Polymorphisms of SPRN (shadow of prion protein homology) in three breeds of sheep in China.

The key point, which is related to the susceptibility of prion diseases in animals, has been proved to be the prion protein gene (PRNP). However, animals, especially sheep and goats, with the same PRNP genotype are not equally susceptible to the diseases. The finding of SPRN (shadow of prion protein homology) provides a new aspect to understand the diseases as protein of SPRN (Shadoo) has similar neuroprotective function and conserved hydrophobic core with prion protein (PrP). Researchers have made some efforts to demonstrate the relationship between SPRN and PRNP. Stewart's work has shown that SPRN contained an alanine-rich sequence, which is homologous to a hydrophobic core with amyloidgenic characteristics in PrP. Here our work shows that the sheep of Inner Mongolia in China have several haplotypes with the similar results of Stewart and Daude's. However we find a new haplotype in a Sunite sheep, which is not reported by others.