Genetic Engineering

Developments in modern genetics also have pre­sented us with new ethical problems. The Human Genome Project, an effort to map the entire human genome, was completed in the summer of 2000 and

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its results first published in early 2001. The map was expected to contain 100,000 genes, but scien­tists now believe that only 20,000 human genes exist. Humans have roughly the same number of genes as other animals, but scientists found that "we have only 300 unique genes in the human (genome) that are not in the mouse," for example.²⁶ However, although humans have approximately the same number of genes as a spotted green puffer fish, it is surmised that human capacity comes from "a small set of regulatory genes that control the activity of all the other genes." These would be dif­ferent in the puffer fish.²⁷

Two entities had competed in this race to map the entire human genome. One was a public con­sortium of university centers in the United States, Great Britain, and Japan. It made its findings pub­licly available. It used the genome from a mosaic of different individuals. The other research was done by Celera Genomics, a private company run by Dr. Craig Venter. It used a "shotgun" strategy. Its genetic source material came from Venter and four others. Celera also proposed to make its results available to the public after they have been ana­lyzed—that is, to tell where the genes lay in the entire DNA sequence. Later the company expects to charge a fee to use its analyzed database. On September 4, 2007, Dr. Venter published his entire genetic sequence.²⁸

The next efforts have been to determine what role the various elements, including the genes, play. In this effort, one focus has been on individual dif­ferences. The human genome, "a string of 3 billion chemical letters that spell out every inherited trait," is almost identical in all humans: 99.99 percent. But some differences, so-called genetic misspellings that are referred to as single nucleotide polymor­phisms (SNPs or "snips"), can be used to identify genetic diseases. The SNPs give base variations that contribute to individual differences in appear­ance and health, among other things. Scientists will look for differences, for example, by taking DNA samples of 500 people with diabetes and a similar number from people without the disease and then look for DNA patterns.²⁹ The SNPs also influence how people react differently to medications. Some people can eat high-calorie and high-fat foods and

still not put on weight while others are just the opposite. Some have high risks of heart disease, whereas others do not. With genetic discoveries based on the Human Genome Project and more recent efforts, one hope is that diets will be able to be tailored to individual human genetic makeups. This opens new fields of personalized medicine and nutrition known as pharmacogenomics and nutrige nomics.-*⁰ However, these fields are in their infancy and the science behind them is just emerging, so people are cautioned not to expect that they can plunk down $200 for an individual scan that will detail their personal genetics.

Still, much work is now being done in this area. For example, on October 30, 2002, "a $100 million project to develop a new kind of map of the human genome was announced." The group behind the effort is an international consortium of government representatives from Japan, China, and Canada, and the Wellcome Trust of London. The U.S. NIH is investing $39 million in the project. The "goal is to hasten discovery of the variant genes thought to underlie common human diseases like diabetes, asthma and cancer."³¹ Scientists will use the Human Genome Project map as a master reference and compare individual genomes to it. They then expect to locate the genes that cause various dis­eases. Some diseases are caused by single genes, such as that producing cystic fibrosis, but others are thought to be caused by several genes acting together. Other genes might be discovered that relate to certain beneficial human traits. For exam­ple, some scientists are working on locating what they call a "skinny gene." Using mice from whom a single gene has been removed, scientists at Deltagen, a company in Redwood City, California, have been able to produce mice that remained slim no matter how much they were fed.³² According to geneticist David Botstein, the impact of the Human Genome Project on medicine "should exceed that 100 years ago of X-rays, which gave doctors their first view inside the intact, living body."³³ Currently, "gene therapies are being developed that would block myostatin in humans," something directed to the treatment of muscular dystrophy and frailty in older persons. Myostatin curbs the growth of mus­cles. However, this also has wider applications. For

Chapter 17 ■ Stem Cell Research, Cloning, and Genetic Engineering 415

example, a breed of cattle called Belgian Blue has been developed that has huge muscles and very little fat.³⁴ This may also cause concern about its use by athletes, who could pump up without much effort. Moreover, "gene therapy leaves no trace in the blood or urine," which would make drug testing of athletes, which is already problematic, even more difficult. Other gene therapies, including so-called gene doping, have been and are being devel­oped that could cause the human body to produce more red blood cells. Persons with this natural abnormality have been exceptional athletes, including a gold medalist in cross-country skiing.³⁵

Etbical Issues

Before new developments in genetics can be trans­formed into practical benefits, studies using human subjects often must be done. Since the Nuremberg trials and the resulting code for ethical experimen­tation, informed consent has been a requirement for the conduct of research that involves human subjects. Consider a study designed to determine the possible benefits of an experimental treatment for Parkinson's disease.³⁶ This frightening disease afflicts 1.5 million people in the United States as well as many others around the world. Its sufferers first experience weakness and then slurred speech, uncontrollable tremors, and eventually death. The cause of the disease is not entirely known and there is no cure yet. What is known is that the disease works by destroying a small section of the brain, the substantia nigra, which controls movement. One new hope for treatment of Parkinson's disease uses the transplanted brain cells from aborted six-to eight-week-old fetuses.³⁷ Are the patients in this trial and others that involve genetic engineering likely to be able to give the requisite kind of informed consent to guarantee that the experiment is ethically acceptable? Consider the actual case. The potential participants already have experi­enced some symptoms of the disease. Here is a treatment that promises to help them. They are informed that the study is a randomized clinical trial and that if they agree to participate they may or may not get the experimental treatment. If they are randomized to the control group rather than the treatment group, then they will go through the same

procedure including having holes drilled in their skull and tubes passed into their brain, but they will not actually be receiving anything that will benefit them. In fact, like those in the treatment group, they will be subject to the usual risk of brain damage and stroke that accompanies the procedure.

What kind of thought procedure would such persons be likely to undergo in the process of deciding whether to participate in this trial? Is informed and free consent likely? Would they really be informed of the various details of the proce­dure? Would they really understand their chances of being in the treatment group? Would they be influenced, if not coerced, into joining the study because of the nature of their disease and great need? Would they also have to be willing to undergo this risky procedure solely for the sake of the knowledge that might be gained from the study and not for their own immediate benefit? In other words, would they have to be willing to be used as guinea pigs? It is possible that the conditions of genuine informed and free consent would be met. However, it is also likely that these conditions could not be met, because the patients either would not understand what was involved or would be coerced into participation.

As in the testing of many new medical thera­pies, modern scientific methodology demands that studies be controlled and randomized; otherwise, the information derived could be unreliable. However, to do this particular study we seem required to violate one demand for an ethical experiment that uses human subjects—namely, that the participants' consent be informed and uncoerced. What we have here is an example of one of the many ethical dilemmas that we face today because we live in a world in which modern science and technology are pervasive. We use knowledge gained by science to help us, but we are also subject to the demands of science. Modern technologies provide us with many goods and opportunities, yet in giving us more choices they also present us with more difficult ethical deci­sions. The decisions have no easy answers. Another ethical question that scientists sometimes face is whether one should let ethical concerns determine whether to carry on some research. One

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example of this was the Tuskegee syphilis study in Chapter 5 when we introduced Kant's moral theory. Is knowing always a good and thus should the sci­ence that helps us know what is the case always be pursued? Those who analyze the ethics of research using human subjects continue to debate the issues surrounding the informed consent require­ment. In the end, this requires that people not be used or that they not be used for goals and pur­poses to which they do not consent or make their own. You may recognize this as a requirement of Kant's moral philosophy and can refer to the dis­cussion of its basis in Chapter 5. In this chapter, we will suggest ways to analyze a few other prob­lems that modern science and technology now present us.

The possibility of gene therapy also presents us with new ethical problems. If it were possible to use these methods to activate, replace, or change malfunctioning genes, then this would be of great benefit for the many people who suffer from genetic diseases. Using genetic techniques to provide human blood-clotting factor for hemophiliacs, man­ufactured human insulin for diabetics, human growth hormone for those who need it, and better pain relievers for everyone is surely desirable and ethically defensible. However, use of the technology also raises ethical concerns. Among these questions are those related to the risks that exist for those who undergo experimental genetic therapies. We also should be concerned about the access to these pro­cedures, so that it is not just those who are already well off who benefit from them. The biotechnology industry continues to grow. Should information and products of great medical benefit be able to be kept secret and patented by their developers? For example, the company Myriad Genetics recently announced that it had found a gene linked with breast cancer. The company also has attempted to patent the gene.³⁸ In another example, a newly developed technique allows the alteration of genes in sperm that would affect not the individual him­self but his offspring and thus alter human lin­eage.³⁹ It is one thing to do this in the interest of preventing genetic disease in one's offspring, but it is quite another to add new genetically based capa­bilities to one's children or to the human race.

Although these are still somewhat remote possi­bilities, they give us cause for some concern, not the least of which is whether we are wise enough to do more good than harm by these methods. Two of the National Bioethics Advisory Commission's major topics of discussion are the rights of human research subjects and the use of genetic informa­tion. You can continue to follow news accounts of the new reproductive and genetic technologies as well as the reports of committees such as the President's Council on Bioethics. As you do, you should be more aware of the variety of ethical issues that they involve or address. The issues are complex, but the first step in responding to them is to recognize them.

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