Cloning For Every Man

1. Cloning For Every Man Timothy G. Standish, Ph. D.

2. “The cloning of mammals . . . is biologically impossible.” James McGrath and Davor SolterScience, Dec. 14, 1984

3. “Our announcement of Dolly’s birth in February 1997 attracted enormous press interest, perhaps because Dolly drew attention to the possibility of cloning humans. This is an outcome I hope never comes to pass.” Ian WilmutScientific American, December, 1998

4. What This Talk Is About • What is cloning? • How is cloning achieved? • Why Clone? Why would anyone want to clone an animal or human? • Ethical Considerations? Why should cloning technology be carefully thought through before being widely used and particularly before humans should be cloned? Four Questions:

5. Organism . Organ System Cell Nucleus Tissues The Code For Life

6. Chromosome Nucleus Genes The Code For Life Big nose Brown eyes Straight hair

7. The Nucleus Contains An Organism’s Blueprint • Every cell has a nucleus when it is made • Within every nucleus is a complete copy of the organism’s genetic code • Differences between cells result from different genes being “expressed” in different ways

8. Clones • Clones are two genetically identical organisms • Nature commonly produces clones • Most bacteria reproduce by “binary fission” in which the mother cell splits in two with a complete copy of the genetic information being passed to each daughter cell • Many single-celled eukaryotic organisms reproduce in a similar way • In higher organisms, clones also occur naturally, but usually through some more complex mechanism

9. Plant Clones • Any time that plants are reproduced using cuttings to produce new separate plants, they are being cloned • Many commercially important strains of fruits are produced from clones • Seedless plants can only be reproduced as clones

10. Animal Clones • Animal clones may result from “budding” as a way of reproducing • Budding is common in corals and some other animals • Some vertebrates reproduce via parthenogenesis

11. Natural Human Clones • Identical twins result from the splitting of an embryo into two separate cell masses which both go on to develop into genetically identical twins • This happens naturally in about 3/1,000 births • Identical twins are genetically identical because they have identical genes in their nucleus • This does not mean they are truly identical

12. How Is Cloning Done? • Making a clone is, in theory, a very simple thing • All one has to do is take a cell with the nucleus of the organism you want to clone, and grow it into a new organism • The difficulty is that most cells do not readily grow into whole new organisms

13. Barriers To Cloning Mammals • Most cells seem to have a limit to how many times they will divide (the Hayflick limit) • A complex interplay between nucleus and cytoplasm exists that prevents most cells from producing cells other than their own type • During development, cells differentiate into all the cell types in the body, but they do not readily go back to being undifferentiated • The egg and a few early cells in an embryo are the only cells capable of developing all the cell types necessary to make a whole mammal

14. Overcoming The Barriers A nucleus needs the right cytoplasm environment if it is to become “totipotent” • Eggs provide the correct environment The nucleus must be “reset” so that it forgets it was in a differentiated cell • Ian Wilmut learned that starving cells in culture reset their nucleus Cells developing from mammal eggs do not seem to have a limit to the number of times they will divide

15. Making A Clone The method for making a clone used by Ian Wilmut includes 6 steps: 1 Production of quiescent cells containing nuclei that “forget” the type of cell they are in 2 Collection of the donor nucleus 3 Preparation of an egg lacking genetic material 4 Insertion of the donor nucleus 5 Initiation of development 6 Development of the embryo in a surrogate mother

16. Mammary gland cells Finn Dorset ewe 3.5 months pregnant Harvest quiescent cells How Ian Wilmut Made Dolly 1Making Quiescent Cells Culture mammary cells Starve cells

17. Glass pipette Suction Pipette Suction How Ian Wilmut Made Dolly 2Collecting The Donor Nucleus

18. Suction Pipette Suction How Ian Wilmut Made Dolly 2Collecting The Donor Nucleus Glass pipette

19. Egg Scottish Blackfaced ewe egg donor How Ian Wilmut Made Dolly 3Egg Preparation An egg is collected then placed into a dish where it can be manipulated

20. Glass pipette Chromosomes Suction Pipette Suction How Ian Wilmut Made Dolly 3Egg Preparation Egg

21. Chromosomes Suction Pipette Suction How Ian Wilmut Made Dolly 3Egg Preparation Glass pipette Egg

22. Glass pipette Suction Pipette Suction How Ian Wilmut Made Dolly 4Inserting The Donor Nucleus

23. Suction Pipette Suction How Ian Wilmut Made Dolly 4Inserting The Donor Nucleus Glass pipette

24. Suction Pipette Suction How Ian Wilmut Made Dolly 4Inserting The Donor Nucleus

25. How Ian Wilmut Made Dolly 5Initiating Development

26. How Ian Wilmut Made Dolly 5Initiating Development Zygote

27. How Ian Wilmut Made Dolly 5Initiating Development Cleavage

28. How Ian Wilmut Made Dolly 5Initiating Development Cleavage

29. How Ian Wilmut Made Dolly 5Initiating Development Cleavage

30. How Ian Wilmut Made Dolly 5Initiating Development Cleavage

31. How Ian Wilmut Made Dolly 5Initiating Development Morula

32. Morula Scottish Blackfaced ewe surrogate mother Finn Dorset lamb Dolly How Ian Wilmut Made Dolly 6Development

33. Why Clone? Cloning provides opportunities in four major areas 1 Study of development Production of genetically identical organisms that can be studied in different environments has the potential to dramatically advance our understanding of development 2 Propagation of valuable organisms 3 Control over reproduction 4 Production of recombinant organisms 5 Production of engineered organs

34. Propagation Of Valuable Organisms • There are limits to the possibility of reproducing valuable combinations of traits using traditional breeding techniques • For example, race horses are regularly bred to produce fast offspring, but occasionally an excellent combination of traits if produced that cannot be repeated even when the same parents are used • Cloning could produce many copies of Pharlap or other valuable horses

35. Control Over Reproduction • Production of a clone allows very precise predictions about the results of a pregnancy • Cloning offers the potential to produce genetically related offspring from sterile organisms • Before cloning cells can be engineered to remove genetic defects, or introduce desired traits

36. Production OfRecombinant Organisms • Cloned organisms can be made from cultured cells • It is relatively easy to introduce new genes into cell cultures • Cells from recombinant cell cultures can be used as nucleus donors for clone production • This technique has already been used by researchers at the Roslin Institute to produce recombinant sheep that make human factor IX • Factor IX is used to treat hemophilia B

37. Production Of Engineered Organs • The potential exists to engineer organisms that produce organs which will not be rejected when introduced into humans or other needy recipients • To do this, animals would be produced that do not make the proteins and other chemicals on cell surfaces that tell the immune system they do not belong in a human body

38. Why Clone Humans? • Production of genetically related offspring by infertile couples for whom other reproductive technologies have failed • Narcissism • Replacement of lost loved ones • Production of genetically “improved” humans (custom-built babies) • Production of spare parts for those needing replacement organs

39. Ethical Considerations • All new technologies have unforeseen effects. We cannot expect that cloning will be without unexpected benefits and problems • Is any reproductive technology tampering with the way God made nature to work? • Are we “playing God” when we create organisms “designed” by humans? • Will there be abuses of the ability to produce engineered organisms . . . ?

40. Ethical Considerations • Production of large numbers of clones would lower genetic diversity • Cloning technology makes other technologies more practical: • Production of cloned body parts requires the production of embryos that are then used as a source of stem cells

41. The Ethics Of Human Cloning • Would cloning be in the best interest of the child? • How would a child react to knowing how they will develop in the future? • What expectations would society put on cloned children? • Is it ethical to produce a life/potential life for the purpose of saving or enhancing the life of a living person? • Is producing a clone as a source of stem cells, then discarding the remaining parts, equivalent to abortion?

42. Who Owns A Person’s Genetic Potential? • It would be immoral to take the gametes of a person and, without their consent, use them to produce offspring • Cloning offers the potential of making genetic copies of anyone -- With or without their consent

43. Recent Developments In Cloning • 1999 - A number of cloned cows and other organisms have died without explanation. In general clones are less healthy than offspring produced using other methods (Lancet, U.S. News and World Report, May 24, 1999) • Dolly has chromosomes with telomeres shorter than those of other ewes her age. Dolly’s lambs have telomeres that are normal in length for sheep their age (Nature, May 27, 1999) • The first male has been cloned from adult cells, named Fibro by Yanagimachi’s group in Hawaii, cells from an adult mouse tail were used as the source of 274 nuclei, one of which developed to adulthood and fathered two normal litters (Nature Genetics, May or June 1999)

44. Recent Developments In Cloning • 1999 - Discovery of a frozen woolly mammoth in Siberia has presented the possibility of cloning mammoths using a mammoth nucleus and elephant eggs (http://cnn.com/NATURE/9907/23/mammoth.reut/) • 1999 - A group in New Zealand has approved the cloning of the extinct Hula bird using preserved materials (http://cnn.com/NATURE/9907/20/cloning.enn/) • 1999 - Dolly is shown to have different mtDNA than the ewe from whom she was cloned, but the same mtDNA as the mother who donated the egg (Eric Schon, Ian Wilmut et al., September 1999 Nature Genetics)

45. The first documented human clone Cloning Humans Using Cow Eggs • June 17, 1999 American Cell Technology (ACT) announce they had made a human clone during November 1998 • The clone was made by inserting a human nucleus from skin on a man’s leg into an enucleated cow’s egg • After developing for 14 days the clone was destroyed (Researches said before 14 days it “was not human”) • Clones of this type may be potential sources of stem cells and perfect tissue matches for those needing transplants • According to the BBC, Lord Robert Winston, a British fertility expert, said the research was "totally ethical” • This information came from the BBC web page news.bbc.co.uk/hi/english/sci/tech/newsid_371000/371378.stm

46. “None of the suggested uses of cloning for making copies of existing people is ethically acceptable to my way of thinking.” Ian WilmutScientific American, December, 1998

47. The End