Transmission was also attempted using homogenate made from frozen brain tissue from a patient with PRNP mutation, Q227X. This mutation resulted in expression of truncated PrP with one additional amino acid residue compared to the PrP expressed by the Y226X patient. The Q227X patient presented at age 42 with a hypokinetic rigid syndrome, and was diagnosed with frontotemporal dementia . The patient subsequently developed tremors and seizures and mutism, and died 6 years after onset of disease. Neuropathology showed numerous multicentric and unicentric amyloid plaques which stained positive with anti-PrP antibodies. Plaques were not associated with blood vessels, but were mostly in the neuropil in numerous brain regions.