MAPT and early-onset autosomal dominant Alzheimer disease: Studies have shown that the severity of Alzheimer’s disease has a connection with the degree of neurofibrillary tangles deposition, and most neurofibrillary tangles are caused by abnormal hyperphosphorylation of tau (Šimić et al., 2016; Šimić et al., 2017; Chen Y. et al., 2020b).