HYBRID HUMANS:

WHAT'S AT STAKE?

Dennis M. Sullivan, MD, MA (Ethics)Director, Center for Bioethics

Cedarville UniversityCenter Web Site: www.cedarville.edu/bioethics

E-mail: sullivan@cedarville.edu

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

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.

“Look at him – So high and mighty with his fancy hybrid!!”

CHIMERA: THE ULTIMATE HYBRID

Homer's Iliad:– “A thing of immortal make, not human,

lion-fronted 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.

HYBRIDS IN THE MEDIA

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

Maybe I'm just a duck, but I'mhuman.— Donald Duck, Early to Bed

-- 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 wearpants. But I talk and live in ahouse, so you know whatI had in mind.-- Duckman

MIXING IT UP:WHERE HAVE

WE BEEN?

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

ETHICAL QUESTIONS

Natural Law concerns (minimal)

Utilitarian concerns–May be risky (primarily related to

rejection)– Animal to human disease transmission

Animal rights

MIXING IT UP A BIT MORE:WHERE ARE

WE GOING?

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.

TRANSGENIC FISH:

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

MIXING IT UP STILL FURTHER:

ARE YOU NERVOUS YET?

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

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 citedcan pass altered genes to their offspring

MIXING IT UP: WHAT ARE

THE LIMITS?

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;

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.

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

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?”

QUESTIONS?

HYBRID HUMANS:

WHAT'S AT STAKE?

Dennis M. Sullivan, MD, MA (Ethics)Director, Center for Bioethics

Cedarville UniversityCenter Web Site: www.cedarville.edu/bioethics

E-mail: sullivan@cedarville.edu