A New Approach for Sheep Selection
Bio-Rad has developed the TeSeE PrP171 screen test assay for determining PrP polymorphism at position 171.* This method ensures rapid selection of the most prion-resistant animals in a flock of sheep. It is fully adapted to large scale testing conditions and can be used as a complement to existing methods (PCR, sequencing), which generally target limited populations (for example, rams) within sheep genotyping programs.
In sheep, the susceptibility to scrapie is genetically determined by codons 136, 154, and 171 of the gene coding for the prion protein. The information carried by codon 171 predominates over that of codon 136 and codon 154. Codon 171 can carry one of 3 amino acids, arginine (R), glutamine (Q) or histidine (H).
Eradication and Genetic Selection Plan
Because of its economic impact on the sheep industry, more and more countries have started scrapie eradication programs. Those which started systematic culling programs when detecting a scrapie positive case have seen a significant decrease in its prevalence but have never succeeded in fully eradicating the disease.
New programs based on the genetic selection of breeding animals have been initiated in various countries as a supplement to or replacement for animal culling. The cost and time-to-result limitations of the current methods (PCR, mass spectrometry), however, restrict the large scale setup and organization of such programs.
TeSeE PrP171 Screen Test Advantages
- Low cost method
- Fast results
- Easy to use
* In collaboration with the INIA (Instituto Nacional de Investigación y tecnología Agraria y Alimentaria, Madrid, Spain) and the CEA (Commissariat à l'Energie Atomique, Saclay, France).