically by amyloid deposits mostly localized in the cerebral and cerebellar cortices and the basal ganglia. The disease is due to mutations in the prion protein gene. Processing of the mutant proteins originates the amyloidogenic fragments that accumulate in the tissue. PrP-immunoreactive amyloid deposits are the morphological hallmark of the disease. Hypertrophic astrocytes, activated microglia, and nerve cell loss are consistently associated with PrP-amyloid deposits, while spongiosis, diffuse PrP immunoreactivity, neurofibrillary tangles, Lewy bodies, and long fiber tracts degeneration are occasionally associated. The clinical and pathological variability observed in GSS families is related to both mutations and the M/V polymorphism at codon 129 of the mutated gene.