The Pros And Cons Of Gene Therapy

Gene Therapy is an experimental technique that involves altering genes inside the body in order to treat or prevent disease. Since the understanding of the flow of genetic materials in organisms is established, the cause of disease has been linked to the abnormal expression of genetic information. It is believed that diseases are treatable by correcting such defects; hence gene therapy evolves as an active field of research. The first clinical trial of gene therapy was started at NIH Clinical Center in 1990 (National Institute of Health, 2005-2014). However, it is not until 2012 that Glybera appeared as the first gene therapy to be approved in European Union (EU). In this essay, several technical challenges in the successful development of

Factors such as vascular supply, endothelial barriers to organs, vector size and interaction between vector ligand and host cell receptors would need to be taken into careful consideration (Kay, 2011). Viral vectors are mostly used due to the capacity of viruses to integrate DNA fragment and their intrinsic ability to enter the cell (Bessis et al., 2005). The presence of natural ligand on the virus surface aids the uptake of viral vectors by the host cells. The vectors will be enclosed in endosomes and need to be released to enable the effect of the therapeutic gene; virus has evolved to have mechanism to escape from the

Retroviruses are very important in current gene therapy approaches; they contain a reverse transcriptase which allows for the integration into the host genome. Retroviruses have been used in a number of FDA approved clinical trials such as the X- linked Severe Combined Immunodeficiency (SCID-X1) trial. Lentiviruses, a subclass of Retroviruses, have been recently adapted as vectors due to their ability to integrate into the genome of non-dividing cells. Adenovirus is a class of virus with double stranded DNA genome that can cause respiratory, intestinal and eye infection (especially the common cold). In comparison to lentiviruses, adenoviruses do not integrate into the genome and they also do not replicate during cell division. Adeno-associated viruses (AAV) are small viruses that infect humans and some primate species. It can infect both dividing and non-dividing cells and may incorporate its genome into that cell. (News Medical,