A research team at the University of Newcastle has created primitive sperm cells with female embryonic stem cells.

The breakthrough could lead to same-sex couples producing children with both their genes.

Karim Nayernia, Professor of Stem Cell Biology at Newcastle University, told New Scientist:

“I think, in principle, it will be scientifically possible.”

He and his team of researchers will now apply for permission from the university to attempt to turn female bone marrow into sperm, a more practical method than manipulating embryonic stem cells.

However, not all scientists agree that the creation of viable offspring from same-sex sperm and eggs will be possible.

“The presence of two X chromosomes is incompatible with this,” Dr Robin Lovell-Badge, a stem cell expert at the National Institute for Medical Research in London, told the Daily Telegraph.

“Moreover they need genes from the Y chromosome to go through meiosis (DNA replication followed by two rounds of division). So they are at least double-damned.”

The Y chomosome is present in men only.

The Human Fertilisation and Embryology Bill is currently before the House of Lords.

The government may reintroduce a clause that would allow the use of eggs and sperm created from stem cells.

The Bill already allows for two same-sex partners to become the legal parents of a child created through donated eggs, sperm or embryos.

At the moment if a lesbian couple have a baby, one partner has to formally adopt the child in order to be a parent, even if the child is conceived through a fertility clinic.

The new rules would mean that civil partners will automatically become the legal parents of the child, even if the child is conceived ‘informally’ ie: not through a clinic.

The two people named on the birth certificate would also be legally responsible for the child.

On dissolution of a civil partnership the current law allows the courts to consider maintenance payments for the child.

DIY sperm donation will still be legal but under the proposed laws the non-birth mother not in a civil partnership could not be on the birth certificate.