Susceptibility to prion infection of myc-Prnp expressing cells, inferred from the number of PrPSc-positive cells following infection with RML prions, increased in the order G30 PrP, G45 PrP to G70 PrP, while Q90 PrP was refractory to infection (Fig. 6B). The gene discussed is PRNP; the disease is infection.