MAPT and early-onset autosomal dominant Alzheimer disease: Alzheimer’s Disease Assessment Scale cognitive subscale (ADAS-Cog) Mini-mental state examination (MMSE) Controlled oral word association test (COWAT) Category fluency test (CFT) Cogstate computerized battery Structural and diffusion-weighted MRI FDG-PET (glucose metabolism) Biomarker analysis (β-amyloid, total and phosphorylated tau)