The debate over British legislation on embryology intensified last night following proposals to allow babies to be conceived using “artificial” sperm and eggs.

The government already faces a rebellion by Roman Catholic Cabinet ministers and Labor members of Parliament, dozens of whom may vote against the Human Fertilization and Embryology Bill.

The legislation would allow the creation of hybrid animal-human embryos for scientific research. Yesterday it emerged that ministers are considering supporting an amendment which would allow so-called artificial gametes — sperm and eggs — to be used to create a human pregnancy through IVF. The technique involves taking embryonic cells from a would-be parent and growing them into sperm in a laboratory.

That would allow groups such as cancer sufferers who have been made infertile by treatment, and women who cannot produce their own eggs, to have children who are genetically related to them.

The Liberal Democrat science spokesman who will table the amendment, Evan Harris, said: “There is no good explanation for not allowing this option for people who have survived cancer and cannot have children.”

The public health minister, Dawn Primarolo, said the technique could help alleviate the shortage of sperm donors, but she accepted there were “profound ethical questions.” The science is in its early stages and has so far only been used to create pregnancies in mice. It would probably be a decade before a human pregnancy could be achieved. The campaign group Comment on Reproductive Ethics said the technique could lead to the “ultimate incest” of a single person being both mother and father of the same child.

The latest development will further anger Roman Catholic Labour Parliament members who have already rejected a Government offer to allow them to abstain from a vote on the bill, which is a key part of the legislative program announced in the Queen’s Speech.

It has been championed by Gordon Brown who believes it is vital in the fight to cure conditions such as motor neurone disease and cystic fibrosis.

The bill will allow for the creation of animal-human embryos — by injecting animal cells or DNA into human embryos or human cells into animal eggs — to be used in medical research and then discarded. It will also reform the fertility laws, meaning that clinics will not have to consider the “need for a father” before providing IVF treatment. This means lesbian couples could be registered as legal parents.

Labour members of Parliament will be under a three-line whip to back the legislation. The Conservatives have given their members of Parliament a free vote on what they deem an issue of conscience.

What the Bill Would Allow

CHIMERA EMBRYOS

The bill would allow scientists to create hybrid or “chimera” embryos by inserting human DNA into an animal cell. The resulting embryo would be used for research but pro-life campaigners and Catholic leaders argue the created embryos are human and the process would involve needless destruction of human life. Scientists say the hybrid embryos will allow them to better understand diseases including Parkinson’s, Alzheimer’s, and motor neurone disease. Implanting the hybrid embryos into either a woman or an animal will be forbidden but opponents fear maverick scientists could illegally try to create a “chimera” baby.

NO FATHER NEEDED

Clinics offering IVF treatment would no longer be required to consider the need for a father to be involved in the upbringing of the child. The bill would recognize same-sex couples as legal parents paving the way for two-mother families and allowing lesbian couples to have children. The leader of the Roman Catholic Church in England and Wales, Cardinal Cormac Murphy-O’Connor, has condemned the move as “profoundly wrong.”

EMBRYO SCREENING

The bill would allow screening of embryos for genetic abnormalities which could lead to disabilities or serious conditions. Embryos will also be screened to see if they are a tissue match for any sibling with a life-threatening illness. Parents would be banned from deliberately selecting an embryo which would develop a certain abnormality. That clause has angered some deaf parents who want a deaf child. Choosing an embryo based on gender would also be banned.

INFORMATION FOR CHILDREN

Children conceived from donated sperm or eggs will be allowed, at the age of 16, to ask for information on any half-siblings who are offspring of the same donor. They will also be able to check whether they are related to someone they want to marry and request information about their donor parent.