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Outline

Human Cloning

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"Cloning is unsafe for the..." Cloning is unsafe for the clone and surrogate mother The numbers are against survival Dolly the sheep, first cloned mammal:  1 live birth out of 277 cloned embryos (0.4%) Cloned mice:  5 live births out of 613 cloned embryos (0.8%)   5 live births out of 314 cloned embryos implanted (1.6%) (0.3%; 1 survived)   26 live births out of 312 cloned embryos implanted (8.3%) (4.2%; 13 survived) Cloned pigs:  5 live births out of 72 cloned embryos implanted (7%) Cloned goats:  3 live births out of 85 cloned embryos implanted (3.5%) Cloned cattle:  30 live births out of 496 cloned embryos implanted (6%) (4.8%; 24 survived) Cloned cat:  1 live birth out of 188 cloned embryos (0.5%);  of 87 embryos implanted (1.1%) Cloned gaur: 1 live birth out of 692 cloned embryos (81 blastocysts) (0.1%) (0%; 0 survived) Cloned rabbits: 6 live births out of 1852 cloned embryos (0.3%) (0.2%; 4 survived) Cloned banteng: 2 live births out of 30 cloned embryos implanted (6.7%) (3.3%; 1 survived) Cloned mule (fetal cells): 3 live births out of 334 cloned embryos (0.9%) Cloned horse: 1 live birth out of 841 cloned embryos (0.1%) Cloned rats:  3 live births out of 129 cloned embryos implanted (2.3%) (1.6%; 2 survived) Even apparently healthy clones have gene expression abnormalities. *Humpherys D et al.; “Epigenetic instability in ES cells and cloned mice”; Science 293, 95-97; 6 July 2001 *Humpherys D et al.; “Abnormal gene expression in cloned mice derived from embryonic stem cell and cumulus cell nuclei”; Proc. Natl. Acad. Sci. USA 99, 12889-12894; 1 October 2002 A review of all the world’s cloned animals suggests that every one of them is defective. Ian Wilmut: “There is abundant evidence that cloning can and does go wrong and no justification for believing that this will not happen with humans.” “Gene defects emerge in all animal clones”, Sunday Times of London, April 28, 2002 Health risk for the surrogate mother—“large offspring syndrome”

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"Promises," Promises, Premises, and Published Data… Claims unsubstantiated for embryonic stem cells Current or potential embryonic stem cell problems: Difficult to establish and maintain Difficulty in obtaining pure cultures in the dish Questions regarding functional differentiation Sipione S et al., “Insulin expressing cells from differentiated embryonic stem cells are not beta cells”, Diabetologia published online 14 Feb 2004; doi:10.1007/s00125-004-1349-z Rajagopal J et al.; “Insulin staining of ES cell progeny from insulin uptake”; Science  299, 363; 17 Jan 2003 Zhang YM et al.; “Stem cell-derived cardiomyocytes demonstrate arrhythmic potential”; Circulation 106, 1294-1299; 3 September 2002 Problem of immune rejection Potential for tumor formation and tissue destruction Wakitani S et al.; “Embryonic stem cells injected into the mouse knee joint form teratomas and subsequently destroy the joint”; Rheumatology 42, 162-165; January 2003 Genomic instability Cowan CA et al., “Derivation of embryonic stem-cell lines from human blastocysts”, New England Journal of Medicine 350, 13; published online 3 March 2004 Draper JS et al., “Recurrent gain of chromosomes 17q and 12 in cultured human embryonic stem cells”, Nature Biotechnology 22, 53-54; January 2004 Humpherys S et al.; “Epigenetic instability in ES cells and cloned mice”; Science 293, 95-97; 6 July  2001 Few and modest successes in animals, no clinical treatments Ethically contentious

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"Current Clinical Uses of Adult..." Current Clinical Uses of Adult Stem Cells Cancers—Lymphomas, multiple myeloma, leukemias, breast cancer, neuroblastoma, renal cell carcinoma, ovarian cancer Autoimmune diseases—multiple sclerosis, systemic lupus, rheumatoid arthritis, scleroderma, scleromyxedema, Crohn’s disease Anemias (incl. sickle cell anemia) Immunodeficiencies—including human gene therapy Bone/cartilage deformities—children with osteogenesis imperfecta Corneal scarring-generation of new corneas to restore sight Stroke—neural cell implants in clinical trials Repairing cardiac tissue after heart attack—bone marrow or muscle stem cells from patient Parkinson’s—retinal stem cells,patient’s own neural stem cells, injected growth factors Growth of new blood vessels—e.g., preventing gangrene Gastrointestinal epithelia—regenerate damaged ulcerous tissue Skin—grafts grown from hair follicle stem cells, after plucking a few hairs from patient Wound healing—bone marrow stem cells stimulated skin healing Spinal cord injury—clinical trials currently in Portugal, Italy, Israel, U.S.

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"Arguments Against Human Cloning" Arguments Against Human Cloning No evidence that cloning is necessary or useful for medical treatments Cloning research will divert resources and delay cures Banning only implantation is unenforceable Possible reproduction of living or deceased persons without knowledge or consent Confusion—kinship, parent-child identity, parental expectations Creates a class of humans who exist only as a means to achieve the ends of others Risking health and exploitation of women Leading to commodification, commercialization of human life Gateway to genetic manipulation and control of human beings Unsafe, Unethical, Unnecessary

"What does it mean to..." What does it mean to be human? Person or property? To whom do we choose to assign value? Who will benefit?  Who will decide?