MAPT and Alzheimer disease: Our study aimed to evaluate the integrity of the whole‐brain WM, through diffusion tensor imaging (DTI) parameters, in mild AD and amnestic mild cognitive impairment (aMCI) due to AD (with Aβ42 alteration in cerebrospinal fluid [CSF]) in relation to controls; and possible correlations between those measures and the CSF levels of Aβ42, phosphorylated tau protein (p‐Tau) and total tau (t‐Tau).