After obtaining the end point ThT fluorescence levels of sTau-SA of 4 cases each from AD, PSP, CBD, PiD and NC with 4RCF or 3RCF as the substrate (Fig. 6A, B), we then ran FTA with their corresponding end products, followed by probing the dot-blots with anti-4R tau antibody (RD4) (Fig. 6C) and anti-3R antibody (RD3) (Fig. 6D). This evidence concerns the gene RD3 and Alzheimer disease.