PRNP and myopathy: To test this hypothesis, we took confocal images of frozen skeletal muscle sections from the six myopathy patients and these four controls (Figs. 1a and 2a), and obtained confocal images of C2C12 mouse myoblasts (control) and C2C12 myoblasts stably overexpressing WT PrPC upon differentiation for 4 days (Fig. 2d).