Multiple studies have claimed that microglia and oligodendrocytes play an important role in the development of Alzheimer's disease (AD), but using genetic techniques such as gene editing these two types of cells in vivo is challenging as there are no efficient and specific vector tools to deliver genes to these cells. So we proposed some methods to achieve this goal. By combining viral libraries with evolutionary screening, we will screen vector tools that can specifically and efficiently infect this type of cells. First, these tools will make it easier for scientists to precisely manipulate cells to explore the role of these cells in the occurrence of various brain diseases; secondly, these highly specific tools can be used to precisely edit a certain type of cells, so that other cell types are affected minimally. When AD occurs in early stages, APOE4 should be precisely edited into APOE3 in microglia or oligodendrocytes to see if the progression of AD is improved.