Co-localisation studies of abnormal PrP (Alexa 546, red) with Neurofilament (A, C, E, G, I) or with myelin basic protein (B, D, F, H, J), (green, Alexa 488) in the white matter of the frontal lobe. A, B, 4OPRI mutation shows the neurofilament signal being located beside abnormal PrP (A, A’), whereas there is an overlap between MBP and PrP signal (B, B’). C, D; 6OPRI with filamentous PrP being localised next to Neurofilament (C, C’) but directly congruent with MBP (D, D’). E, F there is little white matter PrP in this example of a P102L mutation, whilst a case with an A117V mutation (G, H) shows abundant white matter PrP, which shows PrP immunoreactivity next to neurofilaments, (G, G’) and co-localises with MBP, resulting in yellow signal (H, H’). The more C-terminal mutations, such as D178N show mostly granular PrP deposits and no strong filamentous PrP (I, J). Scale bar 16μm for A-J and 4 μm respectively for A’-J’.