Of mice and men and assisted reproduction

By SIMON COLLINS science reporter

Gay men may be able to have their own babies if a new technique that works in mice can be made to work in humans.

The technique, reported in this week's New Scientist, has created eggs and sperm in the laboratory for the first time from "stem cells" taken from unborn mouse embryos.

The breakthrough suggests that it may eventually be possible to create human babies using eggs and sperm grown in the laboratory from infertile couples who could be either man and woman or man and man.

It comes just as New Zealand's National Ethics Committee on Assisted Human Reproduction considers an application from two gay men to have a baby using the sister of one of them as a surrogate mother.

In that case, only one of the men would be the father, and the other man's sister would be the mother. The only unnatural thing about it is that the man proposes to fertilise the woman through artificial insemination instead of normal sex.

In contrast, the new technique may eventually allow two men to have a baby by themselves. A woman would still be needed to grow the baby in her womb, but its genetic material could come from the men.

Gay organisations welcomed the news. Edward Bennett of Auckland's Pride Centre said that if the new technique was used for infertile heterosexual couples, then it should be allowed for gay men.

"It's not as if a lot of gay people started off the fertility industry. We just happen to be possible recipients of the side-effects," he said.

"Lots of heterosexual people who are not good parents are allowed legally to have children.

"Apparently when it comes to one of us, a same-gender couple, all of a sudden there is a moral question whether the rights of the children should be addressed.

"All the studies show that children brought up in same-gender relationships are just as healthy emotionally and physically as other children."

However, fertility experts were cautious. Dr Margaret Merrilees of the Auckland District Health Board's Fertility Plus service said a lot more work would have to be done with animals before the technique could be tried on humans.

"If you look at cloning, that certainly has not been shown to be safe," she said. Dolly, the first cloned sheep, died young.

Dr John Peek of Fertility Associates said the first step in the new technique would be cloning, with all its risks of abnormalities.

A donor egg cell would still be required from a woman. Its nucleus containing her genetic material would be removed and replaced by genetic material from the proposed biological parent - the process known as cloning.

The cloned egg cell would then be allowed to multiply and grow into a tiny human embryo. At this stage, all the cells in the embryo are omnipotent "stem cells" which are capable of developing into any human organ.

For years, scientists have been trying to grow a variety of organs from stem cells from embryos.

The latest breakthrough is to use the technique to grow an egg. Surprisingly, the technique has succeeded in growing an egg even where the original genetic material came from a male mouse.

If this works in humans, it would mean that a gay man could, through his genetic material, effectively become a biological "mother". His egg could then be fertilised by sperm from his partner.

It could then be placed in the womb of a surrogate mother and be born about nine months later.