MAPT and Alzheimer disease: Although some samples showed unexpected levels of CSF biomarkers (AD 1, 2: both total and phosphorylated tau lower than AD criteria; Control 1: lower Aβ42 level, marked as * in Table 1), tau/Aβ42 ratios (marked as ** in Table 1), which are known to be more accurate than either of tau and Aβ42 values, were different between the normal control and AD CSF samples (Table 1).