Genetic engineering: applications and implications

Biology - Genetic Engineering

GENETIC ENGINEERING: APPLICATIONS and CONTROVERSIES

Genetic engineering is the process of deliberately changing the genetic material of an organism by manipulating its deoxyribonucleic acid (DNA) molecular structure for the purpose of transmitting those specifically designed changes to successive generations via genetic inheritance. The first documented (albeit unintentional) experimental demonstration of genetic engineering actually preceded the identification of the DNA molecule by almost thirty years (Aldridge 1998).

British microbiologist Fred Griffith identified two forms of the pneumococcus bacterium distinguishable by the presence or absence of a smooth exterior cellular coating responsible for its resistance to the human immune system response. Griffith accidentally transmitted that characteristics of the deadly pneumococci responsible for human pneumonia to subsequent generations of the harmless pneumococci that lacked that distinctive exterior coating (Aldridge 1998).

The subsequent discovery of the underlying structure of the DNA molecule and specific mechanism of genetic inheritance announced by James Watson and Francis Crick in 1957 lead to the eventual explosion of DNA sciences including the purposeful alteration of genetic material to produce desirable genetic traits in biological organisms.

In fact, so much research into the mechanics of human heredity were conducted in the interim between Griffith's first experiments that culmination in their 1957 announcement for which they shared a Nobel Prize, that the work of Watson and Crick is considered by many to unfairly overshadow the valuable contributions of Griffith and other predecessors (Gibbon 2002).

Since then, genetic engineering techniques have been widely used for different beneficial applications: in agriculture, modern farming incorporates genetic engineering to produce higher quality crops and healthier cattle; and in industrial applications, genetically modified bacteria have been developed into organisms capable of absorbing toxic wastes and oil spills (Elias 2006).

Some of the most dramatic and potentially useful applications of genetic engineering technology relate to medical science and human heath, representing practically unlimited potential for treating and even eliminating many forms of human disease entirely. However, because it involves the very mechanism of inheritable human characteristics, genetic engineering has also generated intense political debate and opposition, primarily from religious groups who view it as interfering with "God's work" (Sagan 1997). In that regard, the most controversial form of genetic engineering relates to human cloning, mainly because the general public is largely ignorant of the fundamental difference between the myriad beneficial applications cloning technology and the actual use of those techniques to clone an actual human being (Saunders 2001).

Beneficial Applications: Mankind has been purposely changing the characteristics of crops and livestock from the earliest recorded history, and long before any scientific understanding of heredity. Mere observation and simple deduction prompted the selective breeding of practically everything cultivated for human consumption. In principle, genetic engineering accomplishes the same purpose, except directly rather than indirectly.

Whereas selective breeding involves controlling the reproductive opportunities of biological organisms, genetic engineering allows scientists to add (or remove) specific genetic material to the living cell at the microscopic level of the genome to produce desired changes in the characteristics of successive generations. Modern applications of genetic engineering principles have made possible the manufacturing of artificial insulin used to treat diabetics as well as the process of in-vitro fertilization (IVF) used to assist infertile couples conceive, often using their own genes.

One of the applications of genetic engineering with the most beneficial potential relates to the isolation of human stem cells for the treatment of disease. Embryonic stem cells, in particular, represent the greatest beneficial applications, because they are capable of being extracted from the same embryos already made available through the IVF process and then used to develop virtually any type of human tissue required (Pollack 2007).

The use of stem cell technology will eventually make organ (and bone marrow) donation unnecessary, because genetically engineered replacement organs will be able to be developed using the patient's own tissues. In addition to eliminating the need for powerful anti-rejection drugs currently required to prevent organ recipients from rejecting their transplants, the incorporation of genetically engineered replacement organs will provide life-saving organs for the many thousands of patients who die every year while waiting for one of the few compatible organs that become available (Zuckerman 2005).

Because genetic engineering alters the molecular structure of the cells responsible for human heredity, its applications include the elimination of all human hereditary disease, including diabetes, cystic fibrosis, Parkinson's, Sickle Cell Anemia, Tay-Sachs, Alzheimer's, and many forms of cancers. Likewise, aspects of genetic engineering and stem cell technology offer long-term hope for victims of traumatic paralysis through the use of to repair spinal cord damage by providing artificially engineered nerve growth.

Ethical Controversies:

Precisely because genetic engineering allows scientists to manipulate the very essence of what makes us who we are, the field has generated significant opposition.

Religious beliefs about the sanctity and "special" character of human life inspired intense political opposition to the wider incorporation of genetic engineering science necessary to reap its full benefit by successfully promoting and lobbying for bans on federal funding on some of the most beneficial applications of genetic engineering (Pollack 2007).

Secular medical ethicists have also raised concerns based on the potential use of genetic engineering for full-scale human cloning. In principle, the same technologies that enable the development of autogenic human tissues and organs are also capable of producing human beings without the necessity of combining the DNA of two parents. In the same way that scientists have already managed to clone sheep and other animals (Saunders 2001), they could also do the same using the genetic material of a single adult individual to produce an identical clone of that person.

In fact, the established medical community has no such plans, because they recognize both the ethical implications of non-medical uses of genetic engineering technology as well as the many formidable technical obstacles already encountered just in animal experimentation (Saunders 2001).

Conclusion:

The purposeful manipulation of genetics is a practice that substantially predates modern medicine, and in all likelihood, all of recorded human history. Advances in medical science in the 20th century have allowed scientists to achieve the same end directly, by altering genetic heredity at the molecular level that used to be implemented indirectly through selective breeding.

Already, the evidence suggests that the continued development of genetic engineering science has the powerful potential to revolutionize medical science, primarily by eliminating inheritable disease at the genetic level rather than merely treating it once it manifests itself in symptoms and disabilities. At the same time, antiquated traditional religious beliefs have generated significant opposition to some of the most valuable potential uses of genetic engineering science.