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Animal and human cloning

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Mohammed Ibrahim

Therapeutic and reproductive cloning are two types of human cloning. Therapeutic cloning involves cloning cells for medical use and research, while reproductive cloning aims to clone an entire human. The history of human cloning began in the 1960s and major milestones include Dolly the sheep in 1996 and the first human stem cells from cloning in 2013. Methods like somatic cell nuclear transfer (SCNT) remove the nucleus of an egg and replace it with the nucleus of a donor cell. While cloning holds promise for regenerative medicine, it also raises ethical issues around the moral status of embryos and mental/physical risks of cloning humans.

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Animal and human cloning
Animal and Human CloningAnimal and Human Cloning
Objectives:
Definition Clone derived from Greek word Koln(twig) that is process of creating identical. Human cloning is the creation of a genetically identical copy of a human. It does not refer to the natural conception and delivery of identical twins.
History scientists and policy makers began to take the prospect seriously in the 1960s. 1966:Joshua Lederberg)Nobel Prize-winning geneticist)advocated cloning and genetic engineering in an article in The American Naturalist and inThe Washington Post. 1971:He sparked a debate with conservative bioethicist Leon Kass, who wrote at the time that "the programmed reproduction of man will, in fact, dehumanize him.“ James D. Watson, publicized the potential and the perils of cloning in his Atlantic Monthly essay, "Moving Toward the Clonal Man“. 1996:cloning of a sheep known as Dolly by somatic cell nuclear transfer (SCNT(. 1998:The first hybrid human clone was created by Advanced Cell Technology. It was created using SCNT - a nucleus was taken from a man's leg cell and inserted into a cow's egg from which the nucleus had been removed, and the hybrid cell was cultured, and developed into an embryo. The embryo was destroyed after 12 days.
History 2004,2005:-Hwang Woo suk,a professor at Seoul National University , published two separate articles in the journal Science claiming to have successfully harvested pluripotent, embryonic stem cells from a cloned human blastocyst using somatic-cell nuclear transfer techniques. Hwang claimed to have created eleven different patent- specific stem cell lines. This would have been the first major breakthrough in human cloning.However, in 2006 Science retracted both of his articles on clear evidence that much of his data from the experiments was fabricated. 2008:Dr. Andrew French and Samuel Wood of the biotechnology company Stemagen announced that they successfully created the first five mature human embryos using SCNT. The embyros were developed only to the blastocyst stage, at which point they were studied in processes that destroyed them. 2011:scientists at the New York Stem Cell Foundation announced that they had succeeded in generating embyronic stem cell lines, but their process involved leaving the oocyte's nucleus in place, resulting in triploid cells, which would not be useful for cloning.
History 2013:a group of scientists led by Shoukhrat Mitalipov published the first report of embryonic stem cells created using SCNT. In this experiment, the researchers developed a protocol for using SCNT in human cells, which differs slightly from the one used in other organisms. Four embryonic stem cell lines from human fetal somatic cells were derived from those blastocysts. All four lines were derived using oocytes from the same donor, ensuring that all mitochondrial DNA inherited was identical. 2014:a team led by Robert Lanza at Advanced Cell Technology reported that they had replicated Mitalipov's results and further demonstrated the effectiveness by cloning adult cells using SCNT.
Types 1-Therapeutic Cloning: involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014. Two common methods of therapeutic cloning are: .Somatic cell nuclear transfer (SCNT( .Induced pluripotent stem cells (iPSCs( 2-Reproductive Cloning: involve making an entire cloned human, instead of just specific cells or tissues.
Animal and human cloning
1-Somatic cell nuclear transfer (SCNT( .The nucleus of a somatic cell is taken from a donor and transplanted into a host egg cell by micropipette, which had its own genetic material removed previously, making it an enucleated egg. .The somatic cell genetic material is fused with the egg using an electric current. .Once the two cells have fused, the new cell can be permitted to grow in a surrogate or artificially.
2-The Roslin Technique The nucleus of an egg cell is removed (enucleated(. The enucleated egg cell and a somatic cell are joined together by an electrical charge and implanted into the host organism (in the case of Dolly, it was a sheep(. The cell should act like a normal egg and grow into a new organism, as a clone of the donor animal.
3-The Honolulu Technique The nucleus of a somatic cell is removed The nucleus of an egg cell is removed The Somatic cell’s nucleus is implanted into the cytoplasm of the egg cell The egg is then treated with special chemicals and implanted into the surrogate organism
Uses, Actual and Potential useful for research into the causes of disease, and as model systems used in drug discovery. used in stem cell therapy, or to create organs to be used in transplantation, known as regenerative medicine. Research is underway to potentially use stem cell therapy to treat heart disease, diabetes, and spinal cord injuries. In current research, human pluripotent stem cells have been promised as a reliable source for generating human neurons, showing the potential for regenerative medicine in brain and neural injuries.
Animal and human cloning
Ethical Implications Therapeutic Cloning is the creation of an embryo to supply embryonic stem cells for medical use The creation of a human embryonic stem cell line requires the destruction of an embryo Some groups argue that embryos are not the equivalent of life, and only have the potential for life Other groups argue that an embryo is a living being that is killed for stem cells
Ethical Implications Although cloning animals has been somewhat successful, it is extremely expensive and inefficient Most cloning attempts result in a fail rate of over 90% and experiments that do succeed usually result in complications and premature death It is difficult to foresee how these complications would translate for human experiments In addition the mental impact of cloning must also be considered, while the mental conditions of animals rarely affect their development, the development of humans is extremely sensitive to mental instability
Ethical Implications Scientists have found ways to get around the ethical issues associated with Embryonic Stem Cells Pluripotency- the ability for a cell to differentiate into many different types of cells The Induced Pluripotent Stem Cell is a stem cell that is derived from a non-pluripotent cell such as a typical adult somatic cell, which has been changed into a stem cell by forced gene expression Because Induced Pluripotent Stem cells are derived from the somatic tissues of recipient patients, they overcome two major hurdles human embryonic stem cells have faced: immune rejection and the ethical concerns surrounding Embryonic Stem cells
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Animal and human cloning

  • 2. Animal and Human CloningAnimal and Human Cloning
  • 4. Definition Clone derived from Greek word Koln(twig) that is process of creating identical. Human cloning is the creation of a genetically identical copy of a human. It does not refer to the natural conception and delivery of identical twins.
  • 5. History scientists and policy makers began to take the prospect seriously in the 1960s. 1966:Joshua Lederberg)Nobel Prize-winning geneticist)advocated cloning and genetic engineering in an article in The American Naturalist and inThe Washington Post. 1971:He sparked a debate with conservative bioethicist Leon Kass, who wrote at the time that "the programmed reproduction of man will, in fact, dehumanize him.“ James D. Watson, publicized the potential and the perils of cloning in his Atlantic Monthly essay, "Moving Toward the Clonal Man“. 1996:cloning of a sheep known as Dolly by somatic cell nuclear transfer (SCNT(. 1998:The first hybrid human clone was created by Advanced Cell Technology. It was created using SCNT - a nucleus was taken from a man's leg cell and inserted into a cow's egg from which the nucleus had been removed, and the hybrid cell was cultured, and developed into an embryo. The embryo was destroyed after 12 days.
  • 6. History 2004,2005:-Hwang Woo suk,a professor at Seoul National University , published two separate articles in the journal Science claiming to have successfully harvested pluripotent, embryonic stem cells from a cloned human blastocyst using somatic-cell nuclear transfer techniques. Hwang claimed to have created eleven different patent- specific stem cell lines. This would have been the first major breakthrough in human cloning.However, in 2006 Science retracted both of his articles on clear evidence that much of his data from the experiments was fabricated. 2008:Dr. Andrew French and Samuel Wood of the biotechnology company Stemagen announced that they successfully created the first five mature human embryos using SCNT. The embyros were developed only to the blastocyst stage, at which point they were studied in processes that destroyed them. 2011:scientists at the New York Stem Cell Foundation announced that they had succeeded in generating embyronic stem cell lines, but their process involved leaving the oocyte's nucleus in place, resulting in triploid cells, which would not be useful for cloning.
  • 7. History 2013:a group of scientists led by Shoukhrat Mitalipov published the first report of embryonic stem cells created using SCNT. In this experiment, the researchers developed a protocol for using SCNT in human cells, which differs slightly from the one used in other organisms. Four embryonic stem cell lines from human fetal somatic cells were derived from those blastocysts. All four lines were derived using oocytes from the same donor, ensuring that all mitochondrial DNA inherited was identical. 2014:a team led by Robert Lanza at Advanced Cell Technology reported that they had replicated Mitalipov's results and further demonstrated the effectiveness by cloning adult cells using SCNT.
  • 8. Types 1-Therapeutic Cloning: involve cloning cells from a human for use in medicine and transplants, and is an active area of research, but is not in medical practice anywhere in the world, as of 2014. Two common methods of therapeutic cloning are: .Somatic cell nuclear transfer (SCNT( .Induced pluripotent stem cells (iPSCs( 2-Reproductive Cloning: involve making an entire cloned human, instead of just specific cells or tissues.
  • 10. 1-Somatic cell nuclear transfer (SCNT( .The nucleus of a somatic cell is taken from a donor and transplanted into a host egg cell by micropipette, which had its own genetic material removed previously, making it an enucleated egg. .The somatic cell genetic material is fused with the egg using an electric current. .Once the two cells have fused, the new cell can be permitted to grow in a surrogate or artificially.
  • 11. 2-The Roslin Technique The nucleus of an egg cell is removed (enucleated(. The enucleated egg cell and a somatic cell are joined together by an electrical charge and implanted into the host organism (in the case of Dolly, it was a sheep(. The cell should act like a normal egg and grow into a new organism, as a clone of the donor animal.
  • 12. 3-The Honolulu Technique The nucleus of a somatic cell is removed The nucleus of an egg cell is removed The Somatic cell’s nucleus is implanted into the cytoplasm of the egg cell The egg is then treated with special chemicals and implanted into the surrogate organism
  • 13. Uses, Actual and Potential useful for research into the causes of disease, and as model systems used in drug discovery. used in stem cell therapy, or to create organs to be used in transplantation, known as regenerative medicine. Research is underway to potentially use stem cell therapy to treat heart disease, diabetes, and spinal cord injuries. In current research, human pluripotent stem cells have been promised as a reliable source for generating human neurons, showing the potential for regenerative medicine in brain and neural injuries.
  • 15. Ethical Implications Therapeutic Cloning is the creation of an embryo to supply embryonic stem cells for medical use The creation of a human embryonic stem cell line requires the destruction of an embryo Some groups argue that embryos are not the equivalent of life, and only have the potential for life Other groups argue that an embryo is a living being that is killed for stem cells
  • 16. Ethical Implications Although cloning animals has been somewhat successful, it is extremely expensive and inefficient Most cloning attempts result in a fail rate of over 90% and experiments that do succeed usually result in complications and premature death It is difficult to foresee how these complications would translate for human experiments In addition the mental impact of cloning must also be considered, while the mental conditions of animals rarely affect their development, the development of humans is extremely sensitive to mental instability
  • 17. Ethical Implications Scientists have found ways to get around the ethical issues associated with Embryonic Stem Cells Pluripotency- the ability for a cell to differentiate into many different types of cells The Induced Pluripotent Stem Cell is a stem cell that is derived from a non-pluripotent cell such as a typical adult somatic cell, which has been changed into a stem cell by forced gene expression Because Induced Pluripotent Stem cells are derived from the somatic tissues of recipient patients, they overcome two major hurdles human embryonic stem cells have faced: immune rejection and the ethical concerns surrounding Embryonic Stem cells