MAPT and Alzheimer disease: In contrast, multiple studies presented sex differences in the association of APOE-ε4 dosage with tau accumulation, regardless of amyloid levels, in individuals with MCI and AD,54 reporting higher tau load only in women via positron emission tomography55 or via CSF biomarkers.56 Our findings of higher p-tau and total tau levels in female APOE-ε4 carriers are consistent with these studies.