Ethics of cloning

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In bioethics, the ethics of cloning concerns the ethical positions on the practice and possibilities of cloning, especially of humans. While many of these views are religious in origin, some of the questions raised are faced by secular perspectives as well. Perspectives on human cloning are theoretical, as human therapeutic and reproductive cloning are not commercially used; animals are currently cloned in laboratories and in livestock production.

Contents

Advocates support the development of therapeutic cloning in order to generate tissues and whole organs to treat patients who otherwise cannot obtain transplants, to avoid the need for immunosuppressive drugs, and to stave off the effects of aging. Advocates for reproductive cloning believe that parents who cannot otherwise procreate should have access to technology.

Opponents of cloning have concerns that technology is not yet developed enough to be safe, and that it could be prone to abuse, either in the form of clones raised as slaves, or leading to the generation of humans from whom organs and tissues would be harvested. Opponents have also raised concerns about how cloned individuals could integrate with families and with society at large.

Religious groups are divided, with some opposing the technology as usurping God's place and, to the extent embryo are used, destroying a human life; others support therapeutic cloning's potential life-saving benefits.

Cloning of animals is opposed by animal-groups due to the number of cloned animals that suffer from malformations before they die, and while meat of cloned animals has been approved by the US FDA, its use is opposed by some other groups concerned about food safety.

Philosophical debate

The various forms of cloning, particularly human cloning, are controversial. [1] There have been numerous demands for all progress in the human cloning field to be halted. Most scientific, governmental and religious organizations oppose reproductive cloning. The American Association for the Advancement of Science (AAAS) and other scientific organizations have made public statements suggesting that human reproductive cloning be banned until safety issues are resolved. [2] Serious ethical concerns have been raised by the future possibility of harvesting organs from clones. [3]

Advocates of human therapeutic cloning believe the practice could provide genetically identical cells for regenerative medicine, and tissues and organs for transplantation. [4] Such cells, tissues, and organs would neither trigger an immune response nor require the use of immunosuppressive drugs. Both basic research and therapeutic development for serious diseases such as cancer, heart disease, and diabetes, as well as improvements in burn treatment and reconstructive and cosmetic surgery, are areas that might benefit from such new technology. [5] One bioethicist, Jacob M. Appel of New York University, has gone so far as to argue that "children cloned for therapeutic purposes" such as "to donate bone marrow to a sibling with leukemia" may someday be viewed as heroes. [6] [7]

Proponents claim that human reproductive cloning also would produce benefits to couples who cannot otherwise procreate. In the early 2000s Severino Antinori and Panos Zavos stirred controversy when they publicly stated plans to create a fertility treatment that allows parents who are both infertile to have children with at least some of their DNA in their offspring. [8]

In Aubrey de Grey's proposed SENS (Strategies for Engineered Negligible Senescence), one of the considered options to repair the cell depletion related to cellular senescence is to grow replacement tissues from stem cells harvested from a cloned embryo. [9]

There are also ethical objections. Article 11 of UNESCO's Universal Declaration on the Human Genome and Human Rights asserts that the reproductive cloning of human beings is contrary to human dignity, [10] that a potential life represented by the embryo is destroyed when embryonic cells are used, [11] and there is a significant likelihood that cloned individuals would be biologically damaged, due to the inherent unreliability of cloning technology. [12]

Ethicists have speculated on difficulties that might arise in a world where human clones exist. For example, human cloning might change the shape of family structure by complicating the role of parenting within a family of convoluted kinship relations. For example, a female DNA donor would be the clone's genetic twin, rather than mother, complicating the genetic and social relationships between mother and child as well as the relationships between other family members and the clone. [13] In another example, there may be expectations that the cloned individuals would act identically to the human from which they were cloned, which could infringe on the right to self-determination. [14]

Proponents of animal rights argue that non-human animals possess certain moral rights as living entities and should therefore be afforded the same ethical considerations as human beings. This would negate the exploitation of animals in scientific research on cloning, cloning used in food production, or as other resources for human use or consumption. [15]

Religious views

Religious views of cloning are mixed. [16] [17]

Jainism and Hinduism

Hinduism views on cloning are very diverse. While some Hindu people view therapeutic cloning as necessary to fix childlessness, others believe it is immoral to tamper with nature. [18] The Sanatan Dharm (meaning the eternal set of duties for humans, which is what many people refer to Hinduism as) approves therapeutic cloning but does not approve human cloning. In Hinduism, one view has the creator, or the Brahman not as insecure to lay restrictions on scientific endeavours. Another view restricts human cloning. In Jainism, the birth of Mahavira is depicted as an operation of embryo transfer. [19]

In modern-day India, there have been clones of livestock species. Examples include Garima from the National Dairy Research Institute located in Karnal, where many other clones have been developed in Bovine species.[ citation needed ]

Judaism

Jewish view on cloning is unclear, but some orthodox rabbis allows cloning as a method of reproduction if no other method is available. Also Jewish religion treats all life equally even if it was formed by cloning. [20] Liberal Jewish groups oppose the cloning of humans. [21]

Christianity

Most of the Christian churches, including World council of Churches and United Methodist Church, oppose the research of cloning of either human embryos or whole human. [21] The Roman Catholic Church, under the papacy of Benedict XVI, condemned the practice of human cloning, in the magisterial instruction Dignitas Personae , stating that it represents a "grave offense to the dignity of that person as well as to the fundamental equality of all people." [22] Many conservative Christian groups have opposed human cloning and the cloning of human embryos, since they believe that life begins at the moment of conception. [23] Other Christian denominations such as the United Church of Christ do not believe a fertilized egg constitutes a living being, but still they oppose the cloning of embryonic cells.

Islam

There are different views when it comes to cloning in Islam, some scholars are of the view that human reproductive cloning is absolutely forbidden whilst others are of the view that there are some exceptions.

Animal cloning is allowed in Islam only if it bring benefits to all people and no harm is caused to the animal used in the cloning process. [21] [24]

Animal cloning

Cloned animals are used in medical research, pet cloning or for food. [25] [26]

Pet cloning

In 2005, an article in The Hastings Center Report said:

Critics of pet cloning typically offer three objections: (1) the cloning process causes animals to suffer; (2) widely available pet cloning could have bad consequences for the overwhelming numbers of unwanted companion animals; and, (3) companies that offer pet cloning are deceiving and exploiting grieving pet owners. [27]

Cloning animals for food

On December 28, 2006, the U.S. Food and Drug Administration (FDA) approved the consumption of meat and other products from cloned animals. [28] Cloned-animal products were said to be indistinguishable from the non-cloned animals. Furthermore, companies would not be required to provide labels informing the consumer that the meat comes from a cloned animal. In 2007, some meat and dairy producers did propose a system to track all cloned animals as they move through the food chain, suggesting that a national database system integrated into the National Animal Identification System could eventually allow food labeling. [29] [30] However, as of 2013 no tracking system exists, and products from cloned animals are sold for human consumption in the United States. [31] [32]

Critics have raised objections to the FDA's approval of cloned-animal products for human consumption, arguing that the FDA's research was inadequate, inappropriately limited, and of questionable scientific validity. [33] [34] Several consumer-advocate groups are working to encourage a tracking program that would allow consumers to become more aware of cloned-animal products within their food. [35]

A 2013 review noted that there is widespread misunderstanding about cloned and cattle, and found that cloned cattle that reached adulthood and entered the food supply were substantially equivalent to conventional cattle with respect to the quality of meat and milk, and with respect to their reproductive capability. [36]

In 2015, the European Union voted to ban the cloning of farm animals (cattle, pigs, sheep, goats, and horses), and the sale of cloned livestock, their offspring, and products derived from them, such as meat and milk. The ban excluded cloning for research, and for the conservation of rare breeds and endangered species. [37] [38] However, no law was passed after the vote. As of 2024, horse cloning continues to be legal in the EU, with the Zangersheide registry in Belgium offering three cloned stallions for breeding. [39]

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Related Research Articles

<span class="mw-page-title-main">Cloning</span> Process of producing individual organisms with identical genomes

Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of cells and of DNA fragments.

<span class="mw-page-title-main">Human cloning</span> Creation of a genetically identical copy of a human

Human cloning is the creation of a genetically identical copy of a human. The term is generally used to refer to artificial human cloning, which is the reproduction of human cells and tissue. It does not refer to the natural conception and delivery of identical twins. The possibilities of human cloning have raised controversies. These ethical concerns have prompted several nations to pass laws regarding human cloning.

<span class="mw-page-title-main">Embryo</span> Multicellular diploid eukaryote in its earliest stage of development

An embryo is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres are arranged as a solid ball that when reaching a certain size, called a morula, takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals.

<span class="mw-page-title-main">Clonaid</span> Human cloning organization

Clonaid is an American-based human cloning organization, registered as a company in the Bahamas. Founded in 1997, it has philosophical ties with the UFO religion Raëlism, which sees cloning as the first step in achieving immortality. On December 27, 2002, Clonaid's chief executive, Brigitte Boisselier, claimed that a baby clone, named Eve, was born. Media coverage of the claim sparked serious criticism and ethical debate that lasted more than a year. Florida attorney Bernard Siegel tried to appoint a special guardian for Eve and threatened to sue Clonaid, because he was afraid that the child might be treated like a lab rat. Siegel, who heard the company's actual name was not Clonaid, decided that the Clonaid project was a sham. Bioethicist Clara Alto condemned Clonaid for premature human experimentation and noted the high incidence of malformations and thousands of fetal deaths in animal cloning.

<span class="mw-page-title-main">Somatic cell nuclear transfer</span> Method of creating a cloned embryo by replacing the egg nucleus with a body cell nucleus

In genetics and developmental biology, somatic cell nuclear transfer (SCNT) is a laboratory strategy for creating a viable embryo from a body cell and an egg cell. The technique consists of taking a denucleated oocyte and implanting a donor nucleus from a somatic (body) cell. It is used in both therapeutic and reproductive cloning. In 1996, Dolly the sheep became famous for being the first successful case of the reproductive cloning of a mammal. In January 2018, a team of scientists in Shanghai announced the successful cloning of two female crab-eating macaques from foetal nuclei.

<span class="mw-page-title-main">Xenotransplantation</span> Transplantation of cells or tissue across species

Xenotransplantation, or heterologous transplant, is the transplantation of living cells, tissues or organs from one species to another. Such cells, tissues or organs are called xenografts or xenotransplants. It is contrasted with allotransplantation, syngeneic transplantation or isotransplantation and autotransplantation. Xenotransplantation is an artificial method of creating an animal-human chimera, that is, a human with a subset of animal cells. In contrast, an individual where each cell contains genetic material from a human and an animal is called a human–animal hybrid.

<span class="mw-page-title-main">Leon Kass</span> American academic (born 1939)

Leon Richard Kass is an American physician, scientist, educator, and public intellectual. Kass is best known as a proponent of liberal arts education via the "Great Books," as a critic of human cloning, life extension, euthanasia and embryo research, and for his tenure as chairman of the President's Council on Bioethics from 2001 to 2005. Although Kass is often referred to as a bioethicist, he eschews the term and refers to himself as "an old-fashioned humanist. A humanist is concerned broadly with all aspects of human life, not just the ethical."

<span class="mw-page-title-main">Embryonic stem cell</span> Type of pluripotent blastocystic stem cell

Embryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre-implantation embryo. Human embryos reach the blastocyst stage 4–5 days post fertilization, at which time they consist of 50–150 cells. Isolating the inner cell mass (embryoblast) using immunosurgery results in destruction of the blastocyst, a process which raises ethical issues, including whether or not embryos at the pre-implantation stage have the same moral considerations as embryos in the post-implantation stage of development.

Commercial animal cloning is the cloning of animals for commercial purposes, including animal husbandry, medical research, competition camels and horses, pet cloning, and restoring populations of endangered and extinct animals. The practice was first demonstrated in 1996 with Dolly the sheep.

<span class="mw-page-title-main">Designer baby</span> Genetically modified human embryo

A designer baby is a baby whose genetic makeup has been selected or altered, often to exclude a particular gene or to remove genes associated with disease. This process usually involves analysing a wide range of human embryos to identify genes associated with particular diseases and characteristics, and selecting embryos that have the desired genetic makeup; a process known as preimplantation genetic diagnosis. Screening for single genes is commonly practiced, and polygenic screening is offered by a few companies. Other methods by which a baby's genetic information can be altered involve directly editing the genome before birth, which is not routinely performed and only one instance of this is known to have occurred as of 2019, where Chinese twins Lulu and Nana were edited as embryos, causing widespread criticism.

Christians take multiple positions in the debate on the morality of human cloning. Since Dolly the sheep was successfully cloned on 5 July 1996, and the possibility of cloning humans became a reality, Christian leaders have been pressed to take an ethical stance on its morality. While many Christians tend to disagree with the practice, such as Roman Catholics and a majority of fundamentalist pastors, including Southern Baptists, the views taken by various other Christian denominations are diverse and often conflicting. It is hard to pinpoint any one, definite stance of the Christian religion, since there are so many Christian denominations and so few official statements from each of them concerning the morality of human cloning.

<span class="mw-page-title-main">Axel Kahn</span> French geneticist (1944–2021)

Axel Kahn was a French geneticist. He was the brother of the journalist Jean-François Kahn and the chemist Olivier Kahn. He was a member of the French National Consultative Ethics Committee from 1992 to 2004 and worked in gene therapy. He first entered the INSERM with a specialization in biochemistry. He was named in 2002 as a counsellor for biosciences and biotechnologies matters by the European Commission. Head of French laboratories specialized in biomedical sciences between years 1984 and 2007, he was elected President of the Paris Descartes University in December 2007, as the sole candidate.

<span class="mw-page-title-main">Stem cell controversy</span> Ethical concerns about embryonic stem cell research and medical use

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Stem cell laws are the law rules, and policy governance concerning the sources, research, and uses in treatment of stem cells in humans. These laws have been the source of much controversy and vary significantly by country. In the European Union, stem cell research using the human embryo is permitted in Sweden, Spain, Finland, Belgium, Greece, Britain, Denmark and the Netherlands; however, it is illegal in Germany, Austria, Ireland, Italy, and Portugal. The issue has similarly divided the United States, with several states enforcing a complete ban and others giving support. Elsewhere, Japan, India, Iran, Israel, South Korea, China, and Australia are supportive. However, New Zealand, most of Africa, and most of South America are restrictive.

Stem cell laws and policy in the United States have had a complicated legal and political history.

Mitochondrial replacement therapy (MRT), sometimes called mitochondrial donation, is the replacement of mitochondria in one or more cells to prevent or ameliorate disease. MRT originated as a special form of in vitro fertilisation in which some or all of the future baby's mitochondrial DNA (mtDNA) comes from a third party. This technique is used in cases when mothers carry genes for mitochondrial diseases. The therapy is approved for use in the United Kingdom. A second application is to use autologous mitochondria to replace mitochondria in damaged tissue to restore the tissue to a functional state. This has been used in clinical research in the United States to treat cardiac-compromised newborns.

Jan Deckers works in bioethics at Newcastle University. His work revolves mainly around three topics: animal ethics, reproductive ethics and embryo research, and ethics of genetics.

Human germline engineering is the process by which the genome of an individual is edited in such a way that the change is heritable. This is achieved by altering the genes of the germ cells, which then mature into genetically modified eggs and sperm. For safety, ethical, and social reasons, there is broad agreement among the scientific community and the public that germline editing for reproduction is a red line that should not be crossed at this point in time. There are differing public sentiments, however, on whether it may be performed in the future depending on whether the intent would be therapeutic or non-therapeutic.

<span class="mw-page-title-main">He Jiankui affair</span> 2018 scientific and bioethical controversy

The He Jiankui affair is a scientific and bioethical controversy concerning the use of genome editing following its first use on humans by Chinese scientist He Jiankui, who edited the genomes of human embryos in 2018. He became widely known on 26 November 2018 after he announced that he had created the first human genetically edited babies. He was listed in Time magazine's 100 most influential people of 2019. The affair led to ethical and legal controversies, resulting in the indictment of He and two of his collaborators, Zhang Renli and Qin Jinzhou. He eventually received widespread international condemnation.

<span class="mw-page-title-main">Hwang affair</span> South Korean scientific misconduct scandal

The Hwang affair, or Hwang scandal, or Hwanggate, is a case of scientific misconduct and ethical issues surrounding a South Korean biologist, Hwang Woo-suk, who claimed to have created the first human embryonic stem cells by cloning in 2004. Hwang and his research team at the Seoul National University reported in the journal Science that they successfully developed a somatic cell nuclear transfer method with which they made the stem cells. In 2005, they published again in Science the successful cloning of 11 person-specific stem cells using 185 human eggs. The research was hailed as "a ground-breaking paper" in science. Hwang was elevated as "the pride of Korea", "national hero" [of Korea], and a "supreme scientist", to international praise and fame. Recognitions and honours immediately followed, including South Korea's Presidential Award in Science and Technology, and Time magazine listing him among the "People Who Mattered 2004" and the most influential people "The 2004 Time 100".

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