Gene Therapy

There are numerous uses for biotechnology, and the implementation of biotech solutions is becoming increasingly popular as more advances occur within the field. No-one quite knows where the technology may lead, and could possibly one day be found to be implemented in the production of products as diverse as puppy food to the creation of more sustainable buildings.

As mentioned elsewhere on this site, one of the most exciting developments for biotech has been in the domain of medical science: our increasing knowledge of the molecular processes in cells has multiple implications for the treatments of disease and illness.

A relatively new method of treatment made possible through the use of natural processes as a technology/tool is gene therapy. Although still in its infancy (and in many ways its experimental stage) gene therapy might well prove a miracle cure for a vast range of diseases in the future.

Gene therapy is earmarked as a highly plausible future means of treatment, or even cure, of a variety of genetic and acquired diseases. Notably, this list includes cancer and AIDS. In gene therapy, normal genes are inserted into pathological cells to either replace or bolster the cell’s normal functioning. The cells that gene therapy methods can target are somatic cells and gamete cells. The difference in effect between the two cell types is basically that the modification made to the genetic code of the somatic cell is not passed on to its daughter cell when it divides, but in the gamete cell the modification is passed on in cell division. The intervention in sperm and egg cells (gametes) is therefore for the purposes of generational change. Theoretically, one well designed intervention could remove a genetic defect from a family tree for all future generations: the gene therapy would therefore only have to be applied to one generation of gamete cells.

Gene therapy can be enacted either while cells are in the patient’s body or the cells can be removed and the process implemented within a laboratory: the former is known as In Vivo treatment and the latter as Ex Vivo treatment.

  • In Vivo: in this form of treatment, “vectors” (usually a virus that has been neutralised and now carries the desired gene) are injected into the patient’s bloodstream. The vectors, following the normal behaviour of virus, enter into the cell and insert their genetic material into the nucleus. As the virus is no longer a threat and instead carries a gene to cure the malfunctioning cell, the effect of the virus is beneficial.
  • Ex Vivo: in this form of therapy, cells are removed from the patient’s blood or bone marrow and grown in a laboratory. Vectors are again used to deliver a specific gene into the cells, and these modified cells (that is, with a slightly altered DNA) are then reinserted into the patient’s body.

Unfortunately, gene therapy has many challenges to overcome before it can be used on a widespread and large scale. Four central issues have been identified as follows:

  • Gene Delivery Tools: the viruses used for the delivery of a gene to the target cell, despite having their own harmful genes removed, can nonetheless still cause immune responses, inflammation and toxicity. Whereas these side-effects might be worth the while in some instances, in other situations they could be serious and highly counter-productive.
  • High Costs: as with most new techniques, the costs involved in the initial phases are prohibitively high. At this point in time, only developed countries are enjoying the benefits of gene therapy.
  • Limited Knowledge: our understanding of genes is still very limited. Whereas enormous strides have already been made, scientists have to build databases of the exact roles identified genes play in cell functioning. Considering the complexity of DNA, this process might still take many years.
  • Complexity of Disorder: many diseases involve multiple genes, and more must be understood about how genes interact before implementable treatments can be put in place. Moreover, the role of lifestyle and environmental effects, and how they influence cell functioning, is similarly an area in which research must still be done.