Levels of Aβ42, Tau and P-Tau in the cerebrospinal fluid (CSF) are correlated with senile plaques and neurofibrillary tangles: low levels of Aβ42 and high levels of Tau and P-Tau are typical but not restricted to AD, though these changes differentiate patients with AD from normal subjects or patients with other neurologic conditions with high accuracy [36,37]. The gene discussed is MAPT; the disease is Alzheimer disease.