Pre-Implantation GeneticsPriyanca Patel and James Fox

What is pre-implantation genetic diagnosis (PGD)?

PGD enables people with an inheritable condition in their family to avoid passing it on to their children. It involves checking the genes and/or chromosomes of embryos created through IVF

Which act governs PGD and what are the key elements of this act?

Human Fertilisation and Embryology Act 2008

- It is unlawful to store or use gametes EXCEPT with a licence granted by the HFEA

- Need to give appropriate counselling (inc. Specific info about donated gametes)

- Requirement to consider the welfare of any child born as a result of treatment, and of any child that may be affected by the birth

- Specification of who is legally recognised as the mother and father of any child created by IVF

- Prohibition of the preferential use of gametes or embryos that carry a gene, chromosome or mitochondrial abnormality (or are of a particular sex associated with an abnormality) involving a significant risk that a person having that abnormality would have or develop a serious physical or mental disability, a serious illness, or any other serious medical condition

What does the Human Fertilisation and Embryology Act permit testing for?

Establishing whether the embryo has an abnormality that will reduce the risk of a live birth

Where there is a risk that the embryo will have an abnormality that will result in a serious disability or illness

Where there is a risk of gender related abnormalities that will result in a serious disability or illness sex selection is permitted (eg. Duchenne Muscular Dystrophy in males)

In order to determine whether an embryo is tissue compatible with a sibling who has a serious medical condition which could be treated with umbilical cord blood, bone marrow or other tissue of any resulting child (saviour sibling) NB: whole organs are NOT permitted under the definition of tissue

What ethical values and principals are involved in PGD?

Respect for PARENTAL autonomy Right to procreate? Right to choose further child? Right to make choices to benefit other children?

Your Duty as a DoctorDuty of CARE

Minimising harm Balancing benefits and risks Harm benefit ration- to whom?

Parents? Future child? Existing child(ren)?

How do we define harm? Physical harm? Psychological harm?

The wider communitySocietal values

Fair use of resources (principle of justice) Impact of IVF on funding (setting limits/criteria) Impact on PIGD funding (setting limits/criteria)

Limits on individual autonomy Harm to others (selection for abnormal genes) Discrimination (effect of societies view on

specific groups eg. Those with a disability) Respect for persons/human life

Groupwork Scenarios

Mr. and Mrs. Day are interested in PGD to ensure that their future children are deaf. They have agonized over the issue of family planning for several years, including lengthy discussions with their pastor and a counsellor. Their conclusion was that having a hearing child would inexorably alter their way of life and they fear that this child would eventually become estranged from them. They are also concerned that the distractions imposed on a hearing child by oral speech would interfere with their child's ability to communicate fluently in British Sign Language, the only language they share. Although they have considered adoption, they feel strongly that having at least one child together is important. Both were raised to believe, and strongly agree, that prenatal diagnosis of a foetus followed by termination of the pregnancy if the child was hearing is a morally unacceptable alternative.           

Mr. and Mrs. Day ask their family physician and the specialists at the Reproductive Specialty Clinic to help them conceive a child who will not be disadvantaged in learning their language and in developing social skills and personal relationships among their peers; they fear that a hearing child would be ostracized by their culture. 

M was born with a rare, incurable genetic condition called Fanconi anaemia, which rendered her body unable to produce enough blood cells. M’s best and likely only chance of survival was to find a bone marrow donor. The best bone marrow match is typically with a sibling, but M was an only child. Mr and Mrs N had always wanted to have more children, but, because Fanconi anaemia is an inherited condition, they knew that any future children also had a chance of getting the disease, for which Mr and Mrs N were carriers. Eventually, the Mr and Mrs N underwent IVF followed by PGD to choose an embryo that would have HLA genes that matched M and that would be free of Fanconi anaemia. After four IVF attempts, Mrs N gave birth to a baby boy, A. A’s placenta was gathered and all the cord blood saved. M started chemotherapy to destroy her bone marrow and received a transfusion of the cord blood cells a month later. The transplant cured M’s bone marrow failure but she still suffers from Fanconi anaemia and visits the doctors 35-40times a year to screen for solid-tumour cancers. A common cold could have dire consequences, but her bone marrow is functioning normally

Groupwork Scenarios

Thank you for listening… any questions?http://www.hfea.gov.uk/preimplantation-

genetic-diagnosis.html