During the progression of AD, tau pathology typically begins in the brainstem, including the locus coeruleus (LC), and then progresses to the transentorhinal cortex or the entorhinal cortex in the medial temporal lobe (Braak stages I and II), then to the hippocampal region (Braak stages III and IV), and finally to the neocortex or the primary areas of the neocortex (Braak stages V and VI) [114]. The gene discussed is MAPT; the disease is Alzheimer disease.