PRNP and infection: We further conclude that whereas the overlapping effects of PrP residue 226 variation on the propagation of NA moose, deer, and elk CWD prions are consistent with infection by strains with shared properties, the distinct responses of NO moose CWD prions to variation at residue 226 indicates that the strain characteristics of these emergent CWD prions are different from those of established NA CWD.