Transcript Human Cloning - Dartmouth College

HUMAN
CLONING
The Good
The Bad
Eliot Grigg
Dartmouth College
March 25, 2003
The Bizarre
Medieval Medicine
Experiment without
understanding
mechanisms
 Assumption that all cells in
body have same genetic
information
 Turning back the
developmental clock on a
cell – reprogramming
process not understood

History of Cloning
1960’s and ’70’s:
Nuclear transfer in
frogs – John Gurdon
 1996: Megan and
Morag – lambs
created from
aborted fetus cells
 1997: Dolly – First mammal cloned from an
adult cell – Dr. Ian Wilmut
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Recent Cloning Events
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Dolly dies young in
February – short
telomeres
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Shorten when cell divides
(except cancer cells)
Italian fertility doctor Severino Antinori
 Chinese cloning program
 Clonaid - announced first clone baby born
on December 26, 2002 – thought to be a
hoax by Raelian movement
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How to Clone
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Nuclear Transfer
1. Extract DNA from oocyte (egg)
2. Extract DNA from donor cell in G0 stage of
cycle
3. Inject DNA into empty oocyte and fuse with
electricity
4. After a few division in culture, implant in
surrogate mother
How to Clone (2)
Technical Hurdles
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Complications
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Dolly result of 277 attempts, dies young
2-3% success rate elsewhere
Developmental problems: lungs, immune system,
weight gain
Why?
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Cell cycle coordination
Reprogramming process: time compression
Methylation: signals to genes disturbed in handling
Oct4 gene improperly regulating?
Animal Cloning
Bucardo, Spanish
Mountain Goat
 Livestock
 Frozen Zoo
 Jurassic Park
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Cloning and Medicine
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Therapeutic Cloning

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Cloning allows for specific genetic
engineering because one modified cell grows
into an entire organ / organism
Reproductive Cloning
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Cloning makes new people from an adult cell
Xenotransplantation
Transplanting organs
from other species
 Goldie the pig lacks
gene alpha-1galactosyltransferase:
codes for sugar on cell
surface that is identified
by human antibodies
– Randall Prather
 Retrovirus in pig DNA
transferred to humans?

Therapeutic Cloning

Therapeutic Cloning
1.
2.
3.
4.
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Extract DNA from adult cells
Create cloned embryos
Extract embryonic stem cells
Destroy embryo
Spare Parts
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Direct tissue engineering of spare parts on
demand – begin with one cell, modify it, and
grow into organ
Genetically identical to recipient – no rejection
Therapeutic Cloning (2)
Grow whole organs – alleviate organ
shortage
 Grow non-regenerating cells
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Brain cells for Parkinson’s
 Pancreatic islet cells for Diabetes
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Note: we do not yet have command of
stem cells
Reproductive Cloning
Cloning entire people
 Infertility
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Genetically related offspring for infertile,
gay/lesbian couples
Offspring for families with inheritable genetic
disorders
Add genetic engineering for designer babies
 Raise the dead [see handout]

The Legal Landscape

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Distinction between Reproductive and Therapeutic
Cloning
In USA:
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Total cloning ban passed the
House but awaits Senate –
President Bush support
Federally funded institutions
must only use existing stem cell lines
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UN: Talks suspended for global cloning ban
Human cloning illegal in South Korea, legal in China
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If we ban it here, it will happen somewhere else
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Ethics – Patents

Patents do not cover “things
found in nature” but do cover
“things discovered or made by
man”
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Patent on a gene
Patent on technique and
sometimes its product…
i.e. drug, novel organism
Patent on transgenic organism
containing human genes
Patent on a human clone?
Ethical Objections
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Theological
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Technical
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Failures and deformities – unsafe (for now)
Creepy Applications
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Playing God, Taking life
Parent from beyond the grave
Headless organ donors
Identity
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Is clone a distinct person from DNA donor?
Clones vs. Twins vs. Carbon Copies
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Donor DNA
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Surrogate mother
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Telomere shortening
Epigenetics: turning off one copy
of every gene (from mom or dad)
Conditions in the uterus
Oocyte doing reprogramming
Mitochondrial DNA
Nurture – unique upbringing
environment
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Buttercup
Old and New Ethical Dilemmas
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In Vitro Fertilization (IVF)
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Abortion
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Accepted by society
Legal, if contested
Coming soon… Face / Head Transplants
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Similar identity crisis – dates back to
Descartes (at least)
Designer Babies and
Genetic Determinism
Preventive Genetic Engineering  Enhancing Genetic
Engineering
 “In the not-too-distant future, it will
be looked at as foolhardy to have a
child by normal conception.”
Dr. Gregory Stock of UCLA
 The Genetic Divide
 Eugenics – an advantage for future
goals, not a guarantee…
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Conclusion
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Apocalyptic Scenarios
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Headless organ donors
Genetic Divide
Society without men
Medical tool … Art Form?
 Educate lawmakers / society
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If we had cured Beethoven’s depression,
would we still have his music?
[What is the nature of human nature?]