MAPT and frontotemporal dementia: CRISPR/Cas9 technology has been widely used not only in HIV-1/AIDS treatment (Chen et al., 2018), but also in other human diseases, such as frontotemporal lobar degeneration with tau inclusions (FTLD-tau) (Jiang et al., 2018), Parkinson's disease (PD) (Zhou et al., 2018) and Duchenne muscular dystrophy (DMD) (Lim et al., 2018),with the characteristics of safe, efficient and simple construction.