The outstanding performance of prion RT-QuIC, and the discovery that other proteins involved in neurodegenerative diseases show a seeding-conversion behavior similar to that of PrP, prompted the scientific community to develop an RT-QuIC assay that could detect protein amyloids in more common neurodegenerative diseases such as Alzheimer’s disease (AD) and Parkinson’s Disease (PD) in the CSF of diseased individuals. This evidence concerns the gene PRNP and Alzheimer disease.