Levels of T-tau were lower in iNPH compared with all other groups, p < 0.001, while levels of amyloid beta 1–42 (Aß-42) were lower in iNPH than in controls, FTD, and MCI (p < 0.01, < 0.001 and < 0.001, respectively) but higher in iNPH than in patients with AD and MCI/AD (p < 0.001), see Table 1. This evidence concerns the gene MAPT and Alzheimer disease.