精品英语：Ethical Issues on Animal and Human cloning课件.ppt

1、Ethical Issues on Animal and Human cloningProf.P.C.Shaw(邵鵬柱教授邵鵬柱教授)Department of Biochemistry,CUHKHong Kong Bioethics AssociationNovember 2009複製人?History of cloningn1952 Northern leopard frogs cloned.n1953 Structure of DNA discovered.History of cloningn1978 Louise,the first child conceived through i

2、n vitro fertilization,was born.n1993 Human embryos were first cloned(artificial embryo twinning)nJuly 5,1996Dolly was born.Photo from:Dolly the first mammal cloned using mature cellnDolly the Lamb in 1996nMethod:Nuclear transfer nOrganization:Roslin Institute at UK and PPL Therapeutics Photo from Mi

3、ng Pao 18th August 2002Example of cloningnCumulina the Mouse in 1998nOrganization:University of Hawaii Photo from Ming Pao 28th December 2002Example of cloningnCattle in 1998nOrganization:Kinki University at Japan Photo from Ming Pao 28th December 2002Example of cloningnMille,Christa,Alexis,Carrel a

4、nd Dotcom the Pigs in 2000nOrganization:PPL Therapeutics of UK Photo from Ming Pao 28th December 2002Example of cloningnCarbon Copy the Cat in 2002nOrganization:Texas A&M University,USA Photo from Ming Pao 23th January 2003Example of cloningnGeneration of Prometea,2003nOrganization:A research labora

5、tory in Italy Photo from Nature No.6949Examples of cloningnCloning of donkey,2004,USAnCloning of dog,2005,KoreanCloning of rhesus monkey,2007,Oregon,USA http:/jamaica- methods of cloningnEmbryo cloning 胚胎胚胎複製複製-remove a cell from an embryo for developing into a separate embryo.nAdult cell cloning 成長

6、細胞成長細胞複製複製-replace DNA/nucleus from a cell by another.Two methods of cloningnEmbryo cloning 胚胎胚胎複製複製 do not know the characteristics of the offspring.nAdult cell cloning 成長細胞成長細胞複製複製 characteristics are almost the same as the nucleus donor.How to generate Dolly?Step 1.Udder(乳腺)cells were taken from

7、a donor sheep.Cells were then cultured to switch off their genes and become dormant.Photo from , How to generate Dolly?Step 2.Unfertilized egg cell was taken from another sheep.The nucleus was removed,leaving an empty egg.Photo from , How to generate Dolly?Step 3.The egg cell without nucleus was fus

8、ed with the donor cell using a pulse of electricity.A second pulse started the cell division.Photo from 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,How to generate Dolly?Step 5.After gestation(妊娠),the sur

9、rogate mother gave birth to Dolly which was identical to the udder cell donor.Photo from www.pbs.orgAdvantages of animal cloningnCan produce animal with a desired trait,fornProtein products,organsnProliferate endangered animalsCloning of endangered animalnNoah the Gaur(亞洲野牛,an endangered species)in

10、2000nOrganization:Advanced Cell Technology,USAPhoto from Advanced Cell Technology()Cloning of endangered animalnCloning of woolly Mammoth(長毛象)nExtinct 10,000 years agonIs there any intact cell left?From Mingpao 8/8/2003Cloning of transgenic animalnCloning of a cow containing mad cow disease resistan

11、t genenIn Shangdong,ChinaFrom Mingpao 28/4/2006Concerns in animal cloningnTechnology complicated nSurvival rate of cloned embryos lownOverweighing of calves at birth nBreeders may want to keep their animal uniquenBreeders may want to create better offspringHealth of clonesFrom Ming Pao 27-Mar-2001 P

12、oor development of heart,lung and immune system Might have genetic disorderPhoto from MingpaoDolly gave birth to a female lamb in 1998,but Dolly later died of premature aging in 2003.Company for cloning petsnGenetic Savings&Clone established in 2000,produced the cloned cat,CC in 2001nDelivered the f

13、irst commercially cloned cat,Little Nicky in 2004 for US$50,000nCompany closed in 2006nA new company BioArts International was established for cloning dogs Commercial pet cloning may not be a good investmentnDemand not highnCompetition from developing countriesnDisregard of the IP issuesnRelaxed tre

14、atment of animalsnThe IP holder does not want to defense the IP rightsnOutcome is unpredicted cloning is not a mature techniquesnPressure from the societyCloning HumanCloning two kindsnReproductive cloning an embryo is created and implanted into a womans womb to bring it to term.nTherapeutic cloning

15、 an embryo is created in order to obtain cells from it.Why clone human?nJust an unconventional means of reproductionnIn vitro fertilizationnSurrogate mothernAdoptionnStudy human developmentnProduce spare partsnTest for genetic defectnIncrease chance of pregnancynProduce two children at the same time

16、Why clone human?nPreserve traits and talentsnExtension of life in unusual circumstancesnOne spouse sterilenHomosexual marriageWhy clone human?nCloned embryos provide:nBrain cells for disorders like Parkinson(柏金遜)and Alzheimers disease(老年痴呆症)nPancreatic islet cells for diabetes(糖尿)Positive points of

17、therapeutic cloningnCloned embryos provide:nNerve cells for spinal cord damage(脊椎受損)nBlood and bone marrow cells for blood cell disorder(血液疾病)Positive points of therapeutic cloninghttp:/dels.nas.edu/bls/stemcells/types-of-stem-cells.shtmlEmbryonic stem cellsAdult stem cellsThe use of stem cells to g

18、enerate cloneshttp:/www.geneticsandsociety.org/article.php?id=2571.Creating an embryo through in vitro fertilization,2.culturing ES cells derived from it to provide a sufficient population for the tricky task of inserting genes3.extracting the nucleus of a successfully altered cell to construct a cl

19、oned embryo4.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.Why not perform reproductive cloning?nEugenic(優生)to maximize certain traits intentionallynReduce genetic diversitynUse as substitute for organnC

20、lone may have reduced life expectancynClone may be abnormalWhy not perform reproductive cloning?nLack of self-identitynReplaceablenDominated by the father or motherWhy not perform reproductive cloning?nUpset traditional family relationshipnTwin of the cell donor?nRelationship with its brother and si

21、sternRelationship with spouse of the cell donorHuman Reproductive Technology Bill香港人類生殖科技條例(2000)nNot allow the followings:nReplace nucleus of an embryo with nucleus of another cellnClone an embryonTrading of embryoHuman cloning in Chinan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 Healt

22、hnProhibits surrogate mothernProhibits reproductive human cloningnProhibits donation of embryosnProhibits trading of eggs CLONAID was founded in February 1997,by Ral,the leader of the,an international religious organization,which claims that a human extraterrestrial race,called the,used DNA and gene

23、tic engineering,to scientifically create all life on Earth.Adapted from C雷爾教派倡導複製人研究。雷爾教派倡導複製人研究。Recent Development in Human CloningnClonaid claimed to give birth to Eve on 26 December 2002nannounced a second birth to a Dutch lesbian woman early in January 2003 and a third to a Japanese couple who c

24、loned their dead son killed in an accident,plus two others in late January Recent Development in Human CloningnKorean Scientists led by Dr.Woo-suk Hwang produced cloned human embryos(Science,Feb.12,2004)later found to be fabricatednAmerican scientist Panayiotis Zavos claimed to have cloned 14 human

25、embryos and transferred 11 of them into the wombs of four women(April,2009)Recent Development in Human CloningnAugust 2004-UK granted the first licence for work toward therapeutic cloning.nNov.2004-Californians passed a$3 billion measure to create an Institute for Regenerative Medicine based on embr

26、yonic stem cell research.Please consider.nWould the views of animal and human cloning differ among people with different religious believes?nIs embryo a living human?nSince the use of stem cells for therapeutic cloning is still in experimental stage,would the use of cells from embryo be acceptable?n

27、How about using the embryos left over after in vitro fertilization?Please consider.nIs reproductive cloning a violation of natural birth?nHow about the cloning of a beloved one who dies accidentally?nHow about cloning for sterile couples?nUnder what circumstances do you want to make a copy of yourself?End