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Polymorphisms at codons 141 and 154 in the ovine prion protein gene are associated with scrapie Nor98 cases

Truls Moum1, Ingrid Olsaker2, Petter Hopp3

  • 1Norwegian School of Veterinary Science, Department of Production Animal Clinical Sciences, Kyrkjevegen 332-334, N-4325 Sandnes, Norway.

The Journal of General Virology
|December 18, 2004
PubMed

Insights

Unusual scrapie cases (Nor98) in Norway show a strong association with specific prion protein (PrP) genotypes, particularly a polymorphism at codon 141. This finding differentiates Nor98 from classical scrapie, suggesting a genetic link to this distinct disease form.

Area of Science:

  • Veterinary Medicine
  • Genetics
  • Neuroscience

Background:

  • Unusual scrapie cases, designated Nor98, have been identified in Norway since June 2004.
  • Classical scrapie cases have distinct epidemiological and genetic profiles.

Purpose of the Study:

  • To investigate the prion protein (PrP) genotype distribution in Nor98 scrapie cases.
  • To compare the PrP genotype frequencies between Nor98 cases, their flock-mates, and a general sheep population.

Main Methods:

  • Genotyping of PrP in Nor98 scrapie cases.
  • Genotyping of PrP in control groups including flock-mates and randomly selected slaughtered sheep.
  • Statistical analysis to compare genotype frequencies.

Main Results:

  • Nor98 cases exhibited a significantly different PrP genotype distribution compared to classical scrapie.
  • A leucine/phenylalanine polymorphism at codon 141 was strongly associated with Nor98 cases (52.6% of cases vs. 10.5% of flock-mates and 4.5% of controls).
  • The H(154) allele was also more prevalent in Nor98 cases (63.2%) than in flock-mates (27.0%) and controls (17.0%).

Conclusions:

  • The PrP genotype, particularly at codon 141, is a significant factor associated with the Nor98 form of scrapie.
  • This genetic association suggests a potential role for host genetics in the emergence or susceptibility to Nor98 scrapie.
  • Further research is warranted to understand the implications of these PrP polymorphisms for scrapie pathogenesis.

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