It’s the first thing we’re told about reproduction in school: life begins when sperm meets egg.
But new research published in science journal Nature has resulted in that rule potentially being thrown out of the window, as scientists have successfully created an embryo without using either.
They’ve suggested that the technique, which so far has only been carried out in mice, could mean that a mouse could be created without using sperm or eggs in three years.
Two types of stem cell – which can come from human embryos or adult bone marrow, and are able to turn into any kind of human cell – were combined in a dish, and grew into an early form of an embryo (a “blastocyst”.)
It didn’t implant in a womb, however, which would have been the starting point of it growing into a foetus.
It’s apparently the first time that something that could become an actual baby mammal (along with the placenta and yolk sac in the womb) has been created this way.
The discovery could mean that scientists are able to create an endless supply of embryos , which would be useful for medical research including studies into infertility or new medical treatments.
It won’t be used to create human clones, however, the study’s lead researcher said.
Professor Nicholas Rivron of Maastricht University told the Daily Mail: “As you know, embryos are very precious, and it is impossible to use to test drugs on them as you don’t have the numbers.
“With blastocysts you can open up the numbers. This will allow screening medicines in the future.”
He added: “I do not believe in using blastocysts for human reproduction. This is ethically very questionable, this would be clones of somebody who is already alive.
“Human cloning is totally forbidden.”
So don’t worry, we won’t have a science-fiction style clone war on our hands just yet.
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