Find here the conclusions based on all research performed in the GoatBSE project as far as the data were available. Experiments were still runing when closed in 2013. Now in 2015 the picture is more completre while still new goat experiments are running in the GOAT-TSE-FREE project period.
In another study of Aguilar-Calvo, goats with the 222K prion protein (PrP) codon appeared relatively highly resistant to oral infection with experimentally derived goat BSE. While wild type goats or 211Q/R goats showed positivity inside brain tissue by immunohistochemistry (microscopy), the 222Q/K goats remained negative. Also when tested for infectivity using the highly BSE-sensitive mouse line Tg110, the wild type and 211Q/R animals became before 37 months after infection clinically ill and appeared PrPSc positive in brain and peripheral tissues. However, very low infectivity was detected in the brain from only one of the two 222Q/K goats euthanized at 44-45mpi; the animals appeared still healthy. Also, only sub-base line traces of infectivity were detected in the eye muscles from both goats, thus suggesting that 222K PRNP variant drastically decreases the susceptibility of goats to goat derived BSE. These results demonstrate that transmission of goat-BSE is genotype dependent and highlight the pivotal protective effect of the 222K PRNP variant in the oral susceptibility of goats to BSE.
Italian researchers present the first ever experimental evidence of scrapie resistance in goats carrying the prion protein PRNP allele 222K.
In their paper “Role of the Goat K222-PrPC Polymorphic Variant in Prion Infection Resistance” Aguilar-Calvo and others show that transgenic mice expressing the wildtype (222Q) PRNP allele were fully susceptible to infection with all tested TSE isolates, whereas transgenic mice expressing similar levels of the 222K allele were resistant to all goat scrapie and cattle BSE isolates. However, these 222K mice are not resistant to goat derived BSE. However, the occurrence of goat BSE would be a very improbable condition. All the results presented support the view that the K222 polymorphic variant is a good candidate for selective breeding programs to control and eradicate scrapie in goat herds.