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Cloning. Biotechnology and Bioethics. Red Light? Yellow Light? Green Light?. The federal administration has issued regulations banning all cloning human tissue in any facility or effort funded with federal dollars.
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Cloning Biotechnology and Bioethics
Red Light?Yellow Light?Green Light? • The federal administration has issued regulations banning all cloning human tissue in any facility or effort funded with federal dollars. • The House of Representatives passed legislation banning all forms of cloning in the last session, however the bill stalled in the Senate. • The state of California has passed legislation, and Governor Davis has signed it into law, that bans reproductive cloning, and explicitly endorses therapeutic cloning. • In December, 2002, the American Bar Association endorsed cloning for cures, or therapeutic cloning. • In December, 2002. Stanford University launched its Institute for Cancer/Stem Cell Biology and Medicine with a $12 anonymous donation, and will proceed with cloning for stem cells. The Center’s director, Dr.Irving Weissman, said, “Our avowed goal is to advance science.”
? Questions ? • Is cloning a GO, a SLOW GO, or a NO GO? • What is cloning, anyway? • What is the difference between therapeutic cloning and reproductive cloning? • What are stem cells and what is their relationship to cloning? • What is the significance of cloning; why would people want to clone anyway? • What are the objections to cloning? • Is cloning an ethical issue? • Is cloning a religious issue? • Is cloning good or bad—right or wrong?
The Science of Cloning • Cloning is another word for copying. • Identical twins are clones, copies created when a single zygote splits into two in the uterus. • Scientists have now been able to create genetically identical copies of animals separated by a generation--clones. • On February 23, 1997 the news broke that Ian Wilmut, a Scottish scientist and his colleagues at Roslin Institute, were successful in cloning a sheep—Dolly. • Dolly was the genetic equivalent of the adult sheep from which she was cloned. • Since then scientists have successfully cloned mice (1997), a cow (1998), a pig (2000), and a cat (2000). • Work is now underway, internationally, to clone a human being; and it is anticipated by some that such could happen in the not too distant future, though there is much disagreement about the possibility.
How Does Cloning Work? • An unfertilized donor egg (a reproductive cell) is taken from a woman, in much the same way that it would be accomplished if an in vitro fertilization was planned. • The nucleus of the egg, which contains all the genetic material of the woman, 23 chromosomes, is removed. • Humans have a total of 46 chromosomes, with 23 coming from the mother’s egg and 23 coming from the father’s sperm. • Another cell—this time a somatic cell, that is, a cell from any part of the body, such as heart, nerve, or skin, is extracted from a person. This cell contains all 46 of the human chromosomes, the same number that are in every other cell of this person—the person’s total genetic endowment.
Transferring the Nucleus • One of two methods is used to transfer the genetic material from the somatic cell to the gutted master egg cell—which now has no nucleus or genetic material (DNA). • The whole somatic cell is fused with the gutted egg using a jolt of electricity. This places the genetic material (chromosomes) of the nucleus of the somatic cell into the egg, or • The nucleus of the somatic cell is removed with a micropipette and injected into the empty egg. • The egg now contains all the nuclear material, 46 chromosomes, all from the somatic cell of donor. • Regardless of which method is used, a jolt of electricity, or a mixture of chemicals, trick the egg into starting to divide into an embryo. • This process is known as Somatic Cell Nuclear Transfer, frequently abbreviated SCNT.
Reproductive VersusTherapeutic Cloning • Cellular division of the zygote results in the formation of a hollow ball of about 100 cells, called a blastocyst. This requires approximately five days. • If the blastocyst is inserted into the uterus of a surrogate it could implant and develop into an embryo and subsequently a fetus. This process is identical to in vitro fertilization where the egg and sperm are fertilized externally and then inserted into the mother’s uterus. In the case of cloning the resulting baby would be virtually genetically identical to the donor of the somatic cell, whether it was the mother who carried the cloned child, another woman, or another man. • But, the baby will not be an exact replica—due to the existence of a small amount of mitochondrial DNA, as well as a different environmental exposure in the uterus. • This is reproductive cloning.
Reproductive VersusTherapeutic Cloning • In therapeutic cloning the “stemcells” are removed from the blastocyst and the remaining cells destroyed. The blastocyst is never inserted into a uterus and permitted to develop further. • Stem cells are the primitive cells that are the precursors for all of the varied cells that ultimately develop to form our body’s tissues and organs. • Scientists believe that these primordial stem cells can be stimulated in culture to form into any cell of the human body. • They could then be: • Transformed into islet cells and could restore function to a diabetic’s pancreas. • Morphed into nerves that could replace the diseased neuronal tissue of those who have suffered strokes, spinal cord injuries, or other neurological diseases such as ALS, multiple sclerosis, Alzheimer’s or Parkinson’s disease. • Used to grow skin cells to provide a ready supply of tissue for burn victims. • Grown into cardiac tissue to shore up damaged arteries and hearts.
Reproductive versusTherapeutic Cloning • Whether of not they support therapeutic cloning or not, essentially all mainstream scientists acknowledge that they are opposed to reproductive cloning. Based on the experience in animals, many scientists believe human reproductive cloning could be dangerous for the woman and the baby, and potentially fatal.
Stem Cell Research • Therapeutic cloning is about stem cell research. • It is about developing multiple genetic lines of stem cells through the process of therapeutic cloning, in order to advance our understanding about how these cells develop into the huge variety of specialized cells that make up the human body. • And, it is about determining how we can transform these cells into reparative cells for treating human disease and disabilities. • Currently the federal administration has banned such therapeutic cloning in federal facilities or with the use of federal dollars. • Why?
Bioethics • Bioethics is that field of applied ethics that is concerned with ethical issues of biological life. • Ethics is the “science of the moral.” It is about good versus evil, and therefore is about what is right versus what is wrong. • Actions that result in harm or evil to others are typically understood, both philosophically and religiously, to be wrong. • Actions that result in good for others are typically understood, both philosophically and religiously, to be right.
Bioethics • While opposition to reproductive cloning can be understood at this time due to the scientific uncertainty regarding the effects it could have on either the mother or the cloned child, it is difficult to understand why opposition exists to therapeutic cloning, which is being employed to conduct stem cell research in the laboratory; research that will potentially result only in doing good for others by helping to heal diseases and disabilities, and in some instances prevent death. • On the surface, this appears to be nothing more than appropriate scientific research to help the human condition. • BUT . . .
Another Agenda • To use the words of Art Caplan, Director of the Center for Bioethics at the University of Pennsylvania, “an alliance of abortion opponents, social conservatives and biotechnology-phobes wants you to believe that human cloning is always unethical, even when it’s done for the purpose of finding cures for horrible diseases. It isn’t.” Caplan goes on to say therapeutic cloning is not only not unethical, but that it is unethical not to proceed with therapeutic cloning for research purposes. • To understand objection of these groups, and to appreciate the breadth of polarization in our society on this issue, it is necessary to grapple with a very basic issue, which is at the heart of the controversy. . . the issue of personhood.
Abortion • There is probably no more divisive issue in our society than the issue of abortion. • Interestingly, so much misunderstanding of human therapeutic cloning is based on the ongoing battle over abortion. • Foes of abortion have mounted the claim that a person is a person from the time fertilization of the egg occurs by the sperm, therefore arguing for protection of this ‘human being’ by law from this point onward. • Granting the fertilized ovum such status would then preclude any abortion, as one would be guilty of murdering a person, a human being’; such would also be the case with the use of emergency contraception. • Extending this argument to its logical conclusion, these individuals argue that in cloning as soon as the nuclear material is transferred to a gutted egg, you now have a fertilized ovum—a ‘person.’ • To then allow this ‘person’ to develop into a 100 cell blastocyst in a laboratory petri dish, extract the stem cells, and then destroy the remaining blastocyst, is to be guilty of homicide. • This is also the position of the current federal administration, and the reason for banning therapeutic cloning. It is unknown whether the President actually believes this, or whether he is responding to the political pressure of his constituency on the religious right. • Of note is the fact that when in vitro fertilization is accomplished today--to assist a woman in becoming pregnant--multiple eggs are fertilized, and the excess fertilized eggs discarded when no longer needed. Taking the aforementioned stated position, ‘people’ are killed regularly in this practice, yet it is not only not illegal, but is accepted and condoned by society to help women become pregnant.
Personhood(Biological Facts) • Pregnancy begins when the zygote implants in the woman’s uterus. • As an aside, when discussing this topic many individuals on both sides of the debate identify the fertilized egg as an embryo. This is incorrect. The zygote does not become an embryo until certain developmental changes take place—approximately two weeks after fertilization. • Many individuals also believe that pregnancy begins with fertilization. This is not true either. Pregnancy does not begin until the zygote implants in the wall of the uterus, approximately seven days after fertilization. • It is estimated that nature has already aborted approximately 55% of all fertilized eggs (zygotes) before actual pregnancy begins; likely due to genetic abnormalities. • The incidence of miscarriage, the spontaneous abortion of the embryo or fetus after implantation is approximately 12%.
Personhood . . .Implications of theBiological Facts • If a person is defined as the resultant of the fertilization of an egg, multiple problems are created. Over one-half of these ‘persons’ die. If granted the legal prerogatives of personhood, population and mortality statistics rise dramatically. Implications for determining actual age, number of dependents, income tax deductions, funerals and burials, and all things legal related to existence and age become very significant and problematic. • The current federal regulatory ban of therapeutic cloning is essentially defining that which exists immediately following the transfer of the nuclear material from a donor somatic cell to a gutted egg as a ‘person.’
Philosophical Issues in Defining a Person • While the biological facts would seem to make a persuasive argument for the unreasonableness and impracticality of designating a zygote a person, there are philosophical reasons to not do so as well. • The central argument of those arguing that a cloned egg/zygote is a person is: • First premise: All human beings (persons) deserve equal protection and equal rights under the law. • Second premise: The cloned egg/zygote is a human being/person. • Conclusion: Therefore, the clone egg/zygote deserves equal protection and equal rights under the law. • However, the second premise cannot be sustained.
Philosophical Issues in Defining a Person • In the strict philosophical sense, that is, the moral sense, what distinguishes a person, is that persons are self-conscious (self-aware), self-determining, and rational; able to communicate and use language. • Additionally, persons have the ability to make moral judgments, that is, able to be concerned with praise and blame for behavior. • It is these characteristics of humanity that we do and should value, not merely the existence of human tissue. • We also use the term person in a broader sense to refer to individuals who have a sense of self and are capable of interacting with other human beings. • Thus, we assign psychological or social personhood to human beings whom we are able to see, speak to, respond to, and who can see, touch, speak, and respond to us—individuals who are “alive and aware.” In general, human beings with whom we can interact socially. • Historically, societies have granted personhood, in this sense, beginning at birth.
Philosophical Issues in Defining a Person • Some wanting to create personhood for a cloned cluster of cells want to argue that the cells should be accorded the rights and protections of a person, even though technically not a person, because they are potentially a person. • But, that which exists in potentiality does not exist in actuality. If X is potentially Y, it follows that X is not Y. Therefore X does not have the rights of Y, but only potentially the rights of Y. If X is potentially a President, it follows from that fact that X does not yet have the rights and prerogatives of the President. • An acorn is not an oak tree, only potentially an oak tree. The fertilized egg of a chicken is just an egg, not a chicken.
Religious Issues in Defining a Person • The predominant advocates for assigning personhood to either an egg fertilized by a sperm, or an egg which has had somatic cell nuclear material (DNA) transferred to it and duplication stimulated, are those from conservative religious traditions, both Roman Catholic and Protestant. • Yet they do not appear to have biblical, theological or ecclesiastical support for their position.
Religious Issues in Defining a Person • Thomas Aquinas, the pre-eminent Roman Catholic theologian of the 13th century, held that the embryo did not have a soul (become a person) until it took on the substantive appearance of a human being—this is somewhere around the 12th week of pregnancy. • This view was endorsed by the Roman Catholic Church at the Council of Vienne in 1312 and has been the official position of that church ever since, having never been repudiated.
Religious Issues in Defining a Person • Frequently, we see on billboards a biblical passage from Jeremiah placed there by those opposed to abortion: “Before I formed you in the womb I knew you, and before you were born I consecrated you.” • In what proceeds this passage and what follows, it is clear that Jeremiah is discussing nothing to do with human personhood, the sanctity of life or abortion. • Rather, Jeremiah is merely pointing out that it was God’s intention from before he was born that Jeremiah would be his prophet. • A God with foreknowledge can do that!
Religious Issues in Defining a Person • In the 21st chapter of Exodus, a specific judgment is made about the status of the zygote, embryo, and/or fetus. • There the Hebrew Scriptures state that the penalty for murder is to be death. • However, it is also said that if a pregnant woman is caused to have a miscarriage by the actions of another, the penalty is only to be a fine paid to her husband. • Murder was not a category that included the contents of the uterus. • The conclusion being able to be drawn that such was not considered by the God of the Hebrews to be a person.
Religious Issues in Defining a Person • Probably the most relevant passage in the Judeo-Christian literature regarding personhood is in Genesis 2:7:“and (God) breathed into him (speaking of Adam) the breath of life, and man became a living soul.” • God’s breath gave man his soul. The word soul has its etymological roots in the Indo-European root bhs, from which is derived the verb “to blow.” Soul originally meant breath, the breath of life. Thus in terms of etymological development, the soul was understood to be in the breath. • This simply confirms the statement of Genesis 2:7. • Life, the soul, is in the breath; the breath breathed by the infant at birth. • Judeo-Christian scriptures indicate that a person becomes a person at the time most people have always thought one becomes a person . . . at birth.
Summary and Conclusions Regarding Personhood . . .from Biology, Philosophy and Religion • Biology informs us that subsequent to fertilization the majority of fertilized eggs do not survive, and that subsequent to conception (pregnancy), a significant number of embryos and fetuses are spontaneously aborted. If these cells/tissues are persons then there are serious social, legal, and even religious matters opened that must be addressed. • Philosophically, careful distinctions are drawn among several conceptualizations of being a person: biologic, psycho-social, and moral. None would permit the designation “person” to an entity that was not able to physiologically survive outside the uterus. • There is no firm theological, biblical, or ecclesiastical tradition or position within the Religious community (Roman Catholic or otherwise) as to when the resultant of fertilization becomes a person. In fact, Judeo-Christian scriptures seem to point to birth as being the point of ensoulment,and therefore personhood. • I liked Ernesto Scorscone’s comment in the General Assembly two years ago when he said, “The notion that a human being begins at fertilization, I think, defies science, it defies medicine, it defies logic, and I think it is bad public policy.” • I think he is right!
Challenging Errors in Thinking About Cloning Error One Cloning for scientific research and cures, therapeutic cloning, sends humanity hurtling down the slippery slope toward the inevitable cloning of human beings, reproductive cloning. • The best rebuttal to this argument are the thousands of failed attempts to clone animals. Cloning has a terrible track record in making embryos that develop into fetuses, let alone making it to birth. • Attempts to clone cows have failed 85% of the time; while more than one--third of those clones born alive suffer serious life-threatening health problems. • Despite much effort, no one has ever cloned a monkey or any other primate. Many experts believe primates or humans will never be cloned because primate biology is different that of other mammals.
Challenging Errors in Thinking About Cloning Error Two The pursuit of therapeutic cloning will lead to the exploitation of women for their eggs, since billions of eggs will be needed. • The number of eggs needed is grossly exaggerated. To move forward, cloned embryonic stem cell research would need thousands of eggs, not billions. The average woman produces 600,000 eggs during her lifetime. • Women are already providing thousands of eggs to infertile couples, and more women would want to donate these reproductive cells to help scientists find cures to diseases or disabilities, including a disease or disability they might have.
Challenging Errors in Thinking About Cloning Error Three What if someday scientists find a way to clone humans safely? • Genes influence behavior, but do not determine personality or behavior. Rather, each human is shaped by specific intrauterine influences, and by the unique time, place, environment, culture, and circumstances in which they live. • To create identically behaving individuals you would need more than their genes, you would need their mothers, fathers, and the environment and culture in which they grew up. • If human reproductive cloning ever worked—which is highly improbable on a mass scale—it would not bring back the dead, create a new pathway to immortality, or permit one to design a perfect replicate of one’s self.
Challenging Errors in Thinking About Cloning Error Four There are other techniques for finding cures including the use of adult stem cells so there is no need for cloning. • The reason to clone zygotes is that the resulting cells and tissues that are created would have the same genetic makeup as the person from which they came. Therefore, they could be transplanted back into the person with no fear of rejection. • Adult stem cells do not offer an equally valuable alternative because stem cells are the only cells capable of being transformed into all the various types of cells that make up the human body. All types of cells are necessary to fight disease and disability. No one has figured out a way to get adult stem cells to revert to this omni-potential state.
Ethics and Cloning . . .The Bottom Line • Therapeutic cloning, that is cloning for cures, has the potential to do enormous good by saving the lives of millions of people and ending agony for millions more. • These human beings and their loved ones, which one day may, if not now, include us, aren’t interested in pieties and abstractions and science fiction. They are desperately seeking help for their ailments and they need to have biomedical scientists free to pursue answers and cures. • Not only is human cloning ethical, banning all human cloning would be a highly unethical thing to do.
