Human Genetic Screening

Debra L. Hudson

Copyright 1996

Human genetic screening is a process that is very complex and very powerful. Genetic screening may detect some inherited traits that may later on cause a person to have a disease that may alter his/her life. Human life, as with any other organism, is b uilt with cells. A human cell consists of forty-six chromosomes, which are paired into twenty-three different pairs. Each one of these chromosomes carries thousands of genes. Each gene consists of information that codes for a particular trait. This information is determined by the DNA found in that gene. A gene for one trait may have various alleles that will make one person appear a little different than that of a person with a different allele. An example would be of a person with brown hair. They would have a dominant allele for hair color, where as a person with blond hair would have two recessive alleles for hair color. It is possible to have a large number of different alleles for each trait, which is why people look so different from on e another (Reilly, Genetics, Law and Social Policy. p. 7).

“Although each person does have some variation in DNA, all members of the human species carry more or less the same set of DNA” (Griffiths, An Introduction to Genetic Analysis. p. 4). Because there is such a huge number of genes it is a very complicat ed process to isolate and identify the information in the DNA fragments. In these fragments it is possible for researchers to:

“ isolate and characterize at the molecular level single genes that are responsible for inherited genetic diseases. Genetic ill health can be divided into three major types. The first type is inherited genetic diseases caused by abnormal forms of genes that are passed on from one generation to the next. The second type is called somatic genetic disease, which is caused by the sudden appearance of an abnormal form of a gene in one part of the body. The third type is the chromosomal aberrations. This type is caused by abnormalities of chromosomal structure or number” (Griffiths, p. 5-6).

With the information that researchers have found studying the DNA patterns of those with certain diseases, they now may be able to determine if a person carries the trait that is found in common in these diseases by taking a sample of his/her DNA. “Genetics tests include techniques to examine genes or markers near the genes. Direct testing for diseases such as cystic fibrosis and sickle cell anemia come from an analysis of an individual’s specific genes. A technique called linkage analysis, or indirect testing, is used when the gene cannot be directly identified but can be located within a specific region of a chromosome. This testing requires additional DNA from an affected family member for comparison. Genetic testing results depend both o n reliable laboratory procedures and accurate interpretation of results. Tests also vary in sensitivity, that is their ability to detect mutations or to detect all patients who have or will get the disease. When interpreting the results of any genetic t est, one must take into account the probability of false positive or false negative test results. Special training is required to be able to analyze and convey information about genetic testing to affected individuals and their families” (Web site: #).

Genetic screening is a hotly debated topic. There are many different opinions as to how it should be handled. Some of the more positive thoughts are that genetic screening can help a person detect a disease early enough to be able to prevent it from al tering that person’s life in a major way as it would if it were not detected until it was too late for treatment. One example of this is a woman who carries a gene for breast cancer, BRCA1 or BRCA2, can be more aware of doing self examinations. It lets her doctor know that breast cancer is a possibility, so that he/she may do frequent tests to watch for signs of breast cancer. If breast cancer is detected early enough, many times it can be eliminated before it causes life altering effects (Masood, Nat ure. Feb. 1, 1996. p. 389).

Another positive aspect of genetic screening is that “using recombinant-DNA techniques, scientists have tested DNA isolated from cells of unborn babies to learn whether the babies will have a disease. Doctors may eventually be able to treat babies in th e womb to prevent a disease (The World Book Encyclopedia. p 85).” I found in a survey that questioned different peoples’ opinions on whether or not someone has the right to know if they have a gene for a disease that, many of them said yes. They felt that a person has the right to know because it is their life, and they have the right to deal with the future in the way they want to (Web site: Having the information that a person has a ge ne for a fatal disease may help that person live a fuller life. If they know they may not have as much time as they had planned, they may go out and make the most of the time they do have. Just helping one person live a better life is a positive result.

Although there are positive aspects to genetic screening, there are definite negative aspects. Genetic screening causes a lot of ethical questioning. Many people fear that researchers are trying to play God. Many feel that people are not supposed to k now their fate, and are to live their life as it comes to them. Also genetic screening is still being questioned to its accuracy.

“Predicting more common disorders such as breast cancer and cardiovascular disease, which are more likely to be of interest to health and life insurance companies, will be more challenging, as they involve several different genes. For example, mutations in five separate genes are known to increase an individual’s susceptibility to colon cancer. Similarly, mutations in at least two genes are known to predispose to breast cancer. But the absence of such mutations does not necessarily mean that the perso n who has been screened will not develop either disease. Take breast cancer one in ten women living in Western societies is likely to develop breast cancer by the age of eighty-five and twenty-five per cent of these sufferers will die from the disease. About five per cent of breast cancer cases are hereditary. But mutations in the two known susceptibility genes, BRCA1 and BRCA2, account for only eighty per cent of all the hereditary cases. As a result, genetic tests for BRCA1 and BRCA2 will not be of any value to the remaining twenty per cent of women predisposed to breast cancer, and will be even less informative about the ninety-five per cent of cases that are not hereditary” (Abbott, Nature. Feb. 1, 1996. p. 390).

It has also been said that not even the most educated of the researchers can say with much accuracy whether or not a person will contract “polygenic and multi factorial diseases” (Abbott, p. 390). It has also been found that some researchers do not take responsibilities of making sure they are credible.

“ A study showed that academic laboratories were less likely than companies to have undergone any external quality review. Out of about a hundred non-profit laboratories providing molecular genetic services, sixteen had not registered as required under t he federal Clinical Laboratory Improvement Amendments or participated in any proficiency testing. At least one geneticist said he felt his published discoveries were sufficient to demonstrate the quality of his laboratory, and that certification was unne cessary (Lehrman, Nature. Nov. 9, 1996. p. 121).”

Another very negative aspect to genetic screening is that “ knowing your genetic makeup can also create profound emotional and financial problems. For example, a spouse might use this information in a custody dispute. Or a woman might decide not to hav e children for fear of passing on the gene. But if she decides to adopt, will she be approved by an agency? (Koenig, The New York Times. April 6, 1996. p. 15)”. Is this a fair thing to put a person through? No one really has an answer, but in real ity a person may suffer because their genetic makeup for a possible disease has been made available. It is not definite that the person will develop the disease, so why should they live their life as though they will have the disease. A woman may abor t a perfectly healthy baby just because they think it might get a disease because of genetic makeup. Is that fair to a baby that may have been created in love? Many of these aspects relate back to morality. It all depends on how someone feels about the ir ethical standings on genetic screening.

One final aspect that may be the deciding factor on whether or not to be screened is the insurance situation. Many insurance companies are pushing to be able to have access to genetic screens that their clients have had, and some are pushing for clients to have screening done in order to get an insurance policy. If life insurance agencies are made aware of a possible genetically inherited disease that is fatal, it is very possible that they will raise the costs of insurance, or not insure a person at all. This makes it very difficult for people who are screened positive for a gene for some disease. If for some reason this person dies of another cause early in life, what is their family to do? If it is a single mother whose husband dies in an accide nt, will she be able to handle the bills? There would not be insurance to help her out because he could not get insurance due to his screening of a fatal gene. “ As of now the United States has no restrictions on life insurers’ request for genetic test s. Life insurers have successfully lobbied to ensure that companies are not prohibited by state laws from having access to genetic information. But Kenneth Vest, a spokesman for the American Council of Life Insurance says his organization’s members do n ot ask prospective policy-holders to take tests (Masood, p. 389).” There are some companies who are trying to work out a fair situation, but there are still a lot of questions.

Now that I have researched information on this subject I have found that I have changed my opinion on genetic screening. I once believed that as long as one person was helped by the genetic screening, then it was worth all of the negative side effects. I do not believe that any more. I feel that knowing your genetic makeup can only cause you a lot of problems. These problems are not only for yourself, but your family as well. Not being able to get insurance is a really important thing to think abo ut. If I was to get killed in some way such as a car accident, or a plane crash, I would not want my family to suffer financially. I plan to have children, and I do not want them to have to pay financially because I wanted to know my fate. Losing a par ent is hard enough on a child, they should not have to suffer other ways on top of it.

Another aspect that really bothers me is that there is not really a way to be certain that a gene that I am screened positive for is ever going to affect my life. I think it would be hard on my husband to know that some day I may die because of a fatal disease. My husband as well as myself would spend more time worrying about what will happen if I do die, than what is happening while I am healthy. I know that many people will not react the way I do, but I believe that there are quite a few that will react the same. I would also be very angry if I put out the money to have a screening done, and the results that I received were wrong. That would be awful. To spend the rest of your life being scared that you are going to die of a disease, or suffer from a less serious disease, and then to never experience any side affects of the disease would be such a waste of the happy life I could have led. I would definitely try to find a credible doctor, but from the research I have found, some of the most ac claimed doctors cannot guarantee the results are absolutely correct. That is a flaw I find just repulsive. I feel that unless the results of a test are backed up with an absolute assurance, then the test should never be given.

The final aspect that probably turns me off the most now is that I do not think that our DNA makeup should be tampered with. DNA is what makes up a person. It is what decides what that person will be like. Once that is changed, the person is changed a s a whole. I believe in medicine to a point, but I do not believe in changing fate. When it comes to my physical make up I want to be left exactly the way I was when I was born. That is the way I was meant to be. Everyone has the right to do what they want with their life and their bodies, and I would never stand in the way of a person’s rights, but I myself have decided that genetic screening is not something that I want in my life. I want to just take life one day at a time. If I get sick, I will deal with it when I am actually sick.


Abbott, Allison, Nature. Complexity Limits the powers of prediction. Feb. 1, 1996: p. 390.

Griffiths, Anthony, Jeffrey miller, David Suzuki, Richard Lewontin, William Gelbart, An Introduction to Genetic Analysis, Sixth Edition. W.H. Freeman and Company, 1996: p. 4,5-6.

Koenig, Barbara, The New York Times. Gene Tests: What You Know Can Hurt You. April 6,1996: p. 15

Lehrman, Sally, Nature. Genetic testing needs more checks. Nov. 9, 1995: p. 121.

Masood, Ehsan, Nature. Gene tests: who benefits from risk? . Feb. 1, 1996: P. 389.

Reilly, Phillip, Genetics, Law, and Social Policy. President and fellows of Harvard College. 1977: p. 7.

The World Book Encyclopedia, 1993 Edition, 1993 World Book Inc. 1993: p. 85.

Web Site #1 Written by: The Exploratorium , 3601 Lyon St., San Francisco, CA 94123

Web Site #2 Written by: The Exploratorium, 3601 Lyon St., San Francisco, CA 94123

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