title: Preimplantation genetic diagnosis: development and regulation.
abstract: Pre-implantation genetic diagnosis (PGD) is used to biopsy and analyse embryos created through in vitro fertilisation (IVF) to avoid implanting an embryo affected by a mutation or chromosomal abnormality associated with serious illness. It reduces the chance that the parents will be faced with a difficult decision of whether to terminate the pregnancy, if the disorder is detected during the course of gestation. PGD is widely accepted for this purpose although there have been suggestions that such procedures have the effect of de-valuing persons in the community with disabilities. PGD potentially has other more controversial purposes, including the selection of the sex of the baby for personal preferences such as balancing the family, rather than to avoid a sex-linked disorder. Recently PGD has become available to create a donor child who is Human Leukocyte Antigen (HLA) matched with a sibling in need of stem cell transplant. In most cases the intention is to utilise the cord blood. However, an HLA-matched child could potentially be required to be a donor of tissues and organs throughout life. This may arise should the initial cord blood donation fail for any one of several reasons, such as inadequate cord blood cell dose, graft failure after cord blood transplant, or the recipient child experiencing a recurrence of the original illness after transplant. However, such on-going demands could also arise if a HLA-matched child was fortuitously conceived by natural means. As such, the issue is not PGD, but rather whether to harvest bone marrow or a solid organ from a child. This raises the question of whether there should be limits and procedures to protect such children from exploitation until they achieve sufficient competence to be able to make mature and autonomous decisions about whether to donate, even if the consequence may in some cases be that it is too late to save the sibling. Additionally, the parents may not be able to make a dispassionate decision, when they have a conflict of interests between their children. As such, parents may not be the best proxy decision-makers in this area and the decision might be better made by an independent authority or court. This paper considers ethical and legal issues arising from PGD. It will compare the willingness of the HFEA in the United Kingdom to allow this process to be used even in cases where the condition suffered by the sibling is non-heritable, with the more restrictive guidelines in New Zealand and questions the constitutional basis on which ethics committees develop policy in the absence of a legislative framework.
authors.affiliation: New Zealand Bioethics Council.
authors.forename: C
authors.initials: C
authors.lastname: Thomas
mesh_terms: D017041:Ethics Committees; D030342:Genetic Diseases, Inborn / Q000175:diagnosis; D033161:Government Regulation; D006801:Humans; D007883:Legislation, Medical; D019836:Preimplantation Diagnosis / Q000941:ethics*; D012743:Sex Preselection / Q000941:ethics