HYBRID HUMANS: WHAT'S AT STAKE?

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1 Dennis M. Sullivan, MD, MA (Ethics) Director, Center for Bioethics Cedarville University Center Web Site: HYBRID HUMANS: WHAT'S AT STAKE?

2 OBJECTIVES To survey new biotechnologies that cross species barriers, especially as it relates to human beings To examine the bioethical questions raised by such research To attempt to delineate a bright line between the ethical and the unethical

3 WHAT IS A HYBRID? Linguistics: the process of one language variety blending with another variety. Automobiles: the alteration of a vehicle to run on two fuel sources. Chemistry: the mixing of atomic orbitals to form new orbitals suitable for bonding. Molecular Biology: the process of joining two complementary strands of DNA. Genetics: combining different varieties or species of organisms.

4 Look at him So high and mighty with his fancy hybrid!!

5 CHIMERA: THE ULTIMATE HYBRID Homer's Iliad: A thing of immortal make, not human, lionfronted and snake behind, a goat in the middle, and snorting out the breath of the terrible flame of bright fire. Finally defeated by Bellerophon, with the help of Pegasus, at the command of King Iobates of Lycia. Since Pegasus could fly, Bellerophon shot the Chimera from the air, safe from her heads and breath.

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8 HYBRIDS IN THE MEDIA

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11 Australian artist Patricia Piccinini's concept of what human-animal hybrids might look like

12 Maybe I'm just a duck, but I'm human. Donald Duck, Early to Bed

13 -- I am not an animal! Hear me? I'm not an animal. Well... okay, maybe I am kind of an animal, I'm a duck. And I don't wear pants. But I talk and live in a house, so you know what I had in mind. -- Duckman

14 MIXING IT UP: WHERE HAVE WE BEEN?

15 TRANSPLANTATION: Autotransplantation (e.g., skin grafts) Allotransplantation: Kidney transplants Bone marrow transplants Adult stem cells (auto- or allo-) Xenotransplantation Crossing the species barrier Such cells, tissues or organs: xenografts Examples: porcine valves, baboon heart, bovine pancreatic tissue, temporary porcine skin grafts

16 ETHICAL QUESTIONS Natural Law concerns (minimal) Utilitarian concerns May be risky (primarily related to rejection) Animal to human disease transmission Animal rights

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19 MIXING IT UP A BIT MORE: WHERE ARE WE GOING?

20 HUMAN/ANIMAL TRANSGENICS Transgenic animals: DNA from another species inserted into their genome Transgenic sheep and goats: express foreign proteins in their milk Transgenic chickens: synthesize human proteins in the white of their eggs.

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22 TRANSGENIC FISH:

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24 A MEDICALLY USEFUL EXAMPLE: Normal mice: resistant to human polio virus Why? Lack cell-surface molecule that serves as the receptor for the virus Transgenic Mice: Express the human gene for the polio virus receptor Therefore: can be infected by polio virus and even develop paralysis Inexpensive, easily-manipulated model for studying the disease

25 MIXING IT UP STILL FURTHER: ARE YOU NERVOUS YET?

26 TRANSGENICS: HOW MUCH IS TOO MUCH? Transgenic pigs: So far just a theory Knock out the genes that code for two key molecules that trigger rejection Ultimate goal: genetically engineered pigs as a source for transplantable organs for humans Mouse-Human Chimera: Human stem cells put into brains of fetal mice Human cells divide and grow in mouse brains Model for studying human neural diseases

27 THE ETHICS OF TRANSGENIC PIGS: Natural Law Concerns More substantial Seems unnatural Biblical Concerns Proscription of bestiality Exodus 22:19; Leviticus 18:23 Leviticus 20:15-16; Deuteronomy 27:21 But these all deal with sexual relations But: None of the examples cited can pass altered genes to their offspring

28 MIXING IT UP: WHAT ARE THE LIMITS?

29 SB 243: OHIO BAN ON ANIMAL-HUMAN HYBRIDS Passed in 2010 by Ohio Senate Bans the following: Creation of a human embryo where it is uncertain whether the human embryo is a member of the species homo sapiens; A hybrid human-animal embryo produced by fertilizing a human egg with a nonhuman sperm; A hybrid human-animal embryo produced by fertilizing a nonhuman egg with a human sperm; An embryo produced by introducing a nonhuman nucleus into a human egg;

30 SB 243 (CONTINUED) Bans: An embryo produced by introducing a human nucleus into a nonhuman egg; An embryo containing chromosomes from both a human and a nonhuman life form; A nonhuman life form engineered with the intention of generating functional human gametes within the body of a nonhuman life form; A nonhuman life form engineered such that it contains a human brain or a brain derived wholly from human neural tissues.

31 WHY IS ALL THIS WRONG? God created species to reproduce after their kind (Gen. 1:24) Humankind is made in the image of God (Gen. 1:26-28) Human dignity is grounded in a strong sense of human nature The ultimate in technological hubris: Transhumanism The human re-engineering project Gen. 1:31 inverted

32 C. S. LEWIS (THE ABOLITION OF MAN): Human nature will be the last part of Nature to surrender to Man. The battle will then be won But who, precisely, will have won it?

33 QUESTIONS?

34 Dennis M. Sullivan, MD, MA (Ethics) Director, Center for Bioethics Cedarville University Center Web Site: HYBRID HUMANS: WHAT'S AT STAKE?