**2.2 Antisense and RNAi technologies**

Many tools have been involved in target validation since the 1980s. Target identification and validation are long procedures. They were mainly based on structureactivity relationship. The drug discovery system becomes the most important approach towards the targeted cells [11]. Traditional antisense and RNA interference (RNAi) technologies are the robust tools used in multidimensional phases to discover and validate the potential drug targets. This approach elaborates the potentially selective cleavage of a targeted messenger RNA. This targeting technique enables the researchers to explore the protein-based expression on phenotypes [12].
