C2.7 -- Bioethics

Question 1

Explain how the use of iPSCs may overcome some of the ethical concerns of using other types of
stem cells in medical research and treatment. [2]

Answer 1

1. As iPS cells are not from an embryo, there will be no destruction of embryos and hence not regarded as killing a life due to
   some views that embryos are viable living organisms;
   B. Some object to extracting stem cells from an embryo to make replacement body cells is
   treating embryo as just a source of spare parts;
   C. Once human status is denied to embryos, this precedent may extend to other categories
   of human beings such as profoundly disabled or elderly infirm;
2. Since the patient’s own iPSCs can be used, there will be no foreign tissues or antigens
   introduced into the patient and thus will not result in immune response/tissue rejection and
   thus there will be no need for immunosuppressant drugs;

Question 2

Comment on the ethical aspects of this new therapy. [2]

Answer 2

1. Unforeseen circumstances from T cells lacking CCR5 / immune response might be affected
   if T cells do not have CCR5 receptor;
2. Unintended changes in DNA as a result of gene editing may contribute to development of
   cancer;
3. Blood stem cells are multipotent and hence cannot form a whole organism, hence no debate
   of whether or not a life is “sacrificed”;
4. Potential to cure patients completely so patients no longer have to be on lifetime anti-viral
   therapy;
5. AVP eg. Accessibility to treatment

Question 3

In a blood transfusion, blood from a donor is transferred into the veins of a recipient patient. Before transfusion, blood is tested in various ways to ensure that it is:
safe for transfusion to any recipient.
safe for transfusion to the specific recipient.
Explain how physiological problems may develop in the recipient as a result of receiving blood that has not been tested in either of these ways. [10]

Answer 3

Blood needs to be tested to ensure safety for any recipient by checking that it is
does not contain microorganisms / pathogens, such as bacteria and viruses;
Transfusion of blood containing bacteria or viruses to recipient would cause
infections in the recipient;
Blood also needs to be tested as safe for the specific recipient by matching the blood
type;
The ABO blood group in humans is controlled by a gene locus I with 3 alleles: IA, IB
and Io, resulting in 4 possible blood groups: A, B, AB and O;
Red blood cells can contain antigen A and/or antigen B based on the blood group of
the individual;
Blood group A individuals express antigen A, blood group B individuals express
antigen B, blood group AB individuals express both antigens A and B, and blood group O individuals do not express antigens A or B;
(description of each blood group and their respective antigens)
Individuals will produce antibodies against non-self antigens;
Blood group A individuals produce antibodies against antigen B, blood group B
individuals produce antibodies against antigen A, blood group AB individuals do not produce antibodies against antigens A and B, and blood group O individuals produce antibodies against both antigens A and B;
(description of each blood group and the antibodies produced)
If matching of blood group was not done, recipients could be given incompatible blood. The red blood cells in the transfused blood could be recognised by the recipient’s antibodies and destroyed/lysed;
10.Recipient would hence not benefit from the blood transfused – there is still insufficient red blood cells to transport oxygen in the recipient;
11. When an immune response is mounted against the transfused blood, inflammatory responses are also induced, contributing to fever and pain in the recipient;
12. AVP: ref to other antigens eg. rhesus factor; QWC: must address both bullet points

Question 4

Discuss the social and ethical considerations for the use of gene therapy. [5]

Answer 4

1. There is the fear of genetic discrimination by society because gene therapy could be used
   for treatment of diseases or enhancement of desired traits not associated with disease;
   a. Ethical concerns in pursuing genetic enhancement including increased social
   inequality and a lowered tolerance for human diversity
2. As gene therapy treatment is exorbitantly expensive, there may be discrimination against
   the poor who cannot afford the treatment;
3. Religious group may view gene therapy as tampering with nature and going against the
   natural way of life;
4. Arguments against germline gene therapy:
   a. It is difficult to follow patients in long-term clinical research. Gene therapy patients
   would need to be under surveillance for decades to monitor the long-term effects
   of the therapy on future generations.
   b. Point 1
   c. Because germ-line gene therapy involves research on early embryos and affects
   their offspring, it essentially creates generations of unconsenting research subjects
   (Not for this qns) Arguments in favor of gene therapy:
   - Potential for treating desperately ill patients or preventing the onset of terrible illness.
   Where conventional treatment has failed, gene therapy may offer the only effective
   way to treat such patients.
   - Somatic-cell gene therapy corrects or alleviates the genetic defect present in the
   individual alone, without impacting the genetic information transmitted to the next
   generation.
   - Arguments for germline gene therapy:
   d. It offers a true cure, and not simply palliative or symptomatic treatment
   e. It may be the only effective way of addressing some genetic diseases, e.g. for
   diseases that affect an extensive or inaccessible area of the body like the nervous
   system such as neurodegenerative diseases. T least the next generation need not
   suffer from the same fate as the parent.

f. By preventing the transmission of disease genes, the expense and risk of somatic-
cell therapy for multiple generations are avoided.

g. Prospective parents at risk for transmitting serious genetic diseases have an option
of having normal children where previously they would simply refrain from having
children for fear of passing on the disease.

Question 5

14. Discuss the ethical and social implications of genetically modified organisms. [6]

Answer 5

Social implications
1. Transfer of antibiotic resistance markers to pathogenic microorganisms which may result
in increase in resistance to clinically important antibiotics;
2. Probability of introducing novel allergens as GM foods may contain proteins introduced
from sources people are allergic to;
3. Possibility of GM food being toxic or carcinogenic as they may cause over-expression of
other proteins;
4. Monopolistic behaviour of biotechnology companies as terminator gene is likely to be
inserted into many GMO seeds, causing second generation seeds to be sterile;
5. Scientists have raised concerns about innovations in research that are not shared, raising
fears that world food production may be dominated by a few large biotechnology
companies;
6. Increasing dependence of developing nations on industrialized nations;
7. Impact on international trade as Europe has been much more hesitant than the United
States in accepting GM products in processed food;
Ethical issues
8. Tampering with nature as it is going against the natural way of life;
9. Lack of mandatory food labelling in some countries;
10. Religious groups are concerned that GM foods might contain genes from animals
prohibited by their religion;