It has also been reported that similar differences possibly existed between concentration levels of tau proteins in the blood of AD patients and those of healthy controls.17,18 Such a difference can lead us to expect that development of a blood-based assay will help lower the barrier to opportune AD diagnosis due to the relatively straightforward and cost-effective arrangement of the relevant samples containing tau proteins, as compared to the CSF-based assay. Here, MAPT is linked to Alzheimer disease.