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Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/62137

#### **Abstract**

Gene-targeting strategies based on nucleic acid have opened a new era with the develop‐ ment of potent and effective gene intervention strategies, such as DNAzymes, ribozymes, small interfering RNAs (siRNAs), antisense oligonucleotides (ASOs), aptamers, decoys, etc. These technologies have been examined in the setting of clinical trials, and several have recently made the successful transition from basic research to clinical trials. This chapter discusses progress made in these technologies, mainly focusing on Dzs and siR‐ NAs, because these are poised to play an integral role in antigene therapies in the future.

**Keywords:** Gene-targeting strategies, DNAzymes, siRNAs, basic research, clinical trials
