Genetic Choices

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Genetic Choices
Questions from the text (p460):
Should genetic testing be done even when no treatment is available?
Do carriers of deadly, inheritable disease have a duty to warn their
children?
Is it “playing God” to alter genes to treat diseases or keep them from
affecting future generations?
Is it wrong to use preconception genetic testing and embryo selection
to avoid disabled children?
Is such discriminatory against the disabled?
Is choosing eye color, gender, musical v. athletic ability, etc., wrong?
Is eugenics wrong (trying to make society free of genetic disease)?
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Genes and Genomes
Read p460-461 … Vaughn’s discussion of the
science of genetics in “Genes and
Genomes”
Is the whole discussion ideologically
confused?
“Genes have their say, but not necessarily the
final say, on how a person turns out, for
he or she is also affected by the incredibly
complex interactions between genetic
systems and environmental factors”
What else plays a role in “how a person turns
out”?
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Genes and Genomes
More opportunity for confusion:
There is a long discussion of “errors” in the human genome, p461, right
hand column:

“flaws in the system”
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“Mistakes (mutations or alterations)”
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“genetic errors”

“4,000 hereditary diseases”

“relation between genetic flaws and genetic disease … anything but
simple”
What ideological commitments, opposite of the earlier ideological
commitment, present in this language will affect how we view the
rightness or wrongness of genetic choices?
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Types of Genetic Testing
Newborn Screening

every state mandates some genetic testing for newborns

first mandatory genetic test (some states screen for 30 disorders) was for phenylketonuria
(PKU), which causes severe retardation when not treated early with special diet
Carrier Testing

not mandated

autosomal dominant disorders (just one parent can pass the disorder to offspring) …
Huntington’s is an autosomal dominant disorder

autosomal recessive disorders (both parents must carry the disorder to pass it to offspring) …
Cystic Fibrosis is an autosomal recessive disorder
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Types of Genetic Testing
Predictive testing

will you develop a genetic disease later in life?

some genetic tests are guarantees of disease (Huntington’s disease,
which means early dementia and physical deterioration, then death)

some are simply likelihood (Venous Thrombosis … a blood-clotting
disorder)
Diagnostic testing

to determine if someone with symptoms has a genetic disorder
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Types of Genetic Testing
Prenatal testing (testing for the health of a fetus)
Common prenatal testing methods:
1.
2.
amniocentesis
chorionic villus sampling (testing of placental cells)
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Downs Syndrome
Sickle Cell Anemia
Tay-Sachs disease
General developmental disorders, blindness, deafness, etc.
Preimplantation genetic diagnosis (PGD)

testing embryos produced through IVF before they are implanted (or before
they become embryos, per the definition from Abortion chapter, p255)
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Personal Knowledge
When, if ever, should someone feel obliged to do a genetic test for themselves?

Huntington’s causes death in middle age (40s-50)

Would you want to know if you had it?
Vaughn uses the case of Maria to illustrate how things change when others are
involved:
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Maria has Wilson’s disease
Wilsons causes liver dysfunction and serious psychiatric problems
Effective treatment works if caught before symptoms appear
Maria is ashamed of her psychiatric symptoms and doesn’t want to tell her
siblings
Her siblings, however, have a 25% chance of having Wilson’s themselves
What should Maria do?

Autonomy says that Maria’s wish for privacy should be respected

But she seems to have a duty to warn her siblings
Confusingly, Vaughn casts the question as one of competing duties. Read it,
column 1, p465
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Paternalism, Autonomy,
and Confidentiality
Maria’s case takes on a new dimension when a healthcare provider enters
the equation

If Maria insists on confidentiality, what would you do?

What is a Tarasoff duty again?
Vaughn claims that “law has been equivocal,” p465, top
Most ethicists endorse a principle of proportionality, or proportionate
reasons:

As harm increases in severity and likelihood, confidentiality’s value
decreases
The major conflicting concern here is harm to the healthcare profession;
providers do not want patients to avoid health knowledge for fear of
having it exposed
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Paternalism, Autonomy,
and Confidentiality
Autonomy v. Paternalism issues arise
when testing accidently reveals a
genetic disorder that is
unpreventable, untreatable
Should a physician tell a patient of the
discovery that Alzheimer's is in
their future?
What considerations can you think of in
favor of Paternalism?
What of Autonomy?
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Paternalism, Autonomy,
and Confidentiality
The more genetic information is
available, the more opportunity
there is for employers and
insurance providers to learn of it
and discriminate against those
with genetic disorders
Is there a general duty of physicians
to make genetic information
hard to acquire?
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Reproductive Decisions
The problem of potentiality reappears:
Is it wrong to prevent a genetic disease by preventing the existence of
the person who will have it?
Dan Brock (top of p467), argues that
it would not be better for the person with the handicap to have it
prevented since that can only be done by preventing him from
ever having existed at all
This is called the ‘incoherence argument’ against genetic testing used
to keep those with genetic diseases from coming to be
Specifically the incoherence seems to be the idea of benefitting
someone by preventing their existence
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Reproductive Decisions
The natural response to the incoherence argument would be, we
can suppose, the ‘incoherence of the incoherence argument’:
Potential people don’t exist to be deprived of anything
Does that work?
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Reproductive Decisions
Discrimination against the disabled
Would genetic testing to prevent birth
defects be morally similar to Nazilike efforts to “eradicate whole races
of people”?
Is it inherently disrespectful to disabled
people to wish for a world where
there aren’t any such people?
If you think it is right to eliminate birth
defects and genetic diseases, what do
you say to this argument?
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Gene Therapy and
Stem Cell Research
Read about Gene Therapy (p468) and Stem Cell Research (p471)
on your own
Look at the Applying Major Theories discussion (p474)
Look at the Case Studies … they’re interesting
Do you accept the distinction between repairing problems
(okay), and enhancing individuals (not okay)? Why?
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