The phospho-specific antibodies (3C9, 6G12, 7F2, 8G5, 10G12) generated to the AT8 epitope showed higher levels of detection of sarkosyl-insoluble tau in AD samples than our phospho-independent or phospho-selective antibodies (1H5, 2D1, 4A10, 5F2). This evidence concerns the gene MAPT and Alzheimer disease.