Subscribe to the BioNews newsletter for free

Advanced Search

Search for

Like the Progress Educational Trust on Facebook

The Fertility Show, Manchester Central, 24-25 March 2018


Sperm from stem cells could help some types of male infertility

21 August 2017

By Shaoni Bhattacharya

Appeared in BioNews 914

Cells from genetically infertile male mice have been turned into sperm, and used to produce healthy pups.

Researchers hope the technique could one day help men with certain causes of infertility. Experts hailed the work as 'very encouraging' and 'fascinating science', while noting that the technique is experimental only, and raises ethical and legal considerations should it be developed for humans.

'Our approach allowed us to create offspring from sterile XXY and XYY mice,' says first author Dr Takayuki Hirota at the Francis Crick Institute in London. 'It would be interesting to see whether the same approach could one day be used as a fertility treatment for men with three sex chromosomes.'

Having an extra sex chromosome – three instead of two – can cause infertility in mice and men. In humans, about one in 500 men may have either an extra X chromosome (Klinefelter's syndrome) or an extra Y chromosome (Double Y) in their genomes.

British and Japanese researchers aimed to remove the extra sex chromosome in infertile male mice with this problem. They took cells from the ears of the mice and cultured them in the lab to collect fibroblast (connective tissue) cells. They then coaxed the fibroblast cells into iPS, induced pluripotent stem cells – in the process some of the cells lost their extra sex chromosome.

Using specific chemical signals, the researchers could guide these stem cells into becoming the cells which can develop into sperm. When these were transplanted into the testes of live mice, they matured into sperm, which were used in assisted reproduction to give healthy pups.

Others agree the study offers potential. 'Although a mouse study, this research is exciting, since it raises the future possibility that sperm without the extra X chromosome could be made,' said Dr Channa Jayasena, a reproductive endocrinologist at Imperial College London. 'This could offer potential hope for affected couples.'

Indeed, a preliminary experiment by the researchers turning fibroblast cells from men with Klinefelter's syndrome into stem cells in vitro managed to lose the extra X chromosome.

But, Dr Jayasena notes the new study 'raises important ethical issues'.

Professor Allan Pacey at the University of Sheffield, UK, said: 'This is very encouraging. The only fly in the ointment is that currently the use of such sperm in the UK is not lawful and it would take a change of primary legislation to allow us to use such sperm in infertility treatment.'

While praising the study, Professor Adam Balen, chair of the British Fertility Society, said its application in improving fertility in men with Klinefelter’s syndrome 'is a long way off clinical practice'.

He also noted: 'Furthermore there are possible significant risks outlined in the paper which mean that any therapeutic application is far from certain.'

The study, published in Science, found that when the cells were transplanted into the testes of mice, some of the animals developed teratomas.


06 November 2017 - by Lea Goetz 
Men with infertility experience stigmatisation and a lack of support, a first survey on the subject found...

14 November 2016 - by Dr Katie Howe 
US researchers have created functional eggs using DNA from small cells that normally form as waste products during egg development...
24 October 2016 - by Dr Katie Howe 
Scientists in Japan are the first to have created live mouse pups from eggs that were made from stem cells...
03 May 2016 - by Ayala Ochert 
Spanish scientists say they have created rudimentary sperm-like cells from skin and bone marrow cells taken from adult males...
21 March 2016 - by Dr Julia Hill 
Scientists have created human stem cells with 23 chromosomes instead of 46, the normal number in a complete genome contained in almost all cells...
06 May 2014 - by Siobhan Chan 
Skin tissue from infertile men has been converted into sperm cell precursors after their stem cells were transplanted into mice...

Be the first to have your say.

You need to or  to add comments.

By posting a comment you agree to abide by the BioNews terms and conditions

- click here to enquire about using this story.

Published by the Progress Educational Trust
Advertise your products and services HERE - click for further details

Good Fundraising Code

Become a Friend of PET HERE and give the Progress Educational Trust a regular donation