Based on the association study data Il1-r1 and Sod1 loci are associated with prion disease incubation time, however, Sod1 has the strongest effect with a mean difference of 17 days between the homozygous genotypes compared to 11 days for the Il1-r1 genotypes, therefore, we only followed up the Sod1 data. Here, SOD1 is linked to prion disease.