Ethics in Genetics Associate Professor Martin Delatycki Director Bruce Lefroy Centre Murdoch Childrens Research Institute Consultant Clinical Geneticist Genetic Health Services Victoria
Largest paediatric research institute in the Southern Hemisphere
60 research groups in 6 themes
Located at the Royal Children’s Hospital
Bruce Lefroy Centre
Research into neurogenetic diseases (Friedreich ataxia, Parkinson disease, Huntington disease, dystonia)
Community genetic research (haemochromatosis, cystic fibrosis, Tay Sachs disease)
Genetic ethics research
THE HIPPOCRATIC OATH
I swear … the following Oath: To consider dear to me as my parents him who taught me this art …….
I will prescribe regimen for the good of my patients according to my ability and my judgment and never do harm to anyone. To please no one will I prescribe a deadly drug, nor give advice which may cause his death. Nor will I give a woman a pessary to procure abortion. …... In every house where I come I will enter only for the good of my patients, keeping myself far from all intentional ill-doing and all seduction……….... All that may come to my knowledge in the exercise of my profession ………... which ought not to be spread abroad, I will keep secret and will never reveal. If I keep this oath faithfully, may I enjoy my life and practice my art, respected by all men and in all times; but if I swerve from it or violate it, may the reverse be my lot.
A bility to make decisions for oneself on the basis of deliberation
Acting so as to benefit others
Not harming others
Moral obligation of fairness.
Treating people equally in relation to criteria acknowledged to be morally relevant.
Great variability in different societies, cultures and religions
In 2008 what has changed?
Options of genetic testing provide new choices
the type of children we have
information (management ) - future health
Doctor patient relationship in genetics
gene affects the family; who is the patient
Duty of care ----> ?duty to warn
confidentiality/disclosure measured by the greatest potential harm
1:2 Chance of the condition in child of affected parent
Traditional prenatal diagnosis
Chorionic villus sampling
Preimplantation genetic diagnosis
Chorion Villous Sampling CVS
Preimplantation Genetic Diagnosis- PGD
In the context of IVF
Testing by embryo biopsy
Selected single gene disorders
Most common reason an objection to TOP or previous TOP following PND.
No apparent increase in birth defects
PGD - DNA extracted and mutation detection testing done
Method of embryo biopsy
The hole in the zona allows entry of a micro pipette to aspirate 1 or 2 cells from the embryo.
The cell can then be fixed to a slide, or placed in solution to allow genetic analysis.
PGD for single gene disorders
Requested by couples wishing to avoid TOP
97% diagnostic accuracy
20% pregnancy rate per cycle
Cystic fibrosis most common indication
Counselling by both Genetics and IVF team
Alan and his partner Helen are both deaf and they are planning to have children.
Alan has severe deafness as do both his father and his paternal grandfather. He grew up surrounded by deaf people.
Genetic testing has shown that Alan’s deafness is due to an autosomal dominant mutation.
Helen is the first in her family with deafness and this was thought to be due to exposure to a drug as baby.
The couple communicate by sign language
They come to you seeking prenatal diagnosis. They know that there is a 50% chance for each child to be deaf based on the dominant mutation found in Alan.
They state that they want their children to be deaf like them so they can experience the D/deaf culture they live in. They request prenatal or preimplantation genetic diagnosis with selection for deafness.
Can you help them?
Pre-implantation selection for deafness - the views of hearing children of deaf adults Cara Mand Martin Delatycki Rony Duncan Lynn Gillam
Duchesneau and McCullough deaf lesbian couple
Wanted a deaf child
“ Congenital deafness is precisely the sort of condition that disqualifies would be donors (Spriggs 2002)”
Sperm from friend with 5 generations of deafness
“ a hearing baby would be a blessing. A deaf baby would be a special blessing”
“… Deaf people like being deaf, want to be deaf, and are proud of their deafness… they claim the right to personal diversity, which is something to be cherished rather than fixed or erased” (Tucker 1998)
Current debate / controversy
Against selection for deafness…
selecting deafness = denying the child of an open future
“ We’d like to be able to hear our children and grandchildren laugh and cry, listen to the radio… the list is endless. Why would any human being want to deny such pleasure to herself or her children?” (Tucker 1998)
For selection for deafness…
Deafness not a disability
Their choice to make
Often (but not always):
Geneticists/ genetic counsellors
“ Deaf people are disabled more by their transactions with the hearing world than by the pathology of their hearing impairment” (Munzo-Baell 2000)
To gain insight into the attitudes of hearing children of deaf adults, to selection for deafness
Already know the views of both the hearing and Deaf community towards selection for deafness
Hearing children of deaf adults
Ideally placed, experience in both hearing and deaf world
2 Stage process, adopting qualitative and quantitative research methods
1st: individuals from CODA and health professionals. Semi-structured interviews. Answers analysed and used to compile a survey for second group of participants .
2nd: Anonymous survey broadcast electronically. Answers explored and similarities extracted and analysed.
Through CODA (worldwide organisation)
Deafness as a Disability vs. Culture
Onset on average in 40’s (4-80)
Death on average 15 years from onset
Chorea, dementia, personality change
No treatment known to change outcome
Autosomal dominant- all due to one mutation
Max has a family history of Huntington disease. He has predictive testing that shows that he has inherited the condition.
Max has two children- Ben is 8 and Nancy is 6. He requests that they be tested- do you test the children?
Genetic Testing of Children
To make diagnosis- uncontroversial (eg: Duchenne muscular dystrophy)
Where preventative treatment in childhood is proven- relatively uncontroversial
Where no treatment is available and onset is adulthood- predictive testing- controversial
Predictive Genetic Testing of Children
Genetic societies- should not do so as it removes the right of that person to make their own decision
Most adults choose NOT to have this testing
The child may be treated differently to their detriment if their genetic status is known
Predictive Genetic Testing of Children
Alternate view eg: Prof Julian Savulescu-
Knowing status from childhood will allow that person to grow up with the knowledge of their genetic status and adjust to this
Following studies by Rony Duncan, Martin Delatycki, Bob Williamson, Julian Savulescu, Lynn Gillam
Clinical Geneticist Survey
Web-based survey sent to:
- Members of the Australasian Association of Clinical Geneticists (98)
- Members of the Clinical Genetics Society of the UK (400)
- All Medical Doctors who are members of the American Society of Human Genetics (1732)
The target was Clinical Geneticists
Responses were received as anonymous e-mails
22 Tests in Immature Minors
27 Tests in Mature Minors
18/27 some follow-up
2 adverse events
“ Initial depression and rebellion but eventual acceptance” HD +ve 17 year male
“ No psychological disturbance but worry and responsibility for affected mother and untested brothers” HD -ve 17 year female
9 reports of benefits
? Agree with Guidelines
The majority of respondents agree with the existing guidelines, but feel that each case needs to be assessed individually
Views on existing guidelines
47% strongly agree
3% don’t know
2% strongly disagree
Views on existing guidelines
A strong theme of ‘each case must be assessed on its own merits’
“ I support informed consent for testing and some minors are capable of providing it, others are not”
“ I don’t believe in a rigid cut-off age … as I believe obtaining maturity to gain informed consent is a gradual process”
“ Occasionally there are exceptions to the age limit and one has to be flexible”
Interviews with Young People
18 interviews with young people who had undergone predictive genetic tests
8 young people who were tested for HD
2 gene-positive & 6 gene-negative
Tested between ages of 17 and 25 yrs
“ I’m a very pessimistic person, I was always saying it’s going to be positive, it’s going to be positive… it wouldn’t have been so much of a shock because I’ve sort of said to myself, you know, I’m going to be positive anyway” Travis:M:24:HD:20:-ve
“ Knowing that there’s a 50:50 chance, it’s just, like it’s always in your head that yes I have it, rather than no I don’t have it” Zach:M:26:HD:23:-ve
“ I just thought I had it, obviously I didn’t have signs or anything, but like, in my head, yeah”
“ I’ve gotten off drugs since I found out”
“ Since I’ve been tested I’ve been pretty good… I haven’t been in trouble with the police or anything… I seem to have changed a bit, just come out of me shell.. You know.. A bit happier and stuff… I want to start me own business” Troy:M:26:HD:25:-ve
“ I thought well, if I can go through this whole process of getting tested for this thing, I can pretty much do anything… I respected myself a lot more for that”
“ It stopped me from living effectively at the time, I mean, I did the day to day things, I went to school, I ate dinner… but, didn’t feel like I was living kind of thing, like I had a life but I wasn’t living. Once I had the knowledge, that was it, ok, fine, you know… knowing but not knowing in a way… knowing that if I live long enough I will develop symptoms one day, um, but now knowing exactly what the rest of my life has in store for me and allowing me just to accept that and just live.” Belinda:F:25:HD:21:+ve
Holding Your Breath
“ All my life I thought I was going to get this illness, all my life, and last year I found out I didn’t, you know, so for 19 years it feels like I’ve held my breath, thinking that I’m going to get this illness, and now it feels like I’m a newborn child, you know, like, I can live a life I never knew I could. It seems really weird to adjust to, like, the whole time I thought I was going to get it and then she told me I didn’t have the gene… and I felt like I could breathe for the first time in 19 years”
Sonya requests prenatal diagnosis (PND) for HD as her partner Colin is at 50% risk
Colin has stated that he does not wish to know his HD status and he would suicide if he found he had the mutation
Sonya says if the PND is positive she would tell Colin she miscarried