There is a number of diseases that can’t be treated with specific drugs or antibiotics because of their genetic nature. Genetic disorders involve a wide range of disasters caused by the improper functioning of a single gene or several genes. Drugs and antibiotics used by the classical medicine can just facilitate the state of the patient, they can’t cure him. The only field of medicine that can deal with genetic disorders when they have already developed in a person is gene therapy (Touchefeu Y. et al., 2010).
Gene therapy is usually used to deal with monogenic disorders, like cystic fibrosis, polydactyly, sickle cell anaemia, thalassaemia and others. In the classical approach gene therapy involves the isolation of a normal target gene, its insertion into a virus vector with reduced pathogenic abilities and delivery of the gene into target host cells by the virus. In the case of cystic fibrosis, for example, an adenovirus delivery system is used (Xiao P.J. et al., 2012). Besides adenoviruses, retroviruses, adeno -associated viruses and herpes simplex viruses can be used for gene delivery. But there are some ethical and moral issues coming from using viruses as delivery systems. That’s why new methods to bring the DNA into the cell were developed. Liposomes are small lipid granules carrying the target genes. They don’t cause immune reactions and considered to be a better delivery system than a virus (Patil P.M. et al., 2012).
The ways described are used when the disease is a recessive disorder. But if it is a dominant disorder, gene therapy uses methods of RNA silencing to inactivate the genes involved into the disease development. Specific synthetic RNA molecules can be delivered into the cell, via the methods discussed, to disrupt the expression of the disrupted gene. Besides of monogenic disorders curing gene therapy has been shown to have a significant effect on the polygenic disorders curing, like Parkinson’s and Alzheimer’s diseases (Patil P.M. et al., 2012).
From one point of view gene therapy is advantageous as it allows people to get rid of the disorders incurable by usual medicine. But from the other side, it requires high accuracy and precision. It also causes some ethical problems as involves human genome manipulating as well as it may cause hard complications if something goes wrong.
References
Touchefeu Y., Harrington K.J., Galmiche J.P., Vassaux G. Review article: gene therapy, recent developments and future prospects in gastrointestinal oncology. Alimentary pharmacology and therapeutics. 2010. 32(8): 953-968.
Xiao P.J., Lentz T.B. and Samulski R.J. Recombinant adeno-associated virus: clinical application and development as a gene-therapy vector. Therapeutic delivery. 2012. 3(7): 835-856.
Patil P.M. Chaudhari P.D. Megha S. and Duragkar J. Review article on gene therapy. International Journal of Genetics. 2012. 4 …