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UNIT
ONE Communities & Genetic Testing Ashkenazi
Jewish Community The
Gay Community
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The completion of the mapping of the human genome, has created hopeful new medical possibilities, but has also raised serious ethical and legal concerns. With this knowledge of the whole human genome, one can identify mutations that might predict the onset of a disease, and identify individuals that might hold such markers. With recent advances in genetic science, the future holds treatment possibilities found in new drugs and/or gene therapies for treating and/or preventing the disease. At the same time that we are encouraged by the numerous health benefits to be gained from genetic testing, there is also a fear for the abuse of the genetic information revealed. This fear is especially prominent in communities with unique genetic markers. In this case, individual members in one such community provide information about the genetic code of all other members without their consent or knowledge. As a result the entire community will experience both the positive and negative effects this testing might hold. In this section, I will concentrate on the Ashkenazi Jewish community and the gay community in particular. Who are the Ashkenazi Jews and why are they a target for genetic testing? The Ashkenazi Jews are those of Eastern European
origin and constitute more than 80% of all Jewish people in the
world today. They are unique population because they demonstrate
a very homogenous genetic code. This is due to the founder effect.
Founder effect is when there is a loss of genetic variation due
to a very small number of individuals forming a new colony. As a
result the small population experiences dramatic inbreeding which
leads to the greater expression of otherwise rare combinations of
genes. This, in turn, can lead to an increase of diseases found
in a community. More specifically, these Jews experienced the founder
effect because the entire population emerged from a small number
of founders almost exclusively limited to a long history of marriage
within the family and within the faith. In addition, there was an
unequal reproduction rate between the social classes. As a result,
the current Ashkenazi population did not originate from all of the
founders living many centuries ago, but selectively from a small
fraction of wealthier people. There are several rare diseases that
occur with a particularly high incidence among Ashkenazi Jews. What are the diseases that effect the Ashkenazi Jewish population? In the Ashkenazi Jewish population, it is estimated that one in seven individuals is a carrier for one of six genetic conditions. Some of these diseases are severe and result in the early death of a child. The diseases that are more frequently seen in the population are: Bloom syndrome, Canavan disease, Fanconi Anemia, Gaucher disease, Nieman-Pick disease, and Tay Sachs disease. Bloom Syndrome: Approximately one out of every one hundred Ashkenazi Jews is a carrier for the disease. Canavan Disease: Canavan disease is a severe degenerative disease of the central nervous system. It is caused by the lack of the enzyme aspartoacylase (ASPA). ASPA is responsible for the breakdown of the substance N-acetylaspartic acid (NAA). When ASPA is absent, NAA builds up in the brain causing brain damage, mental retardation and other symptoms associated with the disease. At birth the child appears to be normal. It is not until the child reaches three to five months in age that the parents will begin to notice changes in the child. For example, the child will not be able to roll over or grasp objects that they had once before. Eventually these children become blind, and have trouble swallowing. Death occurs by age five. One out of forty Ashkenazi Jews is a carrier for the disease. Fanconi Anemia: Fanconi Anemia is characterized by a reduced number of all types of blood cells in the body, leading to bone marrow failure. Those that suffer from Fanconi Anemia may have the following symptoms: missing bones in the thumbs or arms, increased risk for cancer and leukemia, brown coloring to the skin, kidney problems, or small head and eyes. Ultimately, Fanconi anemia affects all body systems. Patients with this disease rarely live to adulthood. It is estimated that one out of every 87 Ashkenazi Jews is a carrier of this disease. Gaucher Disease: Gaucher Disease takes three forms – Type I, II and III. Type I is the most common form with one out of ten Ashkenazi Jews being a carrier. It is caused by a lack of an enzyme known as glucocerebrosidase. This enzyme breaks down fatty substances in their cells. With glucocerebrosidease absent this fatty substance accumulates in the liver, spleen, bone marrow and other parts of the body. This accumulation leads to the signs and symptoms of Gaucher disease. Unlike the other diseases talked about so far, the signs and symptoms of Gaucher disease vary greatly and can appear at any stage in life. Symptoms of the disease include: bruising, bone pain, anemia, frequent nosebleeds, lack of energy, and frequent fracturing of bones. While there is no cure for Gaucher disease, there are treatments available that can lead to an improved quality of life for those affective individuals. Treatment includes the intravenous enzyme therapy of a form of the gulcocerebrosidase, and treatments that relieve the symptoms. Nieman- Pick Disease: There are four types of Nieman- Pick disease- types A, B, C and D. Type A is more common within the Ashkenazi Jewish population with an estimated one in every 75 Ashkenazi Jews being a carrier. As a result Type A will be focused on here. Nieman- Pick type A occurs from a lack of an enzyme called acid sphingomyelinase or ASM. ASM is responsible for breaking down a substance in the body known as sphingomyelin. With ASM missing, sphingomylein is free to accumulate in cells causing damage to the central nervous system, liver and lungs. Nieman- Pick Type A is a severe neurological disease that results in death by age two or three. At birth there is no evidence of the disease; however, at about three to five months in age the first clinical symptoms present themselves. These symptoms include: a progressive loss of early motor skills, feeding difficulties, a large abdomen, blindness, an enlarged liver and/ or spleen, a “cherry red spot” in the eye, and jaundice in infancy and progressive liver failure later on. Tay Sachs Disease: Tay Sachs disease is the most well known of Jewish inherited diseases caused by a metabolic disorder. Those that have Tay Sachs disease lack and enzyme in their body called hexosaminindase A (Hex A). Hex A is responsible for breaking down a certain type of fat in the body called GM2 ganglioside. When Hex A is absent from the body, this fat can accumulate to toxic levels in the body mainly in the brain and nervous system. Tay Sachs disease takes two forms, infantile and late-onset Tay Sachs, and in each causes progressive degeneration and destruction of the central nervous system in affected individuals. In infantile Tay Sachs, babies born with the disease appear to be normal at birth and develop normally until they are about six months of age. At this age the first signs and symptoms of Tay Sachs develop. Initially, development slows, children lose previously attained skills like rolling over or sitting up. Then they gradually lose their sight, hearing and ability to swallow. By two these children experience recurrent seizures and a diminished mental status. There is no cure for Tay Sachs. As a result, these children die between ages 4 to 8. In late- onset Tay Sachs, adolescents and adults of Ashkenazi Jewish heritage experience a significant reduction of Hex A. About five to fifteen percent of Hex A activity remains in these individuals compared to a complete absence of the enzyme in infantile Tay Sachs. The progression of the neurologic symptoms is much slower in these individuals due to the slower accumulation of GM2- ganglioside in the brain and nervous system. Symptoms of the disease include slurred speech, tremors and poor coordination. It is estimated that one in every 25 Ashkenazi Jews is a carrier for this disease. Other Diseases for which there is increased risk to the Ashkenazi Jewish community: In addition to those diseases referred to earlier, there is also an increased risk for other types of cancer within the Ashkenazi Jewish community. These cancers include breast cancer, ovarian cancer and colon cancer. While breast cancer itself is not hereditary, an increased predisposition for contracting the disease is. An increased predisposition is traced to a gene on chromosome 17- BRCA1 and a gene on chromosome 13- BRCA2. Those women who inherit mutant forms of BRCA1 may have up to an 85% risk of contracting breast cancer and a 44% risk of contracting ovarian cancer in their lifetimes. This compares with an overall 12% risk breast cancer and 1% risk of ovarian cancer in the general population. In other words, not all people who possess a mutant BRCA gene will get breast cancer; however, having the gene makes getting breast cancer more likely when compared with those without the faulty BRCA gene. It has been found that Ashkenazi Jewish women possess genetic markers for both breast cancer and ovarian cancer at a high frequency rate. It is now estimated that one out of fifty Ashkenazi Jews carries a mutant copy of BRCA 1 or BRCA 2. Although other types of mutations in BRCA1 and BRCA2 do exist in the general population, the two specific mutations associated with Ashkenazi Jews have not been found in the non-Jewish population. This has precipitated a call for genetic testing for all breast and ovarian cancer victims. For additional information on these diseases, screening processes and treatment options see: http://www.mazornet.com/genetics/index.asp What are some problems associated with Genetic Testing? It seems obvious from the number of inherited diseases afflicting the Ashkenazi Jewish community that they would want continued genetic testing to occur. Not only does the information derived from such testing benefit the Ashkenazi Jewish community but the entire human race. The more that is known about a particular disease, the better the chances for finding a cure or improved course of treatment will increase as well. However, this knowledge is not confined to the scientific community. Upon typing in Ashkenazi Jews into the Google search engine, all of the statistics about how many afflicted Ashkenazi Jews were readily available. While I was using this merely as a source of information, insurance companies can use this information to adjust their premiums paid by Ashkenazi Jews. Employers can use this information to exclude hiring Ashkenazi Jews based on their genetic risk factors. Those considering marriage to Ashkenazi Jews might use this information to reconsider their choice about marriage or having children with him or her. How can this community be protected from insurance, employer and marital discrimination? Genetic testing is still new and legislation has not caught up to protect the rights of the community. It is unclear right now whether or not the federal law Americans with Disabilities Act will protect employees from discrimination based on their genetic risks. In any event, the ADA addresses workplace discrimination, but not privacy. There is currently no federal law, which prohibits an employer from requesting genetic information or testing employees, and no law protecting the privacy of genetic information. The Ashkenazi community is well aware of the risks, and benefits associated with genetic testing and wants to ensure the maximum benefit while minimizing the risk. As a result Jewish groups have banned together in an attempt to pass legislation. One example of this occurred in 1997 when the Jewish Council for Public Affairs adopted a Resolution on Genetic Testing, Discrimination and the Jewish Community. In this resolution they stressed the desire for the Jewish community to continue their participation in research developments. At the same time the council addressed the need “to develop public policy and legislative strategies regarding the use of information provided by genetic testing; support legislative measures, at both the federal and state levels to prevent genetic-based employment and insurance discrimination and to ensure the confidentiality of medical records.” Another example is Judith L. Palkovitz, National Vice President, Hadassah, who spoke before the Committee on Labor and Human Resources about the issues effecting the Ashkenazi Jewish community. She too addressed the growing concern of the Jewish community to be protected. Within the speech she cited the New York Times article which quoted the Rabbi Moshe Tendler, renowned medical ethicist at Yeshiva University as saying “he would discourage Jews from participating in research until protections are passed.” The Jewish community has received this message. The Associated Press cited a National Institute of Health study in which 32% of women who were asked to participate in the breast cancer genetic mutations research actually declined. Most of these women cited fear of discrimination and a loss of privacy as their reasons for not participating in the research. She ended her speech with the following which is something that we should all contemplate and keep in mind as genetic testing progresses: “No one should have to make the choice between health information and health care. No one should lose a job because of their genotype. The pace of life-saving cancer research should not be slowed because potential subjects are too afraid to participate…. Hadassah urges you [Mr. Chairman and members of the Committee] to act now to insure that genetic science advances, rather than limits health care options for all Americans.”
The human genome project has told us that looking beyond race, culture, religion, disability, disease or any other factor the human genome is virtually identical. In other words, it is estimated that 99.8 percent of all the human genome is the same in every one of us. This is even truer when it comes to talking about a homogenous community like the Ashkenazi Jews. An important issue is raised here.
Issues Raised by Genetic Testing in the Gay Community I would like to start this
portion by posing a question to you. Would you respond to the following
advertisement? This is a similar copy of an advertisement ran in gay newspapers in the Baltimore and Washington D.C. area when Dr. Hamer and his associates began their search for what made gays gay. (Hamer, 49) Before answering the posed question, please consider the other people that will also be included/ effected by your decision to partake. The advertisement asks for you and your brother. So now it has gone from an individual decision to a decision including another person. This is stated in the ad. However, what is not stated in the ad is that the researchers have to gain your permission to contact 79% or your living relatives to confirm your sexual orientation. The decision has now spread to the majority of your family members. Also keep in mind, that because you belong to a unique community, sharing your sexual orientation in common, that the genetic information that you provide will also give the researchers information about your neighbors, friends and peers. You can gain consent from your brother, you can gain consent from your family, but you cannot gain this same consent from your entire community. Other members in your community might not want to know if a “gay gene” exists, but by participating in the study you essentially make the decision for them. This is the same issue that was raised when we discussed the Ashkenazi Jewish community.
What the gay community has to say about genetic testing? There are currently two factions within the gay community- those that want genetic testing and those who oppose genetic testing. Those who want genetic testing feel that if a “gay gene” is found then there is no personal choice involved in their sexual orientation; they were born that way. Therefore, being gay is unchangeable- a normal variant of human nature. The Catholic Church argues that homosexuality is wrong because the people in the gay community made a wrong choice. However, if it is found that no choice is involved and sexuality is innate the way race and sex is innate, then homosexuals should be afforded the same kinds of protection against discrimination that women an minorities have. In other words, they will be afforded the same rights and protection as other minority groups. Those who are opposed to genetic testing feel that the discovery of the gay gene will lead to the society’s looking at homosexuality as something that has to be eradicated. This portion of the gay community feels that the discovery of a gay gene will lead to gene therapy to eliminate fetus that can potentially become homosexuals, or that an amniocentesis can be carried out and that a fetus can be aborted having such a gene. In this way the homosexual community will just die out. The following cartoon describes such sentiments:
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It is obvious that the split in the gay community is large, and the consequences of genetic testing are unknown. Is it the right of those who believe that the discovery of the gay gene will lead to equal rights for homosexuals to give their genetic information on behalf of the whole community? Dr. Dean Hamer, the first researcher to publish his findings about the gay gene, has this to say about the implications of the discovery of a gay gene: “Concepts like ‘good and bad’ or ‘right and wrong’ do not appear in biology textbooks. Nevertheless, there seems to be an almost irresistible urge for people to try to use biology either to condemn or justify homosexuality (and other human behaviors). They talk about what’s natural and what’s not, or what makes evolutionary ‘sense.’ None of the arguments really resolves the issue.” (Hamer 213)
Billings, P., et al. "Discrimination as a Consequence of Genetic Testing," American Journal of Human Genetics. 50 (1992): 476-482. Hamer, Dean & Peter Copeland (1994), The Science of Desire: The Search for the Gay Gene, Simon and Schuster Publishing, New York http://gos.sbc.edu/p/palkovitz.html http://www.hadassah.org/news/ascene/fall98/jewish.htm http://www.jewishpublicaffairs.org/security/resolutions/genetic_testing-6-27-97.html http://www.mazornet.com/genetics/index.asp Personal Communication with Dr. Lainie Ross
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