In the process of HIV infections, many factors involved in AD pathology, such as members of Aβ and tau pathways, are regulated by HIV infection, resulting in the accumulation of Aβ plaques or neurofibrillary tangles (NFT) in brains, indicating the similarities and convergences of the two pathologies in AD- and HIV-infected brains. The gene discussed is MAPT; the disease is HIV infectious disease.