Human skin DNA fertilized to make embryo for the first time

American scientists, for the first time, made human embryos at an early stage by manipulating DNA drawn from skin cells, then by fertilizing it with sperm.

The technique could overcome infertility due to old age or disease, using almost all cells in the body as a starting point for life.

This could even allow same -sex couples to have a genetically linked child.

The method requires significant refinement – which could take a decade – before a fertility clinic can even consider using it.

The experts said that it was an impressive breakthrough, but that it took an open discussion with the public on what science made possible.

Reproduction was once a simple story of the sperm of man meets the egg of the woman. They merge to make an embryo and nine months later, a baby was born.

Now scientists change the rules. This last experience begins with human skin.

The technique of the research team of Oregon Health and Science University takes the nucleus – which houses a copy of the entire genetic code necessary to build the body – from a skin cell.

This is then placed inside a donor egg which was stripped of its genetic instructions.

Until now, the technique is like that used to create Dolly sheep – the first cloned mammal in the world – born in 1996.

However, this egg is not ready to be fertilized by sperm because it already contains a full suite of chromosomes.

You inherit 23 of these DNA bundles from each of your parents for a total of 46, which the egg already has.

Therefore, the next step is to persuade the egg to reject half of its chromosomes in a process that researchers have called “mitomeiosis” (the word is a fusion of mitosis and meiosis, the two ways of dividing cells).

The study, published in the journal Nature Communications, has shown that 82 functional eggs were done. These were fertilized with sperm and some increased in the first stages of embryos development. None have been developed beyond the six-day stadium.

“We achieved something that was considered impossible,” said Professor Shoukhrat Mitalipov, director of the Center for Embryonic Cell and Gene Therapy at the Oregon University of Health.

The technique is far from being polished because the egg randomly chooses the chromosomes to throw away. He must end up with one of the 23 types to prevent the disease, but ends up with two of some and none of the others.

There is also a bad success rate (around 9%) and chromosomes are missing an important process where they reorganize their DNA, called crossing.

Professor Mitalipov, a world -renowned pioneer in the field, said to me: “We have to improve it.

“Finally, I think that is where the future will go because there are more and more patients who cannot have children.”

This technology is part of a growing field aimed at making sperm and eggs outside the body, known as Gametogenesis in Vitro.

The approach is always in terms of scientific discovery rather than clinical use, but vision is to help couples who cannot benefit from IVF (in vitro fertilization) because they do not have sperm or eggs to use.

This could help elderly women who no longer have viable eggs, men who do not produce enough sperm or people whose treatment of cancer has left them infertile.

The field also rewrites the rules of parenting. The technique described today does not have to use a woman’s skin cells – it could also use that of a man.

This opens the door to same -sex couples with children genetically linked to both partners. For example, in a couple of the same male sex, the skin of a man could be used to make the egg and the sperm of a male partner used to fertilize it.

“In addition to offering hope for millions of people with infertility due to the lack of eggs or sperm, this method would allow the possibility of same -sex couples to have a child genetically linked to the two partners,” said Professor Paula Amato, of Oregon Health and Science University.

Roger Sturmey, professor of reproductive medicine at the University of Hull, said that science was “important” and “impressive”.

He added: “At the same time, such research strengthens the importance of a continuous open dialogue with the public on new progress in procreation research.

“Percées like this impress the need for robust governance, to ensure responsibility and strengthen public confidence.”

Professor Richard Anderson, deputy director of the MRC Center for Reproductive Health at the University of Edinburgh, said that the ability to generate new eggs “would be a major advance”.

He said: “There will be very important security problems, but this study is a step to help many women have their own genetic children.”