Recently, using a mass spectrometry approach that simultaneously quantifies different P-tau forms, the different phosphorylation sites that are quantified in this study were not phosphorylated to the same degree, with phosphorylation of P-tau181 present to a high degree in plasma and CSF of controls and with a relative small increase in patients with AD, while P-tau217 seems to be phosphorylated to a very low degree in controls, while the increase in AD is high [6, 17]. This evidence concerns the gene MAPT and Alzheimer disease.