Review of preimplantation tissue typing
Preimplantation tissue typing is a technique which allows for the selection of embryos in order to bring about the birth of a child who can provide a matched tissue donation to an existing sibling. It is also sometimes called HLA tissue typing.
The first reported use of preimplantation tissue typing was in 2000 in the United States, when preimplantation genetic diagnosis (PGD) and preimplantation tissue typing was used to avoid the birth of a baby with an inherited condition and whose cord blood could also be used in a tissue donation to an existing sibling with the same condition.
Following detailed consideration by the HFEA’s Ethics Committee the HFEA produced an interim policy on preimplantation tissue typing in November 2001.This policy approved, in principle, the licensing of PGD with tissue typing.
In 2004, after a period of public and professional discussion, the HFEA took the decision to review the interim policy.
The review was conducted by the Authority’s Ethics and Law Committee (ELC), who researched the scientific and clinical developments, expert views on cord blood and bone marrow transplantation, legal developments, academic literature and public attitudes.
Research conducted in the course of the review included:
- consideration by the Scientific & Clinical Advances Group of the latest evidence relating to the risks associated with blastomere biopsy and implications for the resulting child
- expert psychosocial evidence and literature review concerning the experience of families and children in sibling cord blood and bone marrow donation
- expert evidence and literature review concerning current practice in cord blood and bone marrow donation for a range of conditions
- research into case law relating to consent and authorisation for procedures involving minors
- review of statements and opinions of UK, foreign and international ethics and advisory bodies relating to preimplantation tissue typing
- commissioned research into public opinion on issues related to embryo selection for tissue type and sibling cord blood and bone marrow donation.
The findings of the research indicated that preimplantation tissue typing was not necessarily an undesirable use of technology.
During its meeting in July 2004 The Authority considered the findings of the review on preimplantation tissue typing and agreed a revised policy.
The policy continued to allow for preimplantation tissue typing to be used only where there was an existing child affected by a serious or life-threatening condition and where all other possible treatments had been explored and discounted.
Applications would continue to be considered by the HFEA on a case-by-case basis.
The new guidance differed from the policy position established in November 2001 in the following principal respects:
- the new guidance recognised that preimplantation tissue typing may be acceptable in cases in which the embryo to be tested was not itself at risk from the condition affecting the existing child
- depending on the indications for the existing child, it may be acceptable to use preimplantation tissue typing with a view to using bone marrow from the resulting child
- detailed guidance relating to clinical decision making and patient information was be included.
The HFEA is currently carrying out an evaluation of the licensing of HLA tissue typing applications and evaluation of the licensing of ‘later onset’ and ‘lower penetrance’ conditions.
As part of the evaluation the HFEA will gather evidence concerning how the HLA tissue typing policy has operated in licensing decisions made since 2001, and the impact of this on clinicians and patients.
- 21-07-04: HFEA agrees to extend policy on tissue typing
- 08-04-03: Court of Appeal allows tissue typing for human embryos under strict conditions
- 01-08-02: HFEA confirms that HLA tissue typing may only take place when PGD is required to avoid a serious genetic disorder
- 13-12-01: HFEA to allow tissue typing in conjunction with preimplantation genetic diagnosis
- 13-03-09: HFEA to allow tissue typing in conjunction with preimplantation genetic diagnosis
- 12-03-09: CORE Judicial review on PGD with tissue typing
Page last updated: 11 January 2012