Recent advances in cellular and genetic engineering technology have garnered considerable interest for human disease modelling and cell replacement strategies. We are interested in exploiting new advances in cell reprogramming and gene editing technology to develop a deeper understanding for the basis of neurodegenerative diseases, and ultimately to develop new therapies for these diseases. Recently, our group have developed a novel nanobiotechnology approach to control cell fate of the somatic cells in in vivo brain. This study provides a proof of principle for in vivo reprogramming as a potentially viable and safe therapeutic strategy for the treatment of Parkinson disease (Nature Nanotechnology, 2017). Moreover, our group developed CRISPR/Cas9 system for efficient in vivo gene editing in the brain. In this study, I will discuss the recent updates on the in vivo therapeutic editing using CRISPR/Cas9 as a novel therapeutic agent for Alzheimer’s disease (Nature Neuroscience 2019).