Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

PrP genotype contributes to determining survival times of sheep with natural scrapie.

Abstract

The PrP genotype and life spans were determined for more than 50 Flemish and Swifter sheep within a single scrapie-affected flock. 83% of the scrapie sheep were homozygous for the PrPVQ allele (polymorphic amino acids at codons 136 and 171 are indicated) and these sheep died from scrapie at a mean age of 25 months. In sheep heterozygous for PrPVQ, development of scrapie was delayed or did not occur. Sheep with at least one PrPAR allele, including PrPVQ/PrPAR sheep, did not develop scrapie. No scrapie sheep were found without a PrPVQ allele. It is concluded that the PrP genotype contributes to determining survival times of sheep with natural scrapie. Additionally, 2 novel sheep PrP allelic variants are described.