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The Ethics of Genetics

The Ethics of Genetics. Lecture 1 January 20th 2010 Dr. Ruth Pilkington.

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The Ethics of Genetics

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  1. The Ethics of Genetics Lecture 1 January 20th 2010 Dr. Ruth Pilkington Medical Ethics Year 2

  2. 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) Medical Ethics Year 2

  3. 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) Medical Ethics Year 2

  4. MonogenicOnly a small number of diseases Polygenic Number of gene mutations, e.g. cancer Multifactorial Most diseases Medical Ethics Year 2

  5. Monogenic disordersSingle gene mutation / Rarely complete penetrance Medical Ethics Year 2

  6. 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. Medical Ethics Year 2

  7. Genetic Testing& Screening Medical Ethics Year 2

  8. 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. Medical Ethics Year 2

  9. 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 non-monogenic disease). • Dangers – Insurers or employers might discriminate against individuals on the basis of the genetic information. 1Glannon, Biomedical Ethics, OUP Medical Ethics Year 2

  10. 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 Medical Ethics Year 2

  11. 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? Medical Ethics Year 2

  12. Considerations of Harm Is there a role for Society? Education... Is there a role for the law? Legal measures... Medical Ethics Year 2

  13. 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. Medical Ethics Year 2

  14. Huntington’s DiseaseConsiderations 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 obligationon 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 Medical Ethics Year 2

  15. Familial Breast CancerConsiderations 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 Medical Ethics Year 2

  16. Genetic Screening Medical Ethics Year 2

  17. 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 Medical Ethics Year 2

  18. 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 Medical Ethics Year 2

  19. 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 Medical Ethics Year 2

  20. Genetic Testing Medical Ethics Year 2

  21. 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? Medical Ethics Year 2

  22. Genetic testing Cases Medical Ethics Year 2

  23. Case 11 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) Medical Ethics Year 2

  24. Case 11 Molecular analysis of blood samples shows that Colm is not the biological father. ? Should the geneticist disclose the finding of non-paternity 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) Medical Ethics Year 2

  25. Case 11 ‘Options’ White lie’ to Colm and Truth to Anna (anecdotal evidence) 1 Adapted from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008) Medical Ethics Year 2

  26. Case 11 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) Medical Ethics Year 2

  27. Case 21 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) Medical Ethics Year 2

  28. Case 21 ? Should the doctor breach the patient’s confidentiality here. 1 Adapted from Hope, Savulescu, Hendrik, Medical Ethics and Law (2008) Medical Ethics Year 2

  29. Case 21 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) Medical Ethics Year 2

  30. Case 31 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) Medical Ethics Year 2

  31. Case 31 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) Medical Ethics Year 2

  32. Case 31 Personal Account Model Consider if harm to Niamh and her foetus is sufficiently severe to justify a breach of confidentiality- • Would termination of the pregnancy be a greater harm. • Would the harm of having DMD and not preventing it be worse. • Existing with DMD vs. not existing at all Adapted, Parker & Lucassen (1994), as quoted in Hope, Savulescu, Hendrik, Medical Ethics and Law (2008) Medical Ethics Year 2

  33. 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) Medical Ethics Year 2

  34. Genetic Testing of Children Medical Ethics Year 2

  35. 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) Medical Ethics Year 2

  36. 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) Medical Ethics Year 2

  37. 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) Medical Ethics Year 2

  38. Incompetent Adults Testing may amount to battery in law. Medical Ethics Year 2

  39. Genetic Counselling Medical Ethics Year 2

  40. 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) Medical Ethics Year 2

  41. Non-directive Counsellingis 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) Medical Ethics Year 2

  42. 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) Medical Ethics Year 2

  43. 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) Medical Ethics Year 2

  44. Non-directive Counselling However is the non-directive approach always the correct one? Medical Ethics Year 2

  45. Non-directive CounsellingSéan’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) Medical Ethics Year 2

  46. Non-directive CounsellingSéan’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) Medical Ethics Year 2

  47. Genetic Information & The Law Medical Ethics Year 2

  48. 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. Medical Ethics Year 2

  49. 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) Medical Ethics Year 2

  50. Clinical Practice • Consent • Confidentiality • Communication Uncertainty of much of information / Realistic expectations / Avoidance of exaggeration of genetic risk Medical Ethics Year 2

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