MAPT and primary progressive aphasia: Although there are major subtypes categorized on brain atrophy and tau pathology dissemination—such as minimal atrophy, typical, limbic predominant, and hippocampal sparing—there are also a plethora of differing variants, such as mild dementia, cortical atrophy, corticobasal syndromal, primary progressive aphasia, amyloid positive, and immunosenescent variants [4].