Melanie Unruh, R.N., B.S.N.
Intern, The Tennessee Center for Bioethics and Culture
November 2007
I admit it. I am a science fiction freak. Although I have never been a reader of comic books, recent movies such as “Spiderman” and “The Fantastic Four,” and the ideas behind the popular television series “Heroes” fascinate me. As schools have taught that man is the product of genetic evolution, movies and television shows capitalize on this culture, encouraging the idea that we will soon be able to control our own evolution. Most commonly, cultural genetics portrays random mutations or engineered genes as the source of superhuman abilities. But is the genetic manipulation and enhancement of mankind future fact or fiction?
To achieve human enhancement through genetic engineering, what would be required? We would need to have comprehensive knowledge of the human genome and its functioning. We would also need to have an efficient and safe way of altering the human genome.
The completion of the initial sequencing of the human genome was announced in 2000 by the Human Genome Project and by Celera Genomics Corporation. At that time it seemed our genetic futures lay within our grasp, but genetic information has since proven to be more complex. Researchers have found that individual genes can contribute to more than one trait. Recent research shows that sections of DNA previously thought to be simply “filler” or “junk” DNA may actually serve as complex regulatory elements in gene expression and protein production.
Dr. Francis Collins, director of the Human Genome Project, admits that this new information will require the scientific community “…to rethink some long-held views about what genes are and what they do, as well as how the genome’s functional elements have evolved.” Yet even if we do achieve comprehensive knowledge of the human genome, would that give us the power to enhance humankind?
In addition to comprehensive knowledge of the human genome, we would need an efficient and safe way of changing individual genes or delivering new genes. There are two general ways this could be done: genetic therapy, and germline engineering. The goal of genetic therapy is to deliver a correctly “spelled” gene to an individual’s cells, usually using modified viruses as the carriers. Clinical trials for gene therapy have been underway since 1990. Success was seen in 2002 in the treatment of severe combined immunodeficiency disease, but the treatment later activated a cancer-causing gene. Because of these results, the FDA temporarily halted genetic therapy trials.
More recently the July, 2007 death of Jolee Mohr, who was participating in a phase I/II study of recombinant genetic therapy for inflammatory arthritis by Targeted Genetics Corporation, has raised concerns again about the safety of gene therapy. Even if gene therapy some day proves to be safe, it generally only affects certain tissues, and the likelihood of its becoming a permanent solution for genetic diseases seems distant at best.
To alter permanently the genetic structure of every cell in a human body, the most likely method would be germline engineering. This technique alters the genetic structure of germline cells (egg, sperm) or of an embryo. To effect one genetic change in a single human embryo would be an extremely complicated process. Dr. Jon W. Gordon, researcher and author of The Science and Ethics of Engineering the Human Germ Line: Mendel’s Maze, examines this question. To gain one genetically altered cell would require thousands of stem cells to manipulate. These would necessitate, by Dr. Gordon’s estimate, at least 250 embryos created for this purpose. After manipulation and identification, statistically one stem cell will have incorporated the new gene. The nucleus of this cell would then be inserted into an emptied egg and stimulated to grow into an embryo, creating a cloned embryo with the new genetic structure. After this lengthy process, there is no guarantee that the embryo would develop correctly, or that some other genetic mutation might not occur as a result of both the gene delivery and cloning process.
So will the future see enhanced humans with the abilities of Spiderman or the villainy of Syler? Will the genetic manipulation and enhancement of humankind be more than television fiction? Most likely not. While scientific advances may surprise us, the monumental obstacles genetic engineering faces in safety and efficacy alone preclude the mass engineering of the human race. Even so, will we attempt it? And what risks are we willing to take? As research in stem cells, cloning, and genetics continues, what safeguards will we put in place to protect people? The desire to create the superhuman has been seen in our recent history. How far will we allow our dreams and desires for a disease-free and empowered human race to lead us? And who will pay the price along the way?