Biotechnology companies and other supporters of stem-cell research have been left distinctly underwhelmed by claimed government concessions on the use of hybrid embryos as a source of stem cells.

The government’s stance on hybrid embryos, set out in the Human Tissues and Embryos (Draft) Bill issued last week, has changed little from when it published a White Paper including a general prohibition on hybrids in December 2006. This is despite claims by Public Health Minister Caroline Flint that the government was swayed by the opinions of the House of Commons Science and Technology Committee on the issue.

While the government has accepted in principle that creating “interspecies embryos” (hybrids and chimeras) is necessary and acceptable for research purposes, this language appears only in the introduction to the draft legislation. The bill itself – in Clause 17 (2) – merely confirms the general prohibition on interspecies embryos “except in pursuance of a licence”, then lists the conditions under which such a licence would operate (e.g., a standard 14-day limit on developing hybrid embryos, a ban on inserting these embryos into women or animals).

Further opportunity for lobbying

The research community can take some comfort, though, from the government’s request that a pre-legislative Parliamentary Select Committee consider whether specific regulations are needed to sanction exceptional use of hybrid embryos for research purposes, subject to licensing by the Human Fertilisation and Embryology Authority and, eventually, the proposed new Regulatory Authority for Tissue and Embryos. This will give the hybrid-embryo lobby an opportunity to put its case forcefully for exceptional use to be included in the main body of the legislation.

As the Department of Health notes in its preamble to the draft bill, last December’s White Paper “proposed that the creation of hybrid and chimera embryos in vitro should not be permitted but that there should be a regulation-making power allowing exceptions to this prohibition”. The bill as currently drafted “reflects this position”, it adds.

In January this year the HFEA decided not to rule on licence applications for research proposals using hybrid embryos from teams at King’s College London and Newcastle University until there had been a “full a proper public debate” on the issue. The Authority launched a public consultation last month on whether there was a case for research with hybrid embryos. Earlier in April, however, the Science and Technology Committee criticised the HFEA for deferring judgment on the applications, in a report that called for immediate action to permit research using some forms of human-animal chimera under licence.

“Having regard to the scientific evidence produced during the Committee’s inquiry, and that the recommendations are the consensus view of a Parliamentary Committee”, the bill introduction says, the government is prepared to accept that legislation should provide for the creation of certain interspecies hybrids and chimeras listed in Clause 17 (2) of the draft bill for research purposes, subject to the usual requirements for embryo research in the 1990 Human Fertilisation and Embryology Act (i.e., that the research is necessary and desirable).

Draft bill lists exceptions

The draft bill, which in its final form will supersede the 1990 Act, lists these exceptions as:

- Cytoplasmic hybrids: embryos created by replacing the nucleus of an animal egg or a cell derived from an animal embryo with a human cell or the nucleus of a human cell.

- Human transgenic embryos: human embryos that have been altered by the introduction of any sequence of nuclear or mitochondrial DNA of an animal.

- Human-animal chimera: human embryos that have been altered by the introduction of one or more animal cells.

The list includes “the cytoplasmic hybrids that the [Parliamentary] Committee particularly wants to see allowed, and for which the HFEA has received two licence applications, but does not include ‘true’ hybrids created from mixing human and animal gametes”, the preamble comments.

It is also “important that we have the views of the pre-legislative scrutiny committee on this revised proposal”, the draft bill says. “We will therefore ask the committee specifically to consider it, including, if they agree with it, whether it should be effected by a change to the draft clause in the Bill or through regulations.”

Lukewarm response from observers

The draft bill drew a tepid response from the biotechnology industry, with Aisling Burnand, chief executive of the BioIndustry Association, commenting: “Despite Government’s acceptance in principle that legislation should allow the creation of hybrid embryos for research purposes, it is disappointing that this has not been included as a specific provision in the Bill itself … We call on the pre-legislative scrutiny committee to ensure that this research is permitted without delay by changing the draft clause in the Bill.”

Liberal Democrat MP Dr Evan Harris, who sits on the Science and Technology Committee and has pressed for concessions on hybrid embryos to address the current shortage of human eggs available for research, was less diplomatic. He accused the government of ‘spinning’ concessions when none had actually been made.

All eyes will now be on the Joint Committee on the Draft Human Tissue and Embryos Bill, which is due to report by 25 July 2007. In an encouraging sign for the hybrid embryo lobby, Liberal Democrat MP Phil Willis, chairman of the Science and Technology Committee, has also been appointed chairman of the pre-legislative scrutiny body.