The ultimate hope for infertile couples? Scientists create ’embryo-like’ structure in a mouse without using sperm OR eggs
- In mice, cells were turned a bundle which resemble an egg after fertilisation
- The development is hoped to shed light on causes of infertility
- It builds on previous research which has been seen as controversial
- Critics fear it could lead to ‘human clones’ or give false hope to infertile couples
Scientists have taken major steps forward to creating an embryo without using sperm or eggs, giving hope to infertile couples.
A groundbreaking experiment took skin cells from a mouse’s ear and implanted them in a female rodent’s womb, making it pregnant.
Although the US-led team produced a near-perfect embryo with the skin cells, it did not develop into a baby.
This advancement will require a lot more research as it is still in its early stages. It is nowhere near being done in people.
But the breakthrough does give future hope to as many as one in seven couples who struggle to start a family, often because of low sperm counts or poor-quality older eggs.
Scientists have taken major steps forward to creating an embryo without using sperm or eggs. A blastocyst-like form was made from adult mice cells. Pictured, an early stage embryo
However, rather than trying to artificially create a baby using just skin cells, the study was actually designed to shed more light on what can go wrong in pregnancy.
Embryos unable to properly implant in the womb is a leading cause of failed pregnancies.
The team at The Salk Institute and the University of Texas Southwestern Medical Center say it advances research into how life develops from a ball of cells.
The way the 100 or so cells group together has profound implications for diseases later in life, such as Alzheimer’s.
Juan Carlos Izpisua Belmonte, a professor at Salk’s Gene Expression Laboratory, said: ‘These studies will help us to better understand the very beginnings of life; how early on in life a single cell can give rise to millions of cells and how they are assembled in space and time to give rise to a fully developed organism.
What is infertility?
Infertility is when a couple cannot get pregnant despite having regular unprotected sex.
It affects one in seven couples in the UK – around 3.5 million people.
About 84 per cent of couples will conceive within a year if they have unprotected sex every two or three days.
Some will conceive quicker, and others later – people should visit their GP if they are concerned about their fertility.
Some treatments for infertility include medical treatment, surgery, or assisted conception, including IVF.
Infertility can affect men and women, and risk factors include age, obesity, smoking, alcohol, some sexually transmitted infections, and stress.
Fertility in both genders decreases with age – most rapidly in their 30s.
‘Importantly, this work avoids the use of natural embryos and is scalable.’
In 2016 Japanese scientists managed to create baby mice without the need for a female.
They used skin cells from the tip of a mouse’s tail and created artificial eggs with them. But they still needed to be fertilized with sperm.
And just last year mouse ‘embryos’ were created without eggs or sperm for the first time at the Hubrecht Institute in the Netherlands.
But the new study is the first to successfully implant the cells into a womb and cause a pregnancy.
For the first time, the structures, which are called ‘blastoids’, contain all three types of cell needed to form a mouse foetus and placenta.
They were created by taking skin cells from a single mouse’s ear, then reprogramming them into stem cells which can become any type of cell in the body.
To make them become like an embryo, the cells were grown using a specific cocktail of chemicals and growth factors.
Professor Alfonso Martinez Arias, a genetic professor at the University of Cambridge, said: ‘The work is an extension, or further elaboration, from published work, but an important one.
‘In this work, they obtained mouse blastoids with the three cell types, and they implanted in mouse wombs.
‘However… they do not show that the implanted structures go to term in mice or even that they develop into anything as recognisable as a mouse embryo.
‘In order to live up to the opening statement of helping inform issues around health problems, they would need to show that these contraptions develop beyond the stages that they show here.
‘If we don’t we shall be using hype to play with hopes.’
Dr Harry Leitch, a stem cell biologist at Imperial College London, added: ‘I would caution against interpreting the current study as showing that embryos can be made from adult tissues.
‘This has the potential to raise undue ethical concerns, the structures made are not embryos, and the research is in mice not humans.’
Professor Rivron has previously said: ‘I do not believe in using blastocysts for human reproduction.’
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