We observed that all Msr1+/+, Msr1+/-, and Msr1-/- mice succumbed to prion disease at a similar progression rate (median survival: 179 dpi for Msr1+/+ mice (n = 17), 186 dpi for Msr1+/-(n = 25) and 183.5 dpi for Msr1-/- mice (n = 14), p = 0.99) (Fig. 2a). This evidence concerns the gene MSR1 and prion disease.