MAPT and Alzheimer disease: To confirm the association between the laterality of Aβ and tau, we performed the same analyses on three independent cohorts – Open Access Series of Imaging Studies (OASIS-3)29, Anti-Amyloid Treatment in Asymptomatic Alzheimer’s Disease (A4)30,31, and Alzheimer’s Disease Neuroimaging Initiative (ADNI)32 – out of which only A+T+ subjects were included (see Supplementary Table S2.9 for demographics).