The Cloning Debate: Science, Law, and Ethics

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The Cloning Debate:
Science, Ethics, and the
Law
Danielle Haller, Jason Saunders,
Lori Short, Jesse Warner
Cloning: What is it?
 The production of multiple, exact copies of
a single gene, DNA fragment, cell line, or
organism.
 3 types of cloning technology today:
recombinant DNA technology, reproductive
cloning, and therapeutic cloning
Cloning: A History
 1952: Scientists clone frogs from blastula cells, but fail to
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produce tadpoles from differentiated cells.
1962: John Gurdon claims to clone frogs using the nucleus
of an adult intestinal cell. Others were unable to reproduce
his results, his findings were called into question.
1966: Discovery of which codons specify the amino acids.
1973: E. coli turned into first recombinant DNA organism.
1977-1979: Illmensee claims to have cloned mice. Others
fail to clone mammals, deem his work “scientifically
worthless.”
1983-1986: Various mammals are successfully cloned from
embryonic cells.
1990: Human Genome Project begins.
1996: Dolly is born.
2004: Dr. Hwang Woo Suk claims to have cloned human
embryos. His work is not able to be replicated.
2006: Dr. Hwang fired from Seoul University as evidence
arises he faked some of his work on stem cells.
Recombinant DNA Technology
aka DNA cloning, gene cloning, or molecular cloning
 The gene of interest is cut from the genome
using restriction enzymes.
 It is then joined with a similarly cut DNA
molecule, a plasmid. The plasmid is known as
the cloning vector.
 Plasmids are circular molecules found in
bacteria that are separate from the bacterium’s
normal genome.
 Plasmids are self-replicating, allowing the new
recombinant DNA molecule to produce its gene
product in its new environment.
•Plasmids are not the only cloning
vectors that can be used, but they
are very common.
•Each vector has a limitation to the
size (in base pairs) of the DNA
fragment that can be cloned.
•This technology has been used
since the 1970s; it is fairly
common practice in molecular
biology labs today.
http://www.ornl.gov/sci/techresources/Human_G
enome/publicat/primer/fig11a.html
Reproductive Cloning
 The generation of a new animal that has the same
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nuclear DNA as a previously existing animal.
Artificial Embryo Twinning: A blastomere is induced
to split, forming identical twins.
Nuclear Somatic Transfer: The nucleus of an adult
body (somatic) cell is transferred into an egg which
has had its nucleus removed. After treatment to
make it begin dividing, the embryo is transplanted
into a host uterus.
Dolly was created using nuclear somatic transfer.
Extremely inefficient, most eggs do not develop into
an organism.
http://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Cloning_diagram_english.pn
g/300px-Cloning_diagram_english.png
Therapeutic Cloning
 Uses the process of nuclear somatic transfer to create
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an embryo.
However, the embryo is destroyed and harvested for
stem cells.
Stem cells are undifferentiated and retain the ability to
develop into many cell types depending on their
potency.
Totipotent cells can develop into any tissue in the human
body, plus tissues needed for development such as
placental cells.
Pluripotent cells can develop into almost all cells, but
cannot produce a new organism.
Therapeutic Cloning
 Also multipotent and unipotent cells that can only
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develop into a specific tissue or cell type. These are
obviously less useful.
These cell cultures are maintained in a “lineage.” Dr.
Hwang claimed to have several human stem cell
lineages.
An embryo must be destroyed, whether it be naturally or
artificially created.
Can possibly use stem cells to treat cancer, regrow
damaged nerve or muscle cells, etc.
Due to the controversy stirred by recent events, it is
unclear how far science has progressed towards
creating and maintaing human stem cell lines.
But what about behavior?
 Genetic manipulation can lead to behavioral
manipulation as long as there is a genetic
component to behavior.
 The evidence is strong that many behaviors are
at least partly affected by genetic components.
 First, we are infants in this science. Much of
what follows is supposition. We estimate there
are 30-35,000 genes in the human genome. We
do not agree on what constitutes a “gene,” nor
do we know what most genes do. Some genes
are pleiotropic, meaning they have multiple
effects, sometimes at different stages of life.
Genetics and Behavior
 Aggressiveness, altruism, assertiveness,
impulsivity, and persistence have an estimated
heritability of >40%.
 Borderline personality trait disorders have an
estimated heritability of ~69%.
 Including all proteins and neurotransmitter
systems, behavioral phenotype is around
50% genetically determined give or take a
few wild estimates.
Possibilities
 So, cloning could be used to at least influence
some aspects of human behavior.
 Recombinant organisms could produce a
specific gene product to be introduced in
therapy.
 The embryo could be manipulated after
fertilization.
 Therapeutic cloning/gene therapy could alter an
organism’s genotype.
Possible Benefits of Cloning
Genetically-Modified Animals
 The possibility of xenotransplantation
(organ transplantation from 1 species to
another) Pig hearts, for example
Immuno-suppressed animals
 Disease-resistant Farm Animals
 Crops that are disease, insect, and
drought resistant
Transgenic Animals
 Allows for the creation of a vast amount of
new drug development
Lower cost
Higher efficiency
Infertility Patients
 Will allow infertility patients to have their
own biological child (current infertility
treatments are only about 10% effective
and very costly both monetarily and
mentally on the parents)
 Will allow parents to have offspring that
are free of genetic disease (cystic fibrosis,
Huntington’s, etc…)
Cosmetic Surgery
 Plastic surgeries,
breast
augmentations,
reconstructive
surgeries would be
much safer
 Doctors will be able to
manufacture bone,
fat, connective tissue,
or cartilage that
matches the patients
tissues exactly
 This would prevent
problems with silicone
leaking or immune
disease associated
with plastic surgery
New Possibilities for Organ
Transplants
 Organs, such as livers and kidneys, could
be cloned
 These clones would be more successful
than current transplants because they are
created from the patient’s body and would
be free of immune disease reactions
 Also, immuno-suppressed animals can
harvest organs for more options
Rejuvenation
 A human’s DNA begins to break down
when the baby is about 6 months old
 Some researchers believe that some of
the effects of aging could be reversed in
the future with the use of cloning
Health Improvement Opportunities
 Heart Disease- New heart cells can be cloned and
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injected into areas of damaged heart tissue
Defective Genes- The average person has 8 defective
genes, which could be replaced by cloning
Tay-Sach’s Disease- an autosomal recessive genetic
disorder that could use cloning to prevent the expression
of the gene for the disorder
Spinal Cord Injury Victims- New nerves or spinal cord
could be re-grown with cloning (this could combat
paralysis and allow quadriplegics the opportunity to walk
again)
Genetic Testing- Cloning could make it easier to test for
as well as to cure genetic diseases
Scientific Concerns/Risks
Involved in Cloning
Extremely High Failure Rate
 Animal cloning has proven highly unsuccessful
 Dolly (sheep)- only 20 embryos grew out of over
400 attempts
 Snuppy- due to the highly complicated
reproductive system of dogs, the South Korean
team only obtained three pregnancies from more
than 1,000 embryo transfers into 123 recipients
 Kittens have very little success as well
Problems During Later
Development
 Out of the 20 sheep embryos that grew, 19 were
either stillborn or stopped developing due to
birth defects (Dolly was the only survivor out of
over 400 attempts)
 1 of the 3 puppy embryos that was growing
miscarried and 1 died shortly after birth (Snuppy
was the only survivor out of over 1,000 attempts)
 Most clones are born with Large Offspring
Syndrome (they are abnormally large) This
means they have larger organs, which leads to
breathing, blood flow, and other problems
Abnormal Gene Expression
 Direct comparison of gene expression profiles of more
than 10,000 genes showed that for both donor cell types
approximately 4% of the expressed genes in the NT
placentas differed dramatically in expression levels from
those in controls and that the majority of abnormally
expressed genes were common to both types of clones
 This study done by MIT on mice also showed an
abnormal gene expression in the livers of cloned mice
 The clones may express different amounts of different
genes than normal humans or animals at different times
Telomeric Differences
 As cells divide, their chromosomes get
shorter because their telomeres shrink
each time
 If the transferred nucleus is older,
telomeres could be shorter than normal in
the clones produced
 Dolly had shorter than normal telomeres
 Scientists do not know the ramifications of
differences in telomeric length
Is Cloning Ethical?
Yes or No?
What do you think?
Aspects of Ethics
 Nonmaleficence (Doing No Harm)
 Beneficence (Doing Good)
 Autonomy
 Justice
 Formal
 Material
Does Cloning Maintain NonMaleficence?
 Risk factors involved
 Mother/Surrogate, even Clone
 High percentage of animal clones have not
implanted or gestated due to genetic
abnormalities
 Reports of congenital malformation
 To date 5% of cloned animals live births
 Paul Billings, co-founder of GeneSage,
says that Cloning is not safe , Cloning is
not medically necessary, Cloning could
not be delivered in an equitable manner
 Billings has also said that stem cell
therapies have been “wildly oversold”
 http://www.genesage.com/index.html
 Oldest clone to date lived for 5 years
 Premature aging
 Immuno-failures
 Copying an aged cell (Dolly)
 Dolly developed arthritis very early on
 Cells being cloned may develop genetic
mutations very early on
 Recessive traits could be phased out
 Recessive traits critical to evolution
 Allele extinction can occur
 Lack of alleles mean less diversity
Does cloning maintain
Beneficence
 Improve the quality of life
 Can avoid defects that occur naturally
 Preserve and perpetuate good genes like
intelligence, physical attributes, and
physical skills
 Allows infertile couples to have children
 Also gives same sex couples ability to
have children
 In both cases the offspring can have traits
from each parent
 Ideal transplant donors for terminally ill
 Guaranteed match for specific blood type
and DNA match
 Would ensure organs won’t be rejected
 Could replace a loved one who died
prematurely
 You are clones
Autonomy of Cloning
 Does the clone consent to exist
 They could be used and abused
 DNA could be used without consent, living
or dead to make a clone
 They would be property in most cases
 Expectations to live up to
Justice
 Formal
 Cloning is very expensive
 Rich would benefit, cloning would only be available to
them
 Superior, genetically altered race vs. normal, natural
race
 Clone won’t stand next to humans as equal, they’re
created, property
 Billings says we need to work to better the situation of
the poor so that access to therapies is improved
 Material
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Should the government fund research
Currently USA is not funding any new research
Future of cloning is international
Dolly was cloned in Scotland
Should healthcare help lower the cost for people with
terminal illnesses
 Billings favors the “go slow approach”, until the
therapies are proven affective
Legal Aspects & Issues
Past Legal Standards
 Abortion is legal… why wouldn’t cloning be the same?
 Diamond v. Chakrabarty
 Question: Is the man-made creation of a live organism
patentable?
 Answer:
– Yes. “In a 5-to-4 decision, the Court explained that a live artificially-
engineered microorganism is patentable. The creation of a
bacterium that is not found anywhere in nature, constitutes a
patentable "manufacture" or "composition of matter.” Moreover, the
bacterium's man-made ability to break down crude oil makes it very
useful. ” *
– What does this mean for future precedence?
*source was http://www.oyez.org/oyez/resource/case/1125
Weldon Amendment
 Proposed by Representative Dave Weldon
 Passed in the House and moved to the
Senate in 2003, making it illegal to patent a
human organism, including a cloned one.
 Big step for Pro-Life supporters
•Wording is vague for “human organism”… what could
this mean?
California Proposition 71
 2004- Regulations allowing $300 million
per year for 10 years on embryonic and
adult stem cell research was “approved”
by the voters
 Created the California Institute for
Regenerative Medicine
 Independent facility that is awarded state
grant money
Proposition 71
 This could be seen as a means to go
around a federal funding ban on new
embryonic stem cell research.
 Is this ok?
•Could be a means to cure Alzheimer’s
disease or even diabetes… is it worth the
legal risks and ethical compromises?
Human Cloning Prohibition Acts
 2001- Initial attempt
 2003- Passed in the House and placed on the
Senate Calendar
 Amendment to Title 18 to the United States Code,
which defines terms and calls for financial review
 2005- Senate Proposed
 Amendment to the Public Health Services Act, which
makes definitions more clear
 Also calls for a determination if new medical
technologies are acceptable.
Current Legal Standards
 State Human Cloning Laws
 The Human Cloning Prohibition Acts of
2001, 2003 & 2005 are currently being
heavily debated in Congress– no doubt
there will be many more… will government
give in?
 Arguments on each side
 Supporters of Pro-Life
 Supporters of medical research
Future Legal Considerations
 The fight to defend and protect the cloning
process is a two sided battle
 Who is really fighting for the overall legal
rights of people?
 Pro-life for the legal rights of cloned embryos?
 Pro-research for the legal rights of ill people that
are currently dieing?
• Needs to be a compelling state interest in
order to ban cloning. Will this ever be
realistic?
Thank you!
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