Genetic Screening

Jeff Olson

Copyright 1998

Imagine yourself as a 26-year-old pregnant female. You have just been genetically screened and you found out that you carry a gene for breast cancer. This gene almost always causes breast cancer in early adult hood. Your daughter-to-be has just inherited this gene. You have the following options; a) Abort the fetus and discontinue a disease that won't show signs for decades? b) Carry out the pregnancy and pray that your daughter is lucky and won't develop the breast cancer until maybe a cure for the disease has been found? This is a very tough situation to be in. This is just one situation of many that deal with a new era of a new concept called genetic screening or testing. Genetic screening is the testing of cells to check for certain kinds of genes, or for potentially damaging changes to those genes. It may be defined as a systematic search for persons with a particular genotype. The National Academy of Sciences recommends that genetics screening is an appropriate form of medical care only when certain conditions are met. These conditions include: (1) Evidence of substantial public benefit and acceptance; (2) The benefits outweigh the costs; (3) Appropriate public education can be carried out; (4) Informed consent is feasible; (5) The means are available to evaluate the effectiveness and success of each step in the process (Blank, 1982).

Genetic screening can be and is a difficult procedure, and the results depend both on reliable laboratory procedures and accurate interpretations of results. The interpretation of the test results is often difficult, even for the most experienced physicians and other healthcare specialists. When a person is investigating the results of any genetic test, one must take into account the probability of false positive or false negative test results ( Testing is currently being offered to individuals at all stages of life.

There are many types of genetic testing or screenings available to the public. These tests are used to detect possible diseases a person may have. Individuals may want to be tested if (1) there is a family history of one specific disease; (2) they show symptoms of a genetic disorder; or (3) they are concerned about passing on a genetic problem to their children ( Many of the genetic tests used today involve either medical or surgical procedures. Some types of genetic testing include the Carrier Identification genetic test. This test is used by couples whose families tend to have a history of certain recessive genetic disorders, and who are planning to have children. Cystic fibrosis, Tay-sachs disease and sickle-cell are three common diseases that are tested for in this area. A second test is the Prenatal Diagnosis test. This is a test of a fetus. The test is most often ran when there is a risk of parents bearing a child with genes that are associated with mental retardation or physical deterioration. A classical example is Down syndrome, which is the most common genetic disease screened by this method. A third test is screening of newborns. These tests are frequently done as a preventative health measure. Phenylketonuria (PKU) and congenital hypothyroidism are two diseases that are screened for in all states. A final type of testing is labeled Late-Onset disorders. These include adult diseases like cancer, heart diseases, or Huntingtons disease, which maybe seen later in life and may be tested for at any time (

Biochemists have located over 400 genetic markers distributed over all 23 human chromosomes ( A person may ask how are these biochemists able to locate and identify these genetic markers. One way is with the use of DNA probes. Probes utilize the complementary base pairing structure of DNA. The two individual strands of DNA can separate and rejoin in exactly the same sequence. A free-floating single strand of DNA binds only with the appropriate complementary sequence. The strands can be "labeled" to exhibit color, light, radioactivity, or resistance to antibiotics. When these fragments bind to their complement, the "label" identifies the target DNA sequence. From past research and "DNA libraries" molecular biologists know that certain probes bind to human DNA near certain genes (Genetics 431,1998).

A second way of locating these genetic markers is through restriction fragment length polymorphism (RLFP) analysis. This technique uses restriction enzymes to cut DNA into a series of fragments. The fragments are sorted by gel electrophoresis to form distinctive DNA fragment patterns. Each person has a unique pattern. The unique patterns occur when one of the two homologous chromosomes inherited form an individual's parents differ because of a mutation at a point where the restriction enzyme cuts the DNA. The identifiable pattern of fragments is called RFLP (Genetics 431,1998). Researchers examine the RFLP's of families with a known genetic disorder. Scientists hope to find a fragment pattern that is usually inherited with the disorder, meaning all people with the disorder have the same special fragment. This special fragment pattern is called a "genetic marker."

Public Policy Debates

There is probably no force in a society more powerful than the acquisition of information. The very essence of genetics is informative for individuals and their families. The need to know this information causes many problems. The area of ethics seems to play a big role and cause real problems. There are many ideas, both for and against the concept of genetic screening. This paper will take a look at a few of these debates.

The first problem that occurs is the true definition of a "disease." It has always been the norm to define deviations from the statistical norm, such as high blood pressure or obesity as "diseases." If a woman inherits a mutation of the p53 gene for example, and has an increased susceptibility to cancers of the epithelial cells, yet lives cancer-free for many years, does she have a disease? When the full human genome is mapped, we risk greatly expanding the numbers of people who do not fit our definitions of normal, able, and healthy.

A second ethical area of concern is genetic discrimination. People with genetic flaws, not all of which show up as dysfuctions, may be denied life insurance, health insurance, and access to schooling or jobs. Also along these lines, employers could hire only those people whose genes indicate they are resistant to the health hazards of the work place. Employers in most areas are not prohibited from requesting some type of genetic screening, even though there is not enough evidence to justify the use of any genetic screening test as a legitimate basis for employment decisions (Rothenberg et al., 1997). Genetic screening in the work place has caused a wide range of controversies. Employers are mostly in favor of this idea of genetic screening. They can use the information from the tests to ensure that employees are not placed in any environments that may cause the harm.

The people who support screening claim that it (genetic screening) would benefit everyone (employees, employers, and society). One report stated that 390,000 workers contracted disabling occupational diseases each year. Of these 390,000 diseases, 100,000 workers die ( If information was obtained through screening, the workers could avoid the hazardous to their health, found in the environments. In 1981, the Bureau of labor statistics reported that occupational illness costs private sector employers 850,000 lost workdays (

A final claim by supporters of genetic screening in the work force relates to health care costs. If there was a lower number of work related diseases resulting from genetic screening, society would benefit. We would benefit because health care costs covered by Medicare and Medicaid, public assistance, and social security payments would be lower.

Critics of genetic screening in the work place maintain that it violates workers rights and increases racial and ethnic discrimination in the work place. Secondly, critics say screening is a violation of an individuals right to privacy. A person's genetic make up is personal and private. If a employee shows no sign of a disease that could hinder his performance, there is no need to intrude on his/her personal life. Finally, critics argue that employers have an obligation to provide a safe work place for their employees (Rothenberg et al, 1997). This means that the employer should remove the occupational illness, not the victims that suffer as a result of the unsafe atmosphere. Bluntly stated, remove the hazardous substances at the work site, not the employees.

The area of genetic screening in newborns is also one of debate. Since 1962, most states have laws that make it mandatory to do genetic screening of all newborns ( "Newborn screening identifies biochemical or other inherited conditions that may produce mental retardation, other disabilities and or death." PKU and Congenital hypothyroidism is screened for in all states, and 42 states screen for sickle cell disease ( Many other diseases such as Galactosemia, Maple Syrup Urine disease, and Homocystinuria are also screened for in newborns.

Newborn screening raises various issues with regards to informed consent, privacy of genetic information, and confidentiality of test results. Who besides the patient and the physician should have access to the results? This is where there is a great deal of controversy. The requirement of parental consent for research use of the samples could be handled in several different ways: (1) the parent could be required to sign a consent form; (2) the samples could be used anonymously without consent, or (3) the individual could sign a consent form once he/she is old enough to understand the justifications of his/her decision.

Personal Opinion

First of all, I feel that the area of genetic screening is one of great controversy. There is a lot of convincing statements for and against the idea of genetic screening. I feel that it is valid to use genetic screening in certain instances (newborn testing) but I also feel that genetic testing can become another means of discrimination, especially in the work place.

First of all I will deal with the area of newborn screening. I agree with the concept of newborn screening. If newborn screening is mandated, doctors will be able to catch a serious if not fatal disease hopefully before it becomes deleterious. If the parents refuse to have newborn genetic screening and further down the road the child develops a disease that could have been treated if not stopped in his/her early developments, I believe the parents are liable and should have actions taken against them. From speaking with a few of my relatives, who have just recently had child births (in the last two years), they were glad that the technology was there to do the screening. They would have wanted to be able to take the preventative measures needed to provide an excellent environment for their challenged child. I feel the same way as they do. I was especially glad that my sister-in-law and brother had as much possible screening done as possible, for the fact that their two children are my nephew and niece. If something was to come up in the screening, then we would have been able to take the appropriate actions.

Secondly, I am against genetic screening in the work place. I believe that an employer should hire an employee on the ethics of what his/her qualifications are not what genetic disorders they may have. After all, it's the employee's qualifications, past work experience, and know how of the topic, that get the job done. I feel that failing to hire an employee on the grounds of genetic disorders is discrimination. I see hiring an employee on the grounds of his genetic disorders no different from not hiring an employee because of his religious background or his/her ethnic background.

Finally I believe that we need to exercise judgement in our pursuit of these technologies. We also need to understand the options that the new genetic technologies will offer so that we can make informed decisions at the individual, local, state, national and international levels.

Works Cited

1) Blank, R.H., 1982. Public policy implications of human genetic technology: genetic screening. Journal of Medicine and Philosophy. 7: 355-374.

2) Fackelmann, Kathy A. 1994. Beyond the Genome. Science News. Nov 5, pg. 298-299.

3) Genetics Class 431, 1998.

4) Newborn Screening to Prevent Mental Meturdation: obtained from the WWW 11/2/98:

5) Read My Genes: Genetic Screening in the Work Place: obtained from the WWW 11/2/98:

6) Rothenberg, Karen. 1997. Genetic Information and the Workplace: Legislative Approaches and Policy Challenges. Science. March 21, pg. 1755-1757.

7) The Gene Letter Volume 1, Issue 2, Sept 1996: An over view of Genetic Screenings and Diagnostic Tests in Healthcare: obtained form the WWW 11/2/98:

8) What is Genetic Testing: obtained from the WWW 11/2/98 11/2/98:

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