Chapter 12 : Genetics, Intervention, Control, and Research
|Section 2. Social Context
This section was organized, prepared and written by Mark Riddagh (SCCC, 2006) using Ronald Munson's Intervention and Reflection as a guide.
In 1953, James Watson and Francis Crick produced a model that mapped the structure of a stand of DNA. In 1988, some 35 years later James Watson was asked to direct the most ambitious genetic project of all time, the Human Genome Project. The HGP promised to map the complete sequencing of the human genome and with that knowledge secure the ability to control genes and the way they affect human beings.
Considering the forty-six human chromosomes, each of which contain between 50,000 and 100,000 genes that could form up to 3 billion base pairs, the project promised to be on a scale larger than anything ever attempted. Many researchers believed that such efforts, and financing, could be more effectively applied to smaller project of greater immediate benefit. Consequently, in 1985, when biologist Robert Sinsheimer first proposed the project, it received a lukewarm reception. The general attitude changed however, with the advent of two unparalleled events. First, the National Research Council supported the project and second, James Watson agreed to be the project’s director. By 1988, most critics had adopted a new enthusiasm and despite the overwhelming size of the project, researchers saw the dawn of a new future for genetic research. Indeed, most researchers came to believe the HGP to be invaluable for future research.
The National Research Council initially outlined a path for the participating research to follow. It was expect to cost between 3 billion and 5 billion dollars and completion was projected to take from fifteen to twenty years. The success of the project, however, brought about distinct modifications in the original plan. Although Congress initially budgeted 31 million to get the ball rolling, the project eventually commanded and annual expense of $200 million. Likewise, the original year of completion was projected for 2005, but that date was subsequently re-evaluated to be closer to 2003. Nevertheless, in 1999, when the project began, the head of the Celera Corporation claimed the sequencing would be completed by 2001.
The information the project has uncovered has truly provided substantial benefits. The most significant of these has been an understanding of the way specific genes are related to certain diseases. Additionally, the speed at which these relationships have been identified has been astounding to say the least. Of a list of 1000, a small sample can illustrate the success the HGP has encountered:
• Colon Cancer – the marker was found on chromosome 2 as a mutation of a gene that repairs errors in DNA. When mutated, the gene triggers multiple mutations to other genes. While one in two-hundred people have the gene, sixty-five percent of them are likely develop the cancer.
• Amyotrophic Lateral Sclerosis (Lou Gehrigs Disease) – caused by a mutation of a gene on the 21st chromosome, which produces an enzyme that works to eliminate free radicals. If uncontrolled, it can cause nerve damage affecting motor reflexes and eventually lead to muscular deterioration.
• Type II Diabetes (adult onset) – a gene on chromosome 7 codes for the production of an enzyme related to insulin production. When mutated forms of the enzyme are produced, then failure of insulin production results.
• Alzheimer’s Disease – a gene on chromosome 19 codes for a protein involved in cholesterol transportation. The risk of the disease increases by eight times in people who have both alleles of the protein.
These are only a few of many diseases found to be linked to genetic triggers and additional research promises to provide even more of the markers for many other diseases currently suffered by human beings. Furthermore, the discovery of genes that predispose one to specific diseases has spawned the development of tests that effectively screen for these genes.
Germline therapy, which is like gene therapy except the modification takes place in the sex cells. It is what we think of when we think of genetically engineered people. It is around germ line therapy that many of the moral dilemmas related to genetic screening really result and it is still far in the future.
Since the Human Genome Project has so successfully identified a multitude of genes and gene markers, tests for genetic screening have become more common in the industry. These tests are becoming cheaper as biotechnology becomes more advanced and the utilization of such tests will increase as a result. Unfortunately, the advancement of genetic research has shown that although understanding is increasing, genetic disease is more complex than may have been anticipated. Although someone may carry a gene related to a specific disease, it is rare that the disease will manifest based solely upon the fact the he or she is a carrier. Even though single-gene disorders, like Huntington’s disease and sickle cell have been studied by genetic researchers, they account for only 2% of all genetic disorders. Most disorders result from genes that may have thousands of mutated forms. Additionally, the presences of other genes as well as environmental conditions also factor into the likelihood that genetic disorders will develop.
The ability to screen for genetic disorders has uncovered a common desire to avoid any knowledge of their genetic makeup; it appears that nearly 50 percent of the population would rather remain unaware of their potential for developing a disorder. Surveys show half of those questioned said that they would not want to know if they are prone to develop a specific diseases/disorder later in life. Still, the other half of the population would welcome the opportunity to prepare for future medical treatments if not a chance to bypassing a disorder altogether. Those who find comfort in not knowing may well be rejecting the benefits that genetic screening promises. With early detection of one’s vulnerability to a specific disorder, one could well avoid the environmental factors that act as a trigger. This is only true for some disorders however whereas others, like Huntingon’s disease, early detection offers no effective treatment or provides any benefit to the victim. In other cases, if the gene for xeroderma pigmentosum is found, with proper avoidance of sunlight, one may prevent the onset of melanoma. Moreover, conditions like breast cancer offer only ambivalence associated with a pre-knowledge. Woman who carry the mutated gene responsible, making them 85 percent more likely to develop breast or ovarian cancer by age 65, have no guarantee that diet, exercise and alcohol consumption are linked to onset. Further, a gene carrier may opt for a prophylactic double mastectomy; unfortunately, the cancer may still develop in the surrounding tissue. Currently, there is no support weighing the scale in either direction, which may account for the near 50/50 split in opinion about genetic test screening.
Despite the split opinion concerning the pros and cons of knowing one’s susceptibility to disease, another worry has arisen. Critics of human genome knowledge claim that this understanding opens the door for discrimination. Whether one is aware of their genetic condition or not, surveys show that the majority of people are united in not wanting their employers to know. When asked, "Do you think it should be legal for employers to use genetic tests in deciding whom to hire?" (Munson – 563) 87 percent were opposed to the idea.
Employers on the other hand, may feel compelled to use such knowledge as a means of protecting and proving the safest atmosphere for their employees. An example of such an argument might be, since some people are vulnerable to a form of anemia, which is trigger by naphthalene, then those who carry the gene should not be hired into positions that require prolonged exposure to the chemical. In essence, those with specific vulnerabilities to certain environmental factors should not be endangered in a job that compromises their well-being. Employers could use genetic test screening to place there employees in positions that are best suited to their genetic makeup and thereby protecting them from the factors that could cause the manifestation of such disorders. For those who would rather not know their results, the employers can arrange employees as necessary without including them in the reasoning for their specific job placement.
Labor unions, civil /women’s rights groups and other activists quickly refuted these arguments, because the potential for discrimination could not be effectively controlled. An example for the opposition might be, since African Americans are more susceptible to environmentally triggered anemia, they would be ineligible for jobs that propose a greater risk to them than workers of other nationalities. Because of similar concerns, the Equal Opportunity Commission interprets the American’s with Disabilities Act as supporting their view that genetic test screening in order to refuse employment is illegal.
Of even more concern is the possibility that entire groups of people may become socially unwelcome in society. There is fear that a genetic predisposition could become a stigma for groups within a society thereby making them outcasts amongst their peers. These and other concerns have threatened the benefits proposed by genetic research. Even the prevention of common genetically linked disorders cannot overcome the potential for the abuse of such information. If these issues go unresolved, then genetic technology may never achieve its full potential.
From page 300-306 Munson explains the Human Gene Program. The idea for mapping the human genome was first expressed and publicized by Robert Sinsheimer in 1985. Although it was first thought that the project would take 15-20 years and cost 3-5 billion dollars, it actually was finished in 11 years for less than 2 ½ billion, unusual for a government project! Part of the reason it got finished ahead of schedule is that the project got broken up and given to competing entities: one federal and one private. The two teams approached the task differently.
Knowing the order and sequence of DNA does not cure diseases but it does give us useful information that we are able to use in ever expanding ways. "Human DNA is now thought to contain about 30 thousand pairs, this is less than the 100 thousand previously thought..... this complete set of genes contained in the 46 chromosomes is known as the genome"
The genes responsible for about 1000 diseases have been identified, the book presents us with a sampling of them including a brief description of each: colon cancer, ALS, type II diabetes, alzheimers, X-linked SCID and then mentions a few more. Munson is careful to make clear that not every gene represents a definite manifestation of the disease, sometimes it is just a possible indicator. Although with some diseases it is clear.
He then mentions the Proteins project. DNA is made up of proteins and the Proteins project is similar to the Genome project in that it is a discovery mission.
Munson wraps up this section with a case presentation and an ethical dilemma. Huntingtons disease can be detected by a test but not treated. It is a neuromuscular degenerative disease that has its onset between the ages of 25-50 and kills within 15-20 years. The child of an affected person has a 50% chance of developing the disease. After diagnosis there is a high suicide rate. Munson tells us about a family that was affected and then spearheaded research to identify the gene. When they finally located the gene and were able to test for the disease they realized it raised more questions than it answered because there is no cure. Many people choose not to get tested and have a hard time deciding if they should test their unborn children.
In the next section (306-314) Munson explores genetic testing on fetuses and all that it implies. As was the case with Huntingtons disease many people thought that simply knowing about how to test for a disease would eradicate the problem, but it has raised many questions
First he explains that screening is not simple. For many diseases (like breast cancer) although there is a gene to screen for that is LINKED to breast cancer, it doesn't necessarily follow that if you have the gene you will develop the cancer, in this case the information is sketchy at best. He then goes on to outline situations in which information about a citizens genetics could be used against them. There is fear that employers would use a persons genetic information to discriminate in hiring practices. Although at first many companies said they would employ genetic screening if available, more recently they have said they wouldn’t, most likely they changed their position from public pressure. A more likely problem is health insurance companies using someone's (or their parents) genetic history to disqualify them from certain coverage.
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© Copyright Philip A. Pecorino 2002. All Rights reserved.
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