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Polymorphism of PRNP codons in the normal Icelandic population

G Georgsson1, T Tryggvason, A D Jonasdottir

  • 1Institute for Experimental Pathology, University of Iceland, Reykjavik, Iceland. ggeorgs@hi.is

Acta Neurologica Scandinavica
|May 6, 2006
PubMed
Abstract

Insights

Prion protein gene polymorphisms, like methionine-methionine (MM) at codon 129, influence prion disease risk. This study examined these common genetic variations in healthy individuals to understand their prevalence.

Area of Science:

  • Neurogenetics
  • Human Genetics
  • Molecular Biology

Background:

  • Prion protein gene (PRNP) polymorphisms significantly impact human susceptibility and disease phenotypes, including Creutzfeldt-Jakob disease (CJD).
  • Methionine-methionine (MM) homozygosity at PRNP codon 129 is a known risk factor for sporadic CJD.
  • Variations at codon 117 and octapeptide repeat regions are linked to genetic CJD forms.

Purpose of the Study:

  • To investigate the frequency and distribution of key prion protein gene polymorphisms in a healthy European population.
  • To establish a genetic baseline for PRNP codon 129, codon 117, and octapeptide repeat variations.
  • To assess potential gender or age-related differences in these common genetic markers.

Main Methods:

  • Genotyping of 208 healthy blood donors for PRNP polymorphisms at codons 129 and 117.
  • Analysis for the presence of octapeptide repeat deletions.
  • Statistical evaluation of polymorphism frequencies across different demographic groups.

Main Results:

  • Codon 129 polymorphism frequencies: MM (46.6%), MV (44.7%), VV (8.7%).
  • Codon 117 polymorphism observed in 4.8% of individuals; no octapeptide repeat deletions detected.
  • No significant gender or age-related differences in codon 129 polymorphism distribution were found.

Conclusions:

  • The observed frequencies of PRNP codon 129 polymorphisms in this healthy cohort align with general European populations.
  • This data provides valuable genetic background information on prion protein gene variations in healthy individuals.
  • Understanding the prevalence of these polymorphisms is crucial for interpreting their role in prion disease pathogenesis.

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