The research from England, Australia and Belgium, presented this week at a conference in Copenhagen, has huge implications for fertility, stem cell research and cloning possibilities.
According to research into human embryonic stem cells carried out by British scientists at the University of Sheffield, sperm and eggs could be available within 10 years for fertility treatment.
The research showed it could be possible to produce primordial germ cells – the precursors of sperm and eggs – from embryonic stem cells.
Once these were obtained, the best method would be to transplant them directly into a man’s testis or a woman’s ovary, where the environmental and hormonal conditions were right to turn them into sperm or eggs, the report said.
Therapeutic cloning would be necessary to ensure that the germ cells carried the patient’s genes.
Anna Smajdor, a medical ethicist at Imperial College London, said the discovery “opens new and challenging possibilities.”
“Single men could even produce a child using their own sperm (with an artificial egg), opening the way to a new form of cloning. Women’s fertility would no longer need to be curtailed at the menopause.”
“This is probably 10 years away… we have a lot of work to do, and we have to prove it’s safe,” Professor Moore said.
Australian researchers have used the embryonic stem cells of mice to develop ovary-like structures containing eggs.
Eggs obtained from the process were at an early stage of development and more studies were required to explore whether they were able to mature, be fertilised and develop normally as embryos.
Dr Lacham-Kaplan at Monash University said her ultimate goal was to find ways to help infertile couples have children.
She hopes one day the process can be applied to develop eggs for sterile women containing their own genetic material.
“The ability to develop eggs… could primarily assist sterile women but could also reduce the ongoing strain on donor egg programs,” she said.
“It could … help create a bank of eggs that could be used for nuclear transfer – where an egg’s genetic material is removed and replaced with that of a sterile woman.”
In Belgium, scientists say they have cloned the first human embryos from unripe eggs matured in the laboratory.
They’ve demonstrated immature eggs that aren’t suitable for fertility treatments can be grown in the laboratory and then used to create embryos for stem cell research and therapeutic cloning to treat a range of diseases.
“We’ve created an alternative source for human eggs for cloning,” Joisiane Van der Elst, one of the researchers, told the Copenhangen fertility meeting.
Stem cells are master cells that have the capability to grow into any type of cell in the body. Scientists believe they could act as a type of repair system for the body.
Embryonic stem cells are currently derived from very early embryos left over from infertility treatments.
Scientists are also trying to create very early human embryos to mine them for stem cells for therapeutic cloning.
The use of embryonic stem cells is highly controversial because it involves the destruction of embryos.
The Belgian scientists said the cloned embryos formed from the immature eggs grew to the 8-16 cell stage, which was too early to extract stem cells.
They are continuing their research to try to get the cloned embryos to the blastocyst stage when they can obtain the stem cells.
Although they still have a long way to go, the researchers said their ultimate goal is to develop treatments for patients who suffer from infertility.
“Our final goal is to use human therapeutic cloning for infertility treatment by creating artificial eggs and sperm for patients who are infertile because of absence or premature loss of eggs or sperm,” co-researcher Bjorn Heindryckx said.