Researchers at Newcastle-upon-Tyne University in the United Kingdom have developed a breakthrough technique to turn female bone marrow into sperm.
The scientists will take stem cells from a woman donor's bone marrow and transform them into sperm through the use of special chemicals and vitamins. The procedure may also be done with cells from male bone marrow, which can be turned into eggs, paving the way for gay couples to have children without any biological participation by a female.
Professor Karim Nayernia has applied for permission to carry out the work and is ready to start the experiments within two months, New Scientist magazine reported.
The biologist, who pioneered the technique with mice, believes early-stage 'female sperm' could be produced within two years but mature cells capable of fertilising eggs might take three more years.
Early-stage sperm have already been produced from male bone marrow.
Also, the ethical debate over drawing stem cells from an embryo can be avoided, since the cells will be taken from an adult donor.
The technique may revolutionise infertility treatments globally.
If the experiments succeed, the stage would be set for a gay man to donate skin cells that could be used to make eggs. These could then be fertilised by his partner's sperm and placed into the womb of a surrogate mother.
But, besides fears of raising an ethical debate, the children born from artificial eggs and sperm might suffer severe health problems, like the mice in the experiments.
Also, because the female sperm would lack the Y chromosome, such couples would be able to have girls only.
The research also paves the way for a woman to grow her own sperm and use it to fertilise her natural eggs, creating a child to which she is both mother and father.
Similarly, a man could be both father and mother to a child created with his own sperm and a lab-grown egg.
However, researchers believe such children would be at a higher risk of developing genetic abnormalities.
