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Prion protein codon 129 polymorphism and risk of Alzheimer disease

M Riemenschneider1, N Klopp, W Xiang

  • 1Neurochemistry and Neurogenetics Laboratory, Department of Psychiatry and Psychotherapy, Technische Universität München, Ismaningerstr. 22, 81675 Munich, Germany. m.riemenschneider@lrz.tu-muenchen.de

Neurology
|July 28, 2004
PubMed

Insights

The prion protein gene (PRNP) Met129Val polymorphism is linked to early-onset Alzheimer disease (AD). PRNP Met homozygosity increases risk for Alzheimer disease with earlier onset, suggesting prion protein involvement.

Area of Science:

  • Neuroscience
  • Genetics
  • Medical Research

Background:

  • Alzheimer disease (AD) is a progressive neurodegenerative disorder.
  • The role of the prion protein gene (PRNP) in AD pathogenesis is under investigation.
  • The PRNP Met129Val polymorphism is a common genetic variation with potential disease associations.

Purpose of the Study:

  • To investigate the association between the PRNP Met129Val polymorphism and Alzheimer disease.
  • To determine if PRNP genotype influences age at onset in Alzheimer disease patients.

Main Methods:

  • A case-control study was conducted with 1,393 subjects.
  • Included 482 patients diagnosed with Alzheimer disease and two independent control groups.
  • Genotyping for the PRNP Met129Val polymorphism was performed.

Main Results:

  • PRNP Met homozygosity was associated with an increased risk of early-onset Alzheimer disease (onset ≤ 70 years).
  • The association was significant for patients with onset at 61-70 years (OR=1.72) and ≤60 years (OR=1.92).
  • No significant association was found in patients with onset older than 70 years.

Conclusions:

  • The findings suggest that the prion protein plays a role in the pathogenesis of early-onset Alzheimer disease.
  • PRNP genotype may be a contributing factor to the development of sporadic early-onset AD.
  • Further research is warranted to elucidate the mechanisms underlying this association.

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