After the sequencing of the whole human genome, gene therapy has been a hot topic. Theoretically gene therapy will be the ultimate treatment for human genetic diseases, and can be the same powerful in modifying non-genetic diseases. The first few attempts in human gene therapy were not without trouble. However, there are a lot of developments in gene therapy in these few years, and successful examples in both the treatment of animal models and clinical trials are plenty.

　　In the field of viral vector related gene therapy, the developments of new vectors are the most important progresses. Adenovirus associated virus (AAV) vector is safe and convenient. In many mouse models of genetic diseases, a single injection of viral vector essentially cures the disease. Human clinical trials are also successful in a number of eye, liver and central nervous system diseases. Lentivirus vector has also replaced retrovirus vector in gene therapy for hematological diseases for its better safety profiles.

　　Non-viral method in gene therapy also has many exciting progresses. RNA or oligonucleotide therapy is safe, easy and efficient. These small molecules can alter normal or pathological mRNA splicing, or suppress gene expression. Clinical trials in both Duchenne muscular dystrophy and spinal muscular atrophy both show encouraging results. More recently, the techniques in gene editing advance a lot. Hopefully gene therapy can easy repair human genes, treat more human diseases, and improve human health in the near future.