Those MCI subjects with positive biomarkers for AD (i.e., amyloid deposition and neural injury markers such as accumulations of intracellular tau or medial temporal lobe atrophy [MTA]) are regarded to be at the symptomatic pre-dementia phase of AD, and are often referred to as “MCI due to AD” (Albert et al., 2011). The gene discussed is MAPT; the disease is Alzheimer disease.