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Chapter 3 Genetic Control - Cengage

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Chapter 3 Genetic Control
Challenge of genetic control
It’s long been known that who we are depends in part on our environment and in part on our parents. This old and familiar idea was given greaterclarityand precision with the discovery of DNA as the chemical basis ofheredity.Thisincreased understanding also took a practical turn: within limits, we arebetter able totestiforthe genetic factors underlying diseases and even non-disease traits.Newfound knowledge and ability can result in new ethical questions.Theincreased understanding of genetics, and in particular, of the ability to test for particular genes, has resulted in a set ofethical questions, some of which are discussed in this chapter.
Section 1: Dilemmas of Genetic Choice
Genetic screening, counseling prenatal diagnosis, and embryo selection offer the prospect of avoiding the misery caused by crippling or fatal genetic diseases.Ifa genetic disorder can be detected before birth, it is possible to prevent the birth of children with those diseases. This would be of benefit to all including the children who might have been born.Yet, as positive as this outcome might appear, the possibility of genetic choiceraisesa number of troubling ethical issues, among them are:
Dilemmas of genetic choice
Diagnostic procedures themselves present a possible risk to the mother or fetus. When are those risks justified?In most cases in which prenatal diagnosis indicates that the fetus suffers from a genetic disorder or developmental defect, the only means of avoiding the birth of an impaired child is abortion.Butis abortion morally justified? If it is not, then is pre-natal genetic screening justified? (Chapter 5 examines the morality of abortion in detail.)
Dilemmas of genetic choice
A similar moral question arises in connection with embryo selection which is possible through In Vitro Fertilization.With this procedure,several of a woman’s eggs are fertilized outside her body and allowed to develop into early-stage embryos. During this time it is possible to screen the embryos for defects and to select only those which are free of them for implantation in the uterus.Whatare our moral obligations, if any, to the defective embryos not chosen?Prospective parents who learn through genetic testing that giving birth will possibly or likely result in an impaired child might decide nonetheless to go forward with the birth. Do they have right to do so?
Dilemmas of genetic choice
Children born with genetic diseases and defects require the expenditure of large amounts of public funds. Given these costs, is society justified in requiring that people submit to genetic screening, counseling, or prenatal diagnosis?Do physicians have an obligation to inform their patients who are prospective parents about thekinds ofgenetic tests that are available?Whatif a doctor is opposed to abortion and is afraid that his patient would seek one if the results of screening revealed a genetic defect?
Reading: The Morality of Screening for DisabilityJeff McMahan
McMahanreviews four common objections to prenatal orpre-implantationscreening for disabilities:screening is discriminatoryhas harmful consequences for disabled peopleexpresses a hurtful view of disabled peoplereduces human diversity.
Reading: The Morality of Screening for DisabilityJeff McMahan
If these objections show that screening is wrong, McMahan argues, they also imply that it is permissible to cause oneself to have a disabled child.Thosewho accept the objections to screening and claim that being disabled is no worse than being nondisabled seem committed to accepting that it is permissible to deliberately cause a disability prenatally, even for a trivial reason.If we find this view unacceptable, McMahan claims, then we must find the objections to prenatal screening for disability wrong.
Reading: Genetic Dilemmas and the Child’s Right to an Open FutureDena S. Davis
Davisasks whether genetic counselors must assist couples who wish to have a child who will be deaf or anachondroplasiadwarf.Taking deafness as an example, she argues that although counselors are professionally committed to an ethic of patient autonomy they may reject such a request, on the ground that it would limit the future autonomy of any child that might be born.
Reading: Genetic Dilemmas and the Child’s Right to an Open FutureDena S. Davis
Davis compares the situation with one in which Jehovah’s Witnesses refuse to consent to a lifesaving blood transfusion for their child and one in which Amish parents remove their children from school after the eighth grade.While courts have allowed the second, Davis sees both as unjustifiably denying children an “open future.”Whether or not deafness is considered a disability in a culture, being born deaf significantly restricts the choices open to a child. Thus, if it is chosen before birth by the child’s parents, it must be considered a harm. For this reason, genetic counselors should not help parents produce deaf children.
Section 2 Genetic Selection: A New Eugenics?
The goal of genetic screening is typically understood to be to detect geneticdefectsbefore birth.But, as our understanding of geneticsincreases,it may soon be possible to identify genes responsible forpositive traits, such as intelligence or good memory.Assumingthat this possibility becomes a reality, what should our moral stance be towardsselectingfor such traits (producing “designer babies”)?
Reading: Procreative Beneficence: Why We Should Select the Best ChildrenJulianSavulescu
JulianSavulescuargues that if tests for non-disease genes become available, we have a moral obligation to use them in making decisions about reproduction.Because disease-causing genes reduce the well-being of a person, what he calls the “principle of Procreative Benevolence” directs us to select against them. It isn’t the disease itself we are selecting against,Savulescuclaims, but its impact on a life. But non-disease genes can also have an impact. Intelligence, for example, can also affect well-being.
Reading: Procreative Beneficence: Why We Should Select the Best ChildrenJulianSavulescu
Thus, genetic information about qualities relevant to it should be used to select the embryo or fetus, with the aim of producing a life of the greatest well-being. Procreative Beneficence,Savulescuholds, must be balanced against Procreative Autonomy.Even so, doctors should try to persuade potential parents to seek out and use genetic information that will let them select for the greatest possible well-being in the life to be created.
Section 3: Genetics and Abortion
The goal of genetic testing is to provide information to doctors, patients and prospective parents so that they can make informed decisions.One kind of decision concerns possible medical treatments. For example, if a woman knows that she carries a gene (such as BRCA-1) which increases her chances of familial breast cancer, she might elect to have a radical mastectomy.
Section 3: Genetics and Abortion
Another kind of decision concerns whether to carry a pregnancy to term or have an abortion.The morality of abortion is a familiar question explored in depth in Chapter 5.In this section, the authors examine a narrower issue: abortion aside, are there any moral limits to the use of pre-natal testing?
Reading: Fetal Privacy and ConfidentialityJeffrey R.Botkin
Botkinargues for placing legal and ethical limits on prenatal testing.Awoman’s right to get information about her fetus, he claims, is not derived from the right to privacy, which justifies her decision to have an abortion. Rather, it is derived from the doctrine of informed consent.When she seeks prenatal care, she is entitled to receive information not only about herself, but about the health of her fetus.
Reading: Fetal Privacy and ConfidentialityJeffrey R.Botkin
Aswith other sorts of communication between a doctor and a patient, the information the doctor should disclose is subject to rational limits.Theselimits include protecting the fetus’s right to privacy, a right that must be balanced against the potential harm the birth of the fetus poses for the parents.Prenatal testing is justified,Botkinconcludes, when the harm the fetus poses is similar in magnitude to the birth of an unwanted child.
Reading: Implications of Prenatal Diagnosis for the Human Right to LifeLeon R.Kass
LeonKassexpresses concern that the practice of “genetic abortion” will strongly affect our attitudes toward all who are “defective” or abnormal.Those who escape the net of selective abortion might receive less care and might even come to think of themselves as second-class specimens.
Reading: Implications of Prenatal Diagnosis for the Human Right to LifeLeon R.Kass
Kasspresents six criteria that he suggests ought to be satisfied to justify the abortion of a fetus for geneticreasons.Hefocuses on the question raised by the last criterion: according to what standards should we judge a fetus with genetic abnormalities unfit to live?As candidates for such standards,Kassexamines the concepts of social good, family good, and the “healthy and sound” fetus.He finds difficulty with all, and in the end he professes himself unable to provide a satisfactory justification for genetic abortion.
Section 4: Embryonic Stem Cells: End of the Battle?
Embryonic stem cells are undifferentiated cells produced after a fertilized egg hasdivided severaltimes and developed into a blastocyst.Theblastocyst, a hollow ball of cells, containsa littlelump called the inner-cell mass consisting of fifteen to twenty embryonic stem cells.As development proceeds, embryonic stem cells differentiate and become specialized. They turn into so-calledadultstem cells. These cells go on to produce the approximately 120 different cell types.
Section 4: Embryonic Stem Cells: End of the Battle?
Before embryonic stem cells begin to differentiate, they have the potential to become any of the specialized cells. It is because ofthis potentialitythat researchers havethought they might be used to treatmany chronic, debilitating, and life-threatening diseases.However, because retrieving embryonic stem cells often results in the destruction of the embryo itself, some of the moral objections raised against abortion are also raised against embryonic stem cell research.
Section 4: Embryonic Stem Cells: End of the Battle?
But new research raises the possibility of being able to take a somatic cell, such as a skin cell, and “reprogram” it back to its earlier, undifferentiated adult stem cell status.As anadult stem cell, the cell could potentially be made to differentiate into any other cell type, as embryonic stem cells are able to do.The immediate appeal of being able to acquire human embryonic stem cells by converting somatic cells is the possibility that researchers will no longer need to create or destroy human embryos.
Section 4: Embryonic Stem Cells: End of the Battle?
Thus, the arguments over the moral legitimacy of stem-cell research and treatments based on stem cells should significantly abate, if not wholly disappear.But, as the readings in this section make clear, this promise is not as obvious as itmight at firstappear.
Reading: Stem Cells from Skin Cells: The Ethical QuestionsInsooHyun
Hyun argues that the genetic modifications of human skin cells to be like embryonic stem cells, though exciting, will not remove the ethical problems of stem cell research.First, induced pluripotent stem cell (iPScell) research will have to be carried out in conjunction with embryonic stem cell research in order to determine their value and safety for clinical applications.
Reading: Stem Cells from Skin Cells: The Ethical QuestionsInsooHyun
Second, the use ofiPScells will raise complicated issues of informed consent because they will be solicitedfrom gravelyill patients whose hopes might easily be exploited, as might, those of future patients who may seek treatments withiPScells.Finally,iPScell research may come up against the same questions about personhood as embryonic stem cells if it turns out that somatic cells can be programmed to generate supporting extra-embryonic (placental) tissues needed for the embryo to develop into a fetus or ifiPScells can be programmed to generate human sex cells.
Reading: Ontological and Ethical Implications of Direct Nuclear ReprogrammingGerard Magill and William B.Neaves
Magill andNeavesargue that the 2007 scientific breakthrough of producing induced pluripotent stem cells (iPScells) from human skin cells has ethical implications for how we regard natural human embryos, as well as embryos produced by cloning (i.e., somatic cell nuclear transfer.)TheiPScells share with embryos the potential to develop, given the right conditions, into a late-term fetus. Further research may show thatiPScells, like embryos, can also make their own placentas.
Reading: Ontological and Ethical Implications of Direct Nuclear ReprogrammingGerard Magill and William B.Neaves
This would make them indistinguishable in relevant ways from embryos (however produced).Thus,those who consider an embryo the moral equivalent of a person and seek to protect them must either extend the same protection toiPScells or change the criteria for personhood to ones that rely on features from a later state of embryonic development.Otherwise, defenders of the embryo-as-person view must reject usingiPScells for therapeutic purposes, in thesame waythat they reject the destruction of embryos and cloning.
Reading: Declaration on the Production and the Scientific and Therapeutic Use of Human Embryonic Stem CellsPontifical Academy for Life
The declaration by the Pontifical Academy sets out the official Roman Catholic position on the moral aspects of acquiring and using human embryonic stem cells.TheAcademy declares it is not morally legitimate to produce or use human embryos as a source of stem cells, nor is it acceptable to use stem cells from cell lines already established.
Reading: Declaration on the Production and the Scientific and Therapeutic Use of Human Embryonic Stem CellsPontifical Academy for Life
The Academy endorses the idea of directing research toward using adult stem cells to achieve the benefits that it is hoped embryonic stem cells might achieve.In 2008, the congregation for the Doctrine of the Faith issued “InstructionDignitasPersonaeon Certain Bioethical Questions,” in which it reaffirmed these positions and justification.

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Chapter 3 Genetic Control - Cengage