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Ethical Issues on Animal and Human cloning

Ethical Issues on Animal and Human cloning. Prof. P.C. Shaw ( 邵鵬柱教授) Department of Biochemistry, CUHK Hong Kong Bioethics Association November 2009. 複 製 人 ?. History of cloning. 1952 N orthern leopard frogs cloned . 1953 S tructure of DNA discovered . History of cloning.

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Ethical Issues on Animal and Human cloning

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  1. Ethical Issues on Animal and Human cloning Prof. P.C. Shaw (邵鵬柱教授) Department of Biochemistry, CUHK Hong Kong Bioethics Association November 2009

  2. 複 製 人 ?

  3. History of cloning • 1952 Northern leopard frogs cloned. • 1953 Structure of DNA discovered.

  4. History of cloning • 1978 Louise, the first child conceived through in vitro fertilization, was born. • 1993 Human embryos were first cloned (artificial embryo twinning) • July 5, 1996Dolly was born. Photo from: www.cnn.com

  5. Dolly – the first mammal cloned using mature cell • Dolly the Lamb in 1996 • Method: Nuclear transfer • Organization: Roslin Institute at UK and PPL Therapeutics Photo from Ming Pao 18th August 2002

  6. Example of cloning • Cumulina the Mouse in 1998 • Organization: University of Hawaii Photo from Ming Pao 28th December 2002

  7. Example of cloning • Cattle in 1998 • Organization: Kinki University at Japan Photo from Ming Pao 28th December 2002

  8. Example of cloning • Mille, Christa, Alexis, Carrel and Dotcom the Pigs in 2000 • Organization: PPL Therapeutics of UK Photo from Ming Pao 28th December 2002

  9. Example of cloning • Carbon Copy the Cat in 2002 • Organization: Texas A & M University, USA Photo from Ming Pao 23th January 2003

  10. Example of cloning • Generation of Prometea, 2003 • Organization: A research laboratory in Italy Photo from Nature No.6949

  11. Examples of cloning • Cloning of donkey, 2004, USA • Cloning of dog, 2005, Korea • Cloning of rhesus monkey, 2007, Oregon, USA http://jamaica-gleaner.com/gleaner/20050806/mind/mind3.html http://www.pbs.org/newshour/bb/science/july-dec07/stemcells_11-15.html

  12. Two methods of cloning • Embryo cloning 胚胎複製- remove a cell from an embryo for developing into a separate embryo. • Adult cell cloning 成長細胞複製-replace DNA/nucleus from a cell by another.

  13. Two methods of cloning • Embryo cloning 胚胎複製– do not know the characteristics of the offspring. • Adult cell cloning 成長細胞複製–characteristics are almost the same as the nucleus donor.

  14. How to generate Dolly? Step 1. Udder (乳腺)cells were taken from a donor sheep. Cells were then cultured to switch off their genes and become dormant. Photo from www.bootstrike.com, www.nature.com

  15. How to generate Dolly? Step 2. Unfertilized egg cell was taken from another sheep. The nucleus was removed, leaving an empty egg. Photo from www.pbs.org. www.nature.com, www.sciam.com

  16. How to generate Dolly? Step 3. The egg cell without nucleus was fused with the donor cell using a pulse of electricity. A second pulse started the cell division. Photo from www.advancedcell.com. www.nature.com

  17. How to generate Dolly? Step 4. After 6 days, the resulting embryo was implanted into another sheep (surrogate mother代母). Photo from www.pbs.org, www.nature.com

  18. How to generate Dolly? Step 5. After gestation (妊娠), the surrogate mother gave birth to Dolly whichwas identical to the udder cell donor. Photo from www.pbs.org

  19. Advantages of animal cloning • Can produce animal with a desired trait, for • Protein products, organs • Proliferate endangered animals

  20. Cloning of endangered animal • Noah the Gaur (亞洲野牛, an endangered species) in 2000 • Organization: Advanced Cell Technology, USA Photo from Advanced Cell Technology (www.advancedcell.com)

  21. Cloning of endangered animal • Cloning of woolly Mammoth (長毛象) • Extinct 10,000 years ago • Is there any intact cell left? From Mingpao 8/8/2003

  22. Cloning of transgenic animal • Cloning of a cow containing mad cow disease resistant gene • In Shangdong, China From Mingpao 28/4/2006

  23. Concerns in animal cloning • Technology complicated • Survival rate of cloned embryos low • Overweighing of calves at birth • Breeders may want to keep their animal unique • Breeders may want to create better offspring

  24. Health of clones From Ming Pao 27-Mar-2001 • Poor development of heart, lung and immune system • Might have genetic disorder

  25. Dolly gave birth to a female lamb in 1998, but Dolly later died of premature aging in 2003. Photo from Mingpao

  26. Company for cloning pets • Genetic Savings & Clone – established in 2000, produced the cloned cat, CC in 2001 • Delivered the first commercially cloned cat, Little Nicky in 2004 for US$50,000 • Company closed in 2006 • A new company BioArts International was established for cloning dogs

  27. Commercial pet cloning may not be a good investment • Demand not high • Competition from developing countries • Disregard of the IP issues • Relaxed treatment of animals • The IP holder does not want to defense the IP rights • Outcome is unpredicted – cloning is not a mature techniques • Pressure from the society

  28. Cloning Human

  29. Cloning – two kinds • Reproductive cloning – an embryo is created and implanted into a woman’s womb to bring it to term. • Therapeutic cloning – an embryo is created in order to obtain cells from it.

  30. Why clone human? • Just an ‘unconventional’ means of reproduction • In vitro fertilization • Surrogate mother • Adoption

  31. Why clone human? • Study human development • Produce spare parts • Test for genetic defect • Increase chance of pregnancy • Produce two children at the same time

  32. Why clone human? • Preserve traits and talents • Extension of life in unusual circumstances • One spouse sterile • Homosexual marriage

  33. Positive points of therapeutic cloning • Cloned embryos provide : • Brain cells for disorders like Parkinson (柏金遜) and Alzheimer’s disease (老年痴呆症) • Pancreatic islet cells for diabetes (糖尿)

  34. Positive points of therapeutic cloning • Cloned embryos provide : • Nerve cells for spinal cord damage (脊椎受損) • Blood and bone marrow cells for blood cell disorder (血液疾病)

  35. The use of stem cells to generate clones Embryonic stem cells Adult stem cells http://dels.nas.edu/bls/stemcells/types-of-stem-cells.shtml

  36. Creating an embryo through in vitro fertilization, • culturing ES cells derived from it to provide a sufficient population for the tricky task of inserting genes • extracting the nucleus of a successfully altered cell to construct a cloned embryo • The resulting offspring would have developed from a cell derived from an embryo created with an egg and a sperm, and "improved" in the laboratory. http://www.geneticsandsociety.org/article.php?id=257

  37. Why not perform reproductive cloning? • Eugenic (優生) – to maximize certain traits intentionally • Reduce genetic diversity • Use as substitute for organ • Clone may have reduced life expectancy • Clone may be abnormal

  38. Why not perform reproductive cloning? • Lack of self-identity • Replaceable • Dominated by the ‘father’ or ‘mother’

  39. Why not perform reproductive cloning? • Upset traditional family relationship • Twin of the cell donor? • Relationship with its brother and sister • Relationship with spouse of the cell donor

  40. Human Reproductive Technology Bill香港人類生殖科技條例 (2000) • Not allow the followings: • Replace nucleus of an embryo with nucleus of another cell • Clone an embryo • Trading of embryo

  41. Human cloning in China • 人类辅助生殖技术与人类精子库相关技术规范、基本标准和伦理原则(Oct. 1, 2003) – by Ministry of Health • Prohibits surrogate mother • Prohibits reproductive human cloning • Prohibits donation of embryos • Prohibits trading of eggs

  42. 雷爾教派倡導複製人研究。 CLONAID™ was founded in February 1997, by Raël, the leader of the Raelian Movement, an international religious organization, which claims that a human extraterrestrial race, called the Elohim, used DNA and genetic engineering, to scientifically create all life on Earth. Adapted from Clonaid.com

  43. Recent Development in Human Cloning • Clonaid claimed to give birth to ‘Eve’ on 26 December 2002 • announced a second birth to a Dutch lesbian woman early in January 2003 and a third to a Japanese couple who "cloned their dead son killed in an accident", plus two others in late January

  44. Recent Development in Human Cloning • Korean Scientists led by Dr. Woo-suk Hwangproduced cloned human embryos (Science,Feb. 12, 2004) – later found to be fabricated • American scientist Panayiotis Zavos claimed to have cloned 14 human embryos and transferred 11 of them into the wombs of four women (April, 2009)

  45. Recent Development in Human Cloning • August 2004 - UK granted the first licence for work toward therapeutic cloning. • Nov. 2004 - Californians passed a $3 billion measure to create an Institute for Regenerative Medicine based on embryonic stem cell research.

  46. Please consider ...... • Would the views of animal and human cloning differ among people with different religious believes? • Is embryo a living human? • Since the use of stem cells for therapeutic cloning is still in experimental stage, would the use of cells from embryo be acceptable? • How about using the embryos left over after in vitro fertilization?

  47. Please consider ...... • Is reproductive cloning a violation of natural birth? • How about the cloning of a beloved one who dies accidentally? • How about cloning for sterile couples? • Under what circumstances do you want to make a copy of yourself?

  48. End

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