Fig. 4.

Western blot PrP^resR136S profile in fresh-frozen tissue of the index patient. In contrast to typical sCJDMM1 (lanes 12 and 15), PK-treated tissue homogenates from different brain regions (lanes 3–9: frontal cortex (3), temporal cortex (4), parietal cortex (5), occipital cortex (6), hippocampus (7), thalamus (8), cerebellum (9)) of the index patient show the association of a low molecular weight fragment of ~ 8 kDa with less defined upper bands in the ~ 21–30 kDa range. After de-glycosylation with PNGase F (lanes 10 and 11), the ~ 8 kDa is unchanged. In contrast, the upper bands merge in a single band of ~ 21 kDa migrating slightly above the unglycosylated fragment of PrPSc type 1 detected in sCJDMM1. Lanes 1 and 2 show a brain homogenate from a control with (1) or without (2, PrP^C profile) PK digestion. The comparison between the PrP^Sc profiles of the index patient and a GSS patient carrying the P102L mutation, in which only the hallmark ~ 8 kDa peptide is seen, is shown in lanes 13 and 14