NEW EXPERIMENTAL FERTILITY TECHNIQUE



By PETER O'CONNOR
Associated Press Writer
Friday, July 13, 2001

	   CANBERRA, Australia (AP) - Australian researchers say they have
pioneered in mice a potentially revolutionary technique that
fertilizes female eggs without the need for male sperm.
	   Developed by Dr. Orly Lacham-Kaplan at the Institute of
Reproduction and Development at Monash University in Melbourne, the
procedure uses half the genetic material from any cell in the body,
either male or female, to fertilize an egg.
	   Lacham-Kaplan stressed that the experiments are in extremely
early stages. But Dr. Robert Winston, a London fertility expert,
said that if the technique works in humans, ``this is actually
genuinely revolutionary and potentially very important.''
	   The real advantage of the technique is for men who cannot
produce sperm, Winston, who was not connected with the research,
told the British Broadcasting Corp.
	   The technique is the latest variation of new reproductive
technologies to emerge since Dolly the sheep was produced by
cloning in 1996.
	   Dolly was created by replacing all the chromosomes of an egg
with a cell from an adult sheep, so that Dolly was a genetic copy
of the sheep that donated the cell.
	   All cells in the body, except the egg and sperm, contain two
sets of chromosomes, one inherited from the father and one from the
mother. The egg and sperm contain one set each. Adding genetic
material to either of them would result in too many sets of
chromosomes.
	   Last week, U.S. scientists reported that they may have found a
way around that problem.
	   They removed the chromosomes from a human egg and replaced them
with those from a cell of an infertile woman. An electric shock
then prompted the new egg to eject the spare set of chromosomes
before it was fertilized with sperm.
	   Similarly, in the Australian method, the donated adult cell was
chemically stimulated to jettison one of its sets of chromosomes
before it was joined with an egg. The result was an egg with two
sets of chromosomes, just as happens with natural fertilization.
	   While the U.S. technique could one day allow women with
poor-quality eggs to have a baby that is genetically theirs and
their partner's, instead of them having to use a donated egg, the
Australian technique could one day allow men to father a child
instead of having to use donated sperm.
	   Theoretically, these new techniques could eventually also allow
same-sex couples to reproduce.
	   Lacham-Kaplan used the technique to fertilize mouse eggs in a
laboratory using cells from an adult female mouse and developed
embryos up to five days old.
	   The normal gestation period for mice is 21 days.
	   Lacham-Kaplan told The Associated Press her research is still in
its ``very early, early'' stages.
	   ``We did go to fertilization, we did get embryo development, we
did get about 30 percent of the eggs that fertilized to produce
into the final stage of development in culture, that was quite
exciting,'' she said. ``What we do need to do next is to transfer
those to surrogate mothers to see if we can obtain babies.''
	   Lacham-Kaplan said she hopes to produce baby mice within the
next year, but expects ``more failures than success.''
	   Some experts believe the new technologies will take a long time
to refine and that creating embryos using DNA from adults could
introduce serious genetic abnormalities, at least at first.
	   Winston said the strength of the technique was that it would
solve the problem of a man having no sperm, making cloning
unnecessary for them.
	   ``This actually is a much better technique and ethically much
more acceptable because you have chromosomes from two partners,''
he said.
	   Lacham-Kaplan said she is well aware of the ethical concerns.
	   ``I am not trying to play God, I am not trying to replace God or
play with nature,'' she said. ``My belief is that if I can help
people to have children I will do that regardless of what other
people think.''

"Orly Lacham-Kaplan (http://www.med.monash.edu.au/eprb/staff/kaplan.html)"

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