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The Ethics of Genetics
Lecture 1
January 20th 2010
Dr. Ruth Pilkington
Medical Ethics Year 2
1
Following the announcement of the mapping and sequencing
of the first draft of the human genome in 2000, it was
predicted that this would bring about ‘a new understanding of
genetic contributions to human disease and the developments of rational
strategies for minimizing or preventing disease phenotypes altogether...’
(Collins 1999)
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The belief that there is direct causal connection
between genotype and disease phenotype was
exaggerated
Other factors come into play e.g.
Penetrance (the % of people with the gene that develop the
corresponding feature), low or no penetrance, ‘forme fruste’, may
still pass on to next generation and cause a full disease
phenotype (i.e. appears to ‘skip a generation’)
Expressivity (the extent to which the gene is expressed in the
person)
Sex-limited (affected by hormones, e.g. male pattern baldness)
Chromosomal inactivation (X chromosome)
Genomic imprinting (one parental allele expressed only)
Codominance (e.g. blood type)
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Monogenic
Only a small number of diseases
Polygenic
Number of gene mutations, e.g.
cancer
Multifactorial Most diseases
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Monogenic disorders
Single gene mutation / Rarely complete penetrance
Monogenic
Autosomal dominant
(e.g. Huntington’s Dx)
Autosomal recessive
(e.g Cystic fibrosis)
X-linked
(e.g Haemophilia, Duchenne’s Musc. Dystrophy)
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Hence, there is ambiguity in the genetic component
in most diseases.
Having a mutation does not necessarily mean
that one will develop the disease associated with
it.
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Genetic Testing
&
Screening
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Genetic Testing / Screening
Genetic testing –for individuals who are known to
be at increased risk of having a genetic disorder
with a familial mode of inheritance.
Genetic screening –to test members of a particular
population for a disorder for which there may be
no family history or other evidence of its
presence.
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Genetic Testing / Screening



1
Purpose - To prevent harm to people who would develop
genetic diseases during their lives, e.g. causing people to
exist with these diseases can harm them by defeating
their interest, once they exist, in living without pain,
suffering, and limited opportunities, relief of anxiety,
etc.
Dangers – A predisposition to a disease is no guarantee
that one will develop that disease (in the case of nonmonogenic disease).
Dangers – Insurers or employers might discriminate
against individuals on the basis of the genetic
information.
1Glannon,
Biomedical Ethics, OUP
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Considerations of Harm
‘New knowledge about the risk of genetic transmission of
diseases and other harmful conditions will give
individuals both the opportunities and the responsibility
to choose whether to transmit such harms to their
offspring or to risk doing so.’1
1Buchanan,
Brock, Daniels & Wikler, From chance to choice, Cambridge, p.204
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Considerations of Harm
For the individual :
What actions and interventions are morally
required to prevent harm?
and
What actions and interventions are morally
permissible to prevent harm?
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Considerations of Harm
Is there a role for Society?
Education...
Is there a role for the law?
Legal measures...
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Huntington’s Disease
•
•
•
•
Monogenic disease / Autosomal dominant
50% of offspring affected
Severe debilitating disease with onset usu. 30’s – 40’s.
Irreversible motor and cognitive degeneration.
Ultimately fatal.
Virtually 100% penetrance hence people with the
Huntington's mutation are at very high risk of
developing the disease and the consequent physical and
psychological risk.
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Huntington’s Disease
Considerations of harm
•
•
•
•
Unfortunately, by the time the symptoms appear, the affected
individual has had children and so the gene and disease may
already have passed on into the next generation
In spite of there being no treatment for the disease, there would
be an obligation on an individual with a family history and early
symptoms to test and so provide the information to children that
they might make decisions and life choices based on this
information while there is time.
Thus testing for the prevention of harm, i.e. to allow the children
make decisions about having children themselves and to allow
prudential life choices to be made.
The point is to allow those at risk for the disease to make
informed choices.
1Glannon,
Biomedical Ethics, OUP
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Familial Breast Cancer
Considerations of harm
•
•
•
•
•
•
BRCA1 and BRCA2 gene mutations
Significantly high risk of breast (up to 85%) and ovarian (up to
60%) developing over a lifetime.
Female and male offspring - 50% chance of inheriting
A woman with a suggestive family history but without sisters or
offspring – has no obligation to test except for prudential
interests, e.g early mammography
A woman with breast cancer and a family or sisters – has on the
other hand an obligation –to clarify the risk to her family
However that obligation not as strong as the one in the case of
Huntington's disease, because 50-85% vs. 100%
1Glannon,
Biomedical Ethics, OUP
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Genetic
Screening
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Tay-Sachs
•
•
•
•
Recessive disorder, hence parental carriage
c.f. Ashkenazi Jewish population
Children born normal but develop degenerative
neurological disease culminating in death by age
3 or 4
Pre-conceptive genetic screening of an at risk
population
Screening couples intending to conceive
1Glannon,
Biomedical Ethics, OUP
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Tay-Sachs
•
•
•
Decrease in incidence since screening of Orthodox
Jewish community since 1970s
Reduction due to carriers avoiding marriage, carrier
couples undergoing prenatal testing and terminating
affected foetuses or embryos, the use of donor
gametes, and adoption
Adolescent screening particularly. Prudential and moral
implications – allows ample time to plan future in
accord with their values. Enables them to prevent harm
to children who would be born with Tay-Sachs.
1Glannon,
Biomedical Ethics, OUP
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Phenyketonuria (PKU)
•
•
•
The most compelling case for genetic screening is for
disorders that can be treated through non-genetic
means, e.g. PKU
PKU recessive disorder, the body fails to metabolise the
amino acid phenylalanine. Can lead to severe mental
retardation in affected children.
Special diet limiting the intake of phenylalanine avoids
the condition hence neonatal screening. So prevents
harm.
1Glannon,
Biomedical Ethics, OUP
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Genetic Testing
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Genetic testing
Of Note –
Genetic testing differs from most other medical
testing on a patient in that results may provide
significant medical information not only for the
patient but also for their genetically related
relatives.
Who owns this information?
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Genetic testing
Cases
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Case
1
1
A couple, Anna and Colm attend a genetics clinic. Their
newborn baby has been diagnosed with a severe & disabling
autosomal recessive condition (it is likely that the child will
die in the first year).
Prenatal diagnosis may be possible in a future pregnancy.
Autosomal Recessive condition, hence there is a 25%
chance that a subsequent child could be affected. The
carrier frequency of the recessive gene is 1 in 1000.
1
Adapted from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
1
Molecular analysis of blood samples shows that Colm is
not the biological father.
?
Should the geneticist disclose the finding of nonpaternity to the parents?
They did not seek information on paternity, however, it is
of direct relevance to their understanding of the
probability of an affected child in future pregnancies.
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
1
‘Options’
White lie’ to Colm and Truth to Anna (anecdotal
evidence)
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
1
Respect for Colm’s interests requires the truth.
Doctors should not lie to their patients
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
2
A woman whose mother has Huntington’s
disease tests positive for the gene mutation,
although she is not, as yet, symptomatic herself.
During post test counselling, she reveals that she
donated eggs to a private fertility clinic 6
months previously. She refuses permission for
the counsellor to contact the clinic because she
is afraid she will get into trouble.
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
2
?
Should the doctor breach the patient’s
confidentiality here.
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
2
Professional guidelines do not suggest that doctors
should break confidentiality because a patient
may have broken the law;
However here a child may be born with a very
serious genetic condition.
1 Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
3
Ciara has a child (4 ) just diagnosed with Duchenne’s
Muscular Dystrophy (DMD), a severe, progressive
muscle-wasting disease assoc. with a life expectancy of
20-30 years. Ciara is a carrier of this X-linked
condition, hence risk of 50% of male children will be
affected.
Niamh, Ciara’s sister is 10 weeks pregnant. She doesn’t
know of her nephew’s diagnosis or the risk to her own
child.
Ciara has told her geneticist that she does not want the
information given to her sister, as she fears she will
terminate her pregnancy, which Ciara believes to be
wrong.
1 Adapted,
Parker & Lucassen (1994), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
3
Should the geneticist respect Ciara's wishes and keep the
genetic testing confidential?
or
Should the information from Ciara be used to test
Niamh and her foetus and provide Niamh with the
information she may require to make informed
reproductive choices?
1 Adapted,
Parker & Lucassen (1994), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case
1
3
Personal Account Model
Consider if harm to Niamh and her foetus is sufficiently
severe to justify a breach of confidentiality1. Would termination of the pregnancy be a greater
harm.
2. Would the harm of having DMD and not preventing
it be worse.
3. Existing with DMD vs. not existing at all
Adapted, Parker & Lucassen (1994), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Case 31
Joint Account / Property Model
Analogous to asking a bank manger not to reveal
information about a joint account to fellow account
holders.
Genetic information belongs not just to one person, but
to families. The presumption then is that genetic
information is to be shared with family members, unless
there is very good reason to exclude them from
knowing.
1Parker
& Lucassen (1994), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Genetic Testing
of Children
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Genetic testing and Children
For
•
•
•
•
•
•
Beneficial in making lifestyle or career choices
Self-knowledge promotes autonomous decision making
Testing resolves uncertainty, thus reducing anxiety
Testing respects parental autonomy
Participation of child promotes development of
autonomy
Early testing promotes better psychological adjustment
than later testing.
Adapted from Savulescu (2001), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Genetic testing and Children
Against
•
•
•
•
Fails to respect the child’s later autonomy to decide
whether to have testing or not, and violates the future
adult's ‘right not to know.’
Breaches child’s confidentialty, as parents will know the
result.
Testing may disturb family dynamics and thus harm
child and involve stigma, discrimination, development
of low self esteem, depression and anxiety.
Parents may develop a sense of guilt.
Adapted from Savulescu (2001), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Genetic testing and Children
Most strongly advise against testing children for a
disease in which surveillance, or pre-emptive or
definitive medical treatment, is not available in
childhood.
Inc. UK Clinical Genetics Soc.(1994), Am. Soc. For Human Genetics
(1995), Human Genetics Soc. Of Australia (2005)
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Incompetent Adults
Testing may amount to battery in law.
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Genetic Counselling
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Genetic Counselling
‘The process by which patients and their
relatives at risk of a disorder that may be
hereditary are advised of the consequences of
the disorder, the probability of developing and
transmitting it and of the way in which this may
be prevented or ameliorated.’1
1Harper
(1988), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Non-directive Counselling
is the ideal
In response to the coercive practices of eugenics
in the early 20th century.
To distance clinical genetics from those eugenic
practices.
Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Non-directive Counselling
•
Arguments for
Reduces risk of coercion
Patient is best placed to make decisions about
genetic testing
Patient’s values (not the counsellor’s) are most
important
Promotes active autonomous decision-making.
•
Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
•
•
•
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Non-directive Counselling
•
•
•
•
•
•
Arguments against
Not possible, because there will always be an inherent
bias in presenting the information.
Patients may want and need advice and direction
Denies patients moral dialogue about their choices
Allows ‘wrong’ decision making without discussion
No place left for persuasion
Inconsistent with other areas of clinical practice where
advice is given.
Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Non-directive Counselling
However is the non-directive approach
always the correct one?
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Non-directive Counselling
Séan’s Case1
Séan’s father died from bowel cancer at a young
age. He had a diagnosis of familial adenomatous
polyposis coli, a disease which involves the
development of multiple bowel polyps. These
lesions have a high risk over a lifetime of
becoming cancerous. Surveillance colonoscopy
and polyp removal is the treatment of choice. A
prophylactic colectomy may be indicated.
1Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Non-directive Counselling
Séan’s Case1
Séan’s genetic counsellor explains these disease
facts to him and that there is a 50% chance of
his having inherited the gene for the disease.
However Séan decides that he will neither have a
genetic test nor a colonoscopy. The counsellor
finishes by ensuring that Séan has understood
the key facts.
Two years later Séan develops bowel cancer and
dies.
1Adapted
from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Genetic Information
& The Law
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Clinical Practice
Pre-existing common law applies, as does legislation
regarding consent and confidentiality regarding the use
and disclosure of medical information, unless specific
legislation has been put in place.
International Instruments, e.g. Universal Declaration on the
Human Genome and Human Rights (UNESCO, 1997),
Convention for the Protection of human rights and dignity of the
Human Being with regard to the application of Biology and
Medicine (Council of Europe, 1997),
Human Tissue Act, 2004 (UK)– non-consensual analysis
of human DNA is an offence.
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The Law and Genetic Information
•
•
•
•
•
The traditional confidentiality approach – is medical
confidentiality absolute?
A human rights approach c.f. Article 8(2) of Human
Rights Act would justify breaching confidentialty???
A property approach e.g. Data Protection Act, FOI
GMC standard - a breach of confidentiality is justified
only ‘ where failure to do so may expose the patient or others to
risk of death or serious harm’
Where possible gain the patient’s consent to inform
relatives.
Hope, Savulescu, Hendrik, Medical Ethics and Law (2008)
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Clinical Practice
1.
Consent
2.
Confidentiality
3.
Communication
Uncertainty of much of information / Realistic expectations /
Avoidance of exaggeration of genetic risk
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Genetic Information Non Discrimination
Act (GINA) 2008
The Genetic Information Non-discrimination Act of 2008
(GINA)
•
A law in the US designed to prohibit the improper use of genetic
information in health insurance and employment. It prohibits
group health plans and health insurers from denying coverage to
a healthy individual or charging that person higher premiums
based solely on a genetic predisposition to developing a disease
in the future. The legislation also bars employers from using
individuals’ genetic information when making hiring, firing, job
placement, or promotion decisions.
• ? The "first major new civil rights bill of the new century"
(Senator Ted Kennedy)
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Eugenics
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‘Eugenics casts a long shadow over
contemporary genetics.’1
1
Wikler (1999)
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Eugenics
•
•
•
•
Francis Galton, cousin of Darwin coined the term
and launched the movement, based on selective
breeding and applying the theories of natural
selection to the human population.
Eugenics [Greek] ‘Good Creation’
‘The use of science to improve the human
genome’
Extremely popular among scientists, doctors,
leaders of society (1880s – 1945).
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Eugenics
•
•
Galton believed that the talented and favoured of
society should be encouraged to have many
children (positive eugenics) and those with ‘less to
offer’ should be discouraged from reproducing
(negative eugenics). Strong eugenics movements in
many countries, inc. US, Canada, UK, Germany.
Adopted by the Nazis, imposed sterilisation and
mass murder; fell into disrepute from 1945.
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Eugenics
Now an offensive concept, but ‘is clinical genetics
simply eugenics under a different name?’1
Positive and Negative eugenics are distinct practices
motivated by distinct aims.
1Wikler,
JME 1999
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Negative
1
Eugenics
? Forms of negative eugenics - genetic testing and
screening, PIGD, gene therapy
Thus the aim of negative eugenics is to prevent or
limit / control disease
1Glannon,
Biomedical Ethics, OUP
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Positive
1
Eugenics
An example of positive eugenics might be genetic
enhancement i.e. improving normal traits and
capacities
1Glannon,
Biomedical Ethics, OUP
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1
Eugenics
‘If there is a decisive reason and thus an obligation to
prevent or control diseases, then we are obligated to
practice negative eugenics.’
‘If there is no decisive reason and thus no obligation to
improve normal capacities, then there is no obligation
to practice positive eugenics.’
Indeed should positive eugenics
be prohibited?
1Glannon,
Biomedical Ethics, OUP
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Gene Therapy
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Gene Therapy
Gene therapy is in its infancy.
Options – germline and somatic.
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Gene Therapy
•
•
•
•
Somatic
Uses genetic methods to treat disease in an
individual. Thus the treatment only affects the
targeted individual.
Aims to cure disease in the same way as other
disease treatment.
Risks as with all new therapies.
However ?future potential of enhancement of
human characteristics.
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Gene Therapy
Germline
The therapeutic intervention affects the targeted
individual, but also future generations by genetic
changes to the germline cells. Thus risks such as
cancer inducing genes, etc. may affect future
generations,...
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Cloning
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Cloning
Therapeutic
Reproductive
To harvest ES cells for therapy
To produce a new human being
Controversy as to whether therapeutic cloning should be allowed /
However most agree reproductive cloning should be prohibited
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Cloning
•
•
•
A cloned cell has a genome that is a near-identical copy
of the genome of its parent or ‘progenitor’ cell.
The 5 day old embryo is called a blastocyst and embryonic
stem (ES) cells can be derived from this and grown on in
culture to produce ES cell lines. These cells are totipotent
and have the ability to regenerate tissue. Hence the
potential to cure or alleviate diseases such as
Parkinson’s, diabetes, heart disease, etc.
2 methods of genome cloning – Fission vs. Fusion
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Therapeutic Cloning
Research in this area remains one of the most
dynamic in genetics with massive potential both
scientific and commercial.
2004 fraudulent claim by Korean scientist, Woo
Suk Hwang that his team had successfully cloned
a human embryo and derived a ES cell line from
it.
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Cloning
Cloning by fission
Blastocyst division
Twinning is induced in the blastocyst
by the application of heat or mechanical
stress. Splits in two, and the two halves
continue to grow into complete embryos.
Max. two identical embryos.
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Cloning
Cloning by fission
Blastomere separation
The coating of an early embryo
(blastocyst) is removed and the cells
(blastomeres) are placed in a
solution that separates them. Each
of these blastomeres is
undifferentiated and can grow into
an embryo. This technique can
produce eight embryos at most, but
can be repeated on each new
embryo to produce a larger number.
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Cloning
Cloning by fusion (SCNT)
Fusion is achieved through the process
of somatic cell nuclear transfer (SCNT).
The nucleus is removed from a somatic
cell and implanted into the cytoplasm of
a denucleated egg.
The egg reprograms the somatic cell’s
DNA to a totipotent state, so that a
complete embryo can be grown out of
this cell. A theoretically endless number
of clones can be created from the same
individual in this way.
Somatic cell
Enucleated Egg
SCNT is the only method currently
available that might be used to clone
existing or pre-existing people.
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Therapeutic Cloning
Centres on the concept of stem cells. Stem cells have the
ability to develop into different mature cell types.
Totipotent stem cells have the potential to form a complete
animal if placed in a uterus. They are early embryos.
Pluripotent stem cells are immature with the potential to
develop into any of the mature cell types in the adult
but cannot form a complete animal if placed in a
uterus.
This is regenerative medicine – ‘The holy grail’ of
medicine.
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Therapeutic Cloning
Hopes for
1.
2.
3.
4.
5.
6.
There is a shortage of tissue for transplantation
There are problems with the compatibility of tissue
transplanted from one individual to another, requiring
immunosuppressive drugs with severe side-effects. Whereas
cloned tissue from an individual would be compatible.
The role of transplantation might be expanded to include
heart attack and CVA
Cloning may prove cost-effective means of preventing
disability and morbidity, and of promoting distributive justice.
Research into disease and drug testing using ESC lines in the
lab.
Reduced need for animal experimentation.
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Cloning by (SCNT)
Possible future therapeutic application
e.g. Leukaemia
Enucleated Human
or Animal Egg
Skin cell
from
leukemic
patient
Blood stem cells
transferred post chemotx
Derive ESC line
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Objections to Therapeutic Cloning1
Objections to therapeutic cloning concern the morality of
creating a human embryo with the intention of
destroying it to harvest ES cells for research into future
therapies. This it is argued that it amounts to destroying
potential human life. In so far as the potential of an
embryo to become a human being gives it the right to
life, therapeutic cloning violates this life and thus should
be prohibited. Does the embryo have the same moral status as
a human being?
1Glannon,
Biomedical Ethics, OUP
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Objections to Therapeutic Cloning1
If an embryo has the same moral status as a person, then
embryo research, in vitro fertilisation (IVF) and any
termination of pregnancy is wrong.
In natural conception, for every new life, 5 embryos die
(Harris, 2000). We implicitly accept this is a price worth
paying in naturally conceiving a child, then is it not a
price worth paying to save an existing life.
1Hope,
Savulescu, Hendrik, Medical Ethics and Law (2008)
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Objections to Therapeutic Cloning1
A further objection to therapeutic cloning is the concern
that in creating human embryos to destroy them
represents a violation of the sanctity of life from
conception and thus should be prohibited.
The fact that therapeutic cloning blocks the embryo’s
potential to become an actual person, thus their right to
life is removed and so should be prohibited, even if
therapeutic cloning would benefit those existing people,
already alive, suffering from degenerative diseases, who
would benefit from future ESC therapies.
1Glannon,
Biomedical Ethics, OUP
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Objections to Therapeutic Cloning
SCNT requires a supply of fresh human eggs (unless
animal human hybrid research, using e.g. rabbit eggs,
becomes acceptable). These must be provided by
donation from women, who need to undergo arduous
and sometimes painful ovarian stimulation and egg
retrieval. Risk of OHSS. Egg donors may have
restricted autonomy, perhaps due to poor economic
circumstances, etc.
As a new technology, will this be available only for the
rich, while the egg supply may be provided by those less
well off, perhaps in developing countries.
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Support for Therapeutic Cloning1
Others argue that an embryo is merely a clump of not integrated
cells and cannot have interests and rights. Thus if an embryo
cannot have interests or rights, it cannot be harmed or wronged
by not becoming a person.
Thus objections to therapeutic cloning rest on the absolute claim
that embryos have a right to life which outweighs any potential
benefit to existing people. But while embryos cannot suffer from
or be harmed by not realizing their potential, existing people can
suffer from and be harmed by disease. These existing people
could benefit from treatments resulting from therapeutic cloning
research. Embryos cannot be harmed or wronged by being
created for this research.
1Glannon,
Biomedical Ethics, OUP
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Support for Therapeutic Cloning1
Sanctity of life
If it is argued that embryos embody sanctity of life, then
existing people also do. So it may be agreed that embryos
and people have equal moral status. Yet in terms of
suffering, embryos cannot suffer whereas existing people
can suffer. The combination of sanctity and suffering vs.
sanctity seems to carry more moral weight. If the suffering
of existing people is morally worse than the creation and
destruction of embryos then it follows, we should be more
concerned about this. If embryos cannot be harmed, then
therapeutic cloning should be permitted, i.e. we should do
more for the needs of existing people than for the putative
needs of merely potential people (embryos).
1Glannon,
Biomedical Ethics, OUP
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Other options?
Adult stem cells avoid this issue, but research has
shown them not be ‘as plastic’ as ES cells, in
terms of potential to generate as many cells
types. In addition they are likely to be more
immunogenic than ESC.
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Other options?
Human-animal hybrids
Cloning by SCNT
An enucleated animal
rather than human egg
is used and the human
somatic cell nuclear
material is inserted into
it, thus creating a
hybrid.
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Somatic cell
Animal (e.g. Rabbit)
Enucleated Egg
81
Other Options?
Human-Animal Hybrid / Chimera
Technology
Ethically these may be seen as unnatural and
crossing a moral line, but with close regulation
and destruction of the embryos following use,
and an understanding that this is the creation of
new biological tissue rather than new species
would this be morally more acceptable?
Risk of harm in future – Possibility of introducing
new infections (zoonoses) into the human
population.
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The Slippery Slope
Some would argue that while therapeutic cloning
might be morally permissible, it should be
prohibited as it could lead down the slippery slope
to reproductive cloning, which would not be
morally permissible.
‘? Throwing the baby out with the bath water’
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Reproductive Cloning
The production, by cloning, of an identical or near
identical genetic copy of an existing person or a person
who previously existed.
[Agricultural industry - e.g. cattle have been cloned in this way using
both fission and fusion.]
The Human Reproductive Cloning Act (2001) UK
- states that, ‘A person who places in a woman a human embryo
which has been created otherwise than by fertilisation is guilty of
an offence.’
Also an offence in many other countries and a number of
international declarations forbid it.
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Cloning
Cloning by fission
Blastocyst division
Twinning is induced in the blastocyst
by the application of heat or mechanical
stress. Splits in two, and the two halves
continue to grow into complete embryos.
Max. 2 identical embryos.
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Cloning
Cloning by fission
Blastomere separation
The coating of an early embryo
(blastocyst) is removed and the cells
(blastomeres) are placed in a
solution that separates them. Each
of these blastomeres is
undifferentiated and can grow into
an embryo. This technique can
produce 8 embryos at most, but can
be repeated on each new embryo to
produce a larger number.
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Cloning
Cloning by fusion (SCNT)
Fusion is achieved through the process
of somatic cell nuclear transfer (SCNT).
The nucleus is removed from a somatic
cell and implanted into the cytoplasm of
a denucleated egg.
The egg reprograms the somatic cell’s
DNA to a totipotent state, so that a
complete embryo can be grown out of
this cell. A theoretically endless number
of clones can be created from the same
individual in this way.
Somatic cell
Enucleated Egg
SCNT is the only method currently
available that might be used to clone
existing or pre-existing people.
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Arguments made in favour of reproductive cloning1
Reproductive cloning
Liberty
Medical reasons
Freedom of scientific inquiry
To achieve a sense of immortality
Eugenic selection
Treatment of infertility
Replacement of a dead relative
‘Clonism’ – a new form of discrimination
1Hope,
Savulescu, Hendrik,
Medical Ethics and Law (2008)
Clones are not the same person
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Arguments made against reproductive cloning1
Reproductive cloning
(But are twins an affront to human dignity?)
Liable to abuse, e.g. evil dictator
cloning armies or copies of self
Instrumentalisation of
human beings
Clones will live in the shadow
of the original person
Allows eugenic selection
But many current technologies
could also be used for eugenics, e.g. PIGD
Cloning would reduce
genetic variation
Right to genetic individuality
Safety
An affront to Human Dignity
1Hope,
Savulescu, Hendrik,
Medical Ethics and Law (2008)
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Reproductive Cloning
Concerns about cloning violating human dignity
are misguided because they concentrate too
much on the biology of our entry into the
world. We have human dignity because we are
persons with autonomous desires, beliefs, and
intentions that are not entirely functions of our
biology.
1Glannon,
Biomedical Ethics, OUP
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Reproductive Cloning1
Safety
Probably the strongest reason for banning it is that it
would result in harm to the cloned child. c.f. ‘Dolly’ the
sheep (b. 1996) aged at a faster rate than normal and
needed to be euthanized. Thus risk of premature aging
and disease (through mutations?).
So perhaps the only valid reason to ban reproductive
cloning is that it could result in physical harm to
individuals who might be cloned.
1Glannon,
Biomedical Ethics, OUP, Hope,
Savulescu, Hendrik, Medical Ethics and
Law (2008)
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Reproductive Cloning1
Cloning is in its infancy.
If however, reproductive cloning and other forms
of artificial reproduction were to become, in
time, safer and more efficient than natural
reproduction, would we have a moral duty to
promote these over natural methods of
reproduction?
1Hope,
Savulescu, Hendrik, Medical Ethics
and Law (2008)
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