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A new PRNP mutation (G131V) associated with Gerstmann-Sträussler-Scheinker disease.
P K Panegyres1, K Toufexis, B A Kakulas
1Department of Neuropathology, Royal Perth Hospital, Wellington Street, Perth, Western Australia 6000. peter.panegyres@rph.health.wa.gov.au
Archives of Neurology
|November 16, 2001
Summary
Gerstmann-Sträussler-Scheinker disease, a rare prion disease, was linked to a novel prion protein gene mutation (G131V). This finding underscores genetic analysis for atypical dementia cases.
Area of Science:
- Neuroscience
- Genetics
- Pathology
Background:
- Gerstmann-Sträussler-Scheinker disease (GSS) is a rare, fatal neurodegenerative prion disease.
- Characterized by progressive dementia and ataxia, GSS typically lacks a family history.
Observation:
- A 51-year-old male patient presented with a 9-year history of dementia and ataxia.
- Neuropathology revealed abundant prion protein amyloid plaques in the cerebellum without spongiform degeneration.
Findings:
- Genetic analysis identified a novel mutation in the prion protein gene (PRNP) at codon 131, resulting in a glycine-to-valine substitution (G131V).
- The patient was homozygous for methionine at codon 129 (129M).
- Proteinase K-resistant prion protein was detected, confirming the presence of abnormal prion protein.
Implications:
- This study describes the first mutation identified in the short, antiparallel beta-sheet domain of the prion protein.
- Highlights the critical role of genetic testing in diagnosing atypical dementia, even without a known family history of neurological disorders.
- Contributes to understanding the genetic basis of prion diseases and their diverse clinical presentations.
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