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Ethical implications of gene testing

What exactly do we know from the Human Genome Project? Up until now, the project has resulted in sequencing the DNA of a majority of the human genetic code. While the DNA sequence may have the capacity to tell us all the physical and possibly even behavioral characteristics of a person, we are not yet able to glean this information from a person's DNA. In other words, the human genetic code has not been cracked completely. Currently, we know the function of only a small percentage of the estimated 30,000 genes in the human genome. Before we try to discover the function of every gene, we need to prepare for the implications that will result, especially regarding gene testing in the medical field.

Disorders such as cystic fibrosis, Duchenne muscular dystrophy, or Huntington's disease are a result of genetic defects. Scientists have found the mutated genes that cause these diseases and others. A genetic disorder can be found by looking at a person's DNA at the molecular level. This is known as gene testing. Currently, there is a fairly short list of hereditary genetic diseases that have an associated gene test, but the list has the potential to become very long.

Gene testing can be used in many different situations. For example, each individual has two copies of each gene, one from the mother and one from the father. In some cases, a person needs two "bad" copies of a gene to have the disease, while a person with only one "bad" copy, a carrier, does not have the disease. When two people decide to have a child, their DNA can be tested to determine if they are carriers. The results can predict if their future child has a chance of getting two "bad" copies of a gene, causing a genetic disease. A child can also be tested for genetic diseases right after birth. Another possible application is the screening of in vitro embryos for genetic diseases before they are implanted. Both adults and children can be tested to see if they will develop late-onset genetic diseases. A person can also be tested to estimate the risk of developing disorders such as cancer and Alzheimer's disease. A doctor can use gene testing to diagnose or rule out the cause of a patient's symptoms.

On the surface, gene tests seem to be amazingly useful. Gene testing can inform potential parents of the risk of having a child with a genetic disease. Also, knowing which defective genes a person has, whether adult or child, can be very beneficial. Perhaps a change in lifestyle or treatment with a drug can stop the disease before it starts. Gene tests enable doctors to be sure of a diagnosis, allowing them to prescribe the exact treatment necessary for the patient. Perhaps someday drugs will be tailor-made for a specific genetic defect.

Even with all of these benefits, there are many ethical issues that need to be examined. First of all, how do scientists determine the accuracy of the tests? There could be more than one genetic defect and/or environmental factors that cause a particular disease, making it difficult to determine risk with a gene test. Therefore, how should gene tests be regulated to be sure that they give factual results?

Also, should there be regulation on the types of genetic defects that are tested? For example, some forms of poor eyesight as well as a person's chances for becoming bald are genetically determined. Scientists could develop gene tests for these traits. These tests could then be used on in vitro embryos that are screened before implantation. Will gene tests such as these be used to create the "perfect" child, or will their only function be to test for genetic defects that cause untreatable diseases?

How does society decide whether or not a genetic defect is a disorder that should be tested for and treated? Currently, gene tests are very expensive and, therefore, not available for all people. As a result, gene testing could create a larger division in our society. The separation between the rich and the poor could become even greater as a result of gene testing. People with genetic disorders could be seen as even more of an outcast than they are today. Also, who should have access to the results of gene tests? If insurance companies or employers gain access to the results, then they could discriminate based on a person's genetic code.

Imagine for a moment that a healthy, young man is at the doctor's office for his yearly physical. As a result of a gene test, the doctor discovers that he will eventually develop a fatal disease for which there is no current treatment available. Should the doctor tell the patient about his condition? Should there even be a gene test for fatal diseases for which there is no current treatment or cure?

Along with the problems of gene testing comes a deeper issue: what it means to be human. With the hype surrounding the Human Genome Project, it seems as though the general population is falling towards a completely genetic view of what it means to be human. They believe than genes control a person's physical and maybe even behavioral characteristics. Will there come a time when a person is identified by his genetic code? Will gene testing bring us to a scientific way of judging a person's worth in society? How much do our genes, our experiences, and our environment play a role in our humanness? Finally, how does all of this information come together to define what it means to be human?

[ Posted by Natalie Weaver at June 1, 2001 09:42 AM | More Opinion articles ]

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