MAPT and early-onset autosomal dominant Alzheimer disease: Lins et al. measured the immunoreactivity of amyloid beta peptide (1–42, Ab42-IR) and tau protein (total tau immunoreactivity (TTIR) in 12 patients with NPH, and compared them with the levels of an equal number of patients suffering from vascular dementia, Alzheimer's disease, Parkinson's disease without dementia and 24 controls [63].