Neuroimaging studies that examined the biomarkers of early AD (accumulation of global Aβ and tau burdens) in SMC individuals have found an increased accumulation of early tauopathy in the entorhinal cortex (Buckley et al., 2017) as well as an increase in global Aβ burden (Rodda et al., 2010; Amariglio et al., 2012); both are considered neuropathological hallmarks of AD (Braak and Braak, 1997). This evidence concerns the gene MAPT and Alzheimer disease.