On what will Labour MPs now have a free vote?

The free votes will apply to three clauses, governing human admixed embryos, “saviour siblings”, and the “need for a father” during fertility treatment.

Didn’t the Prime Minister mention IVF research too?

Yes, but Downing Street and the Department of Health admitted later that he had been mistaken. He meant to say the need for a father

What are human admixed embryos?

These embryos contain both human and animal material. They are useful for creating cell models of conditions such as motor neuron disease, which can be used to develop new drugs. The main type is 99.9 per cent human in genetic terms, and the Bill will allow scientists to culture these for 14 days. It is already illegal to implant them into animals or humans.

What are saviour siblings?

These are children born from embryos that have been genetically screened to ensure they share the same tissue type as a sick sibling. This means that cells from their umbilical cords can be used in life-saving transplants. While their creation is already legal, this relies on judges’ interpretation of an old law that does not mention the procedure. The technique will now get statutory approval.

What does “need for a father” mean?

Under current law, fertility clinics must consider a child’s need for a father before approving patients. Though this does not automatically deny treatment to single women and lesbians, the Government considers it discriminatory. It plans a new requirement to consider “the need for supportive parenting”.

What about the whole Bill? Will that get a free vote?

No. Labour will not whip votes on amendments to these three clauses, but if they remain in the Bill the Government will expect its MPs to support it at final reading.

Will the concessions satisfy critics?

Partially. Some MPs may still rebel on the final vote, and others object to measures that will still be whipped.

What else remains controversial?

The likeliest flashpoint is a measure that will grant automatic parental rights to gay couples who conceive by sperm donation or surrogacy. There may also be rebellions over embryo screening for disease, and consent laws for cloning research. Some liberal-minded MPs may object to an indefinite ban on artificial sperm and eggs.

What effect will the free votes have?

All three clauses are still expected to pass. While about 50 Labour MPs may vote against, about 40 Conservatives and 50 Lib Dems are likely to back them. The majority could top 100.

What do scientists and patient groups think?

Most approve of the free votes. They are confident of getting the measures through anyway, and fear that a whipped vote would undermine the authority of the resulting law.

Why didn’t Gordon Brown give Labour MPs a free vote in the first place?

There was a fear within government that opponents of research using human embryos would table wrecking amendments to the Bill unless its progress was tightly controlled. When the legislation passed though the Lords, Labour peers were on three-line whips to vote as ministers directed.

Are issues such as embryology traditionally treated as matters of conscience rather than party policy?

Yes. The Government appears to have got itself into a tangle, mixing Mr Brown’s wish to keep Britain as a world leader for the bioscience industry with specific provisions in the Bill that many regard as questions of morality.

The Conservatives have offered their MPs free votes. Liberal Democrats have free votes on most issues, although a handful are party policy and will be whipped.

The Cabinet ministers Ruth Kelly, Des Browne and Paul Murphy are unhappy with parts of the Bill. Are they the only ministers with concerns?

No. Even members of the Whips’ Office such as Tommy McAvoy and Frank Roy, who are supposed to enforce the voting instructions issued to Labour MPs, are unhappy at the prospect of a three-line whip telling back-benchers to support the Government. Would the Government lose the Bill if there were a free vote? The Bill is likely to pass anyway. There are 64 voting Catholic MPs, according to The Catholic Register, about 10 per cent of the House of Commons. Although Catholics are by no means the sole opponents of the Bill, their leaders have been the most vocal. There should be enough Conservative and Lib Dem MPs prepared to support the Bill to get it through the Commons, even if amendments are carried to some of its details.

Why is there such a fuss now? The Bill may not come to the Commons for two months.

The Catholic Church got its fingers burnt by intervening too late in the row last year over regulations forcing its adoption agencies to embrace adoption by gay couples. This time it has prepared the ground much earlier, inviting Catholic MPs to meetings and lobbying MPs well before any votes in the Commons in an attempt to mobilise public and political opinion.

What does the Bill do?

Britain’s laws governing fertility treatment and embryo research are 18 years old, and there is wide agreement that they are out of date. The Bill reforms IVF rules that many doctors consider anachronistic, and regulates new areas of research.

What are its provisions for fertility treatment?

It lifts the requirement that doctors consider a child’s need for a father before starting fertility treatment, it bans sex-selection for social reasons, and introduces new curbs on the sale of sperm over the internet. It also writes into law the circumstances in which embryos can be screened for genetic disease, or for their suitability as tissue donors for sick siblings.

What about medical research?

Experiments involving embryonic stem cells and therapeutic cloning are already legal, but the Bill also permits scientists to conduct research on “human admixed embryos” that contain both human and animal material.

What is a human admixed embryo?

It is an umbrella term for an embryo that contains both human and animal material, which includes chimeras, hybrids and cytoplasmic hybrids or “cybrids”. Chimeras are formed by merging human and animal embryos; hybrids by fertilising a human egg with an animal sperm, or vice versa; and cybrids by inserting human DNA into an animal egg from which the nucleus has been removed.

Why do scientists want to make these?

To study disease, for which cybrids are particularly useful. In genetic terms, these embryos are 99.9 per cent human, and they can be made from the DNA of patients with conditions such as motor neuron disease. These cells can then be used to investigate how these conditions progress, and to develop new treatments.

What are the safeguards?

It is already illegal to culture any human embryos, including the admixed variety, for more than 14 days. It is also illegal to place admixed embryos in either a human or animal womb. Both laws will be retained, and scientists must show that their research is “necessary or desirable” to be awarded a licence.

What are the ethical objections?

Critics, particularly from the Roman Catholic church, argue that admixed embryos are an affront to human dignity and the sanctity of embryonic life. Most of those who object to their use, however, also oppose all research on human embryos. Patient groups and scientists argue that it is immoral not to allow this research, because of its medical potential.

Didn’t the Government once object to hybrids, too?

Yes. When the Bill was first published in draft form, admixed embyros were to be banned, but this provoked furious protests from scientists and patient groups. A scrutiny committee of MPs and peers backed the scientists, and ministers agreed to change the Bill.

So are doctors and scientists happy now?

For the most part, yes. They still have concerns over some of the Bill’s provisions surrounding consent and treatment licences, but most think that it is broadly a sound piece of legislation that will encourage responsible medical research.

What do the public think?

Though Cardinal Keith O’Brien, the leader of the Catholic Church in Scotland, has claimed that admixed embryos have no public support, polling evidence suggests otherwise. A consultation by the Human Fertilisation and Embryology Authority found that 61 per cent of the public back this work for improving research.

What happens now?

The Bill has cleared the House of Lords, and is expected to be debated in the Commons in May.

Will there be a free vote in the House of Commons?

The Conservatives and Liberal Democrats will give their MPs a free vote on most aspects of the Bill, but Labour has refused to do this so far. Catholic leaders, and many advocates of more liberal laws, want a free vote, and three Catholic Cabinet ministers are said to be considering resignation if they are not allowed to oppose the Bill. Yesterday No 10 was playing down reports that Gordon Brown was preparing to allow Labour MPs and even ministers the option of voting against the Human Fertilisation and Embryology Bill. There may be a compromise by which ministers would be permitted to abstain.

Would the Bill pass if Labour allowed a free vote?

Probably. At least 40 Conservative MPs and 45 Liberal Democrats support the Bill as it stands, and these are thought to outnumber Labour members who would oppose it.

Any other controversies?

Plenty. The Government has agreed to allow discussion of amendments that would alter abortion legislation, and all parties will allow a free vote on these. Some deaf activists also object to a provision that would ban the deliberate selection of embryos that carry disabilities.

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