Human sperm 'created' in laboratory
Updated on 08 July 2009
Scientists from Newcastle University have created human sperm in the laboratory in the latest advance in stem cell science.
They say their intention is to use the sperm for research to understand why some men are infertile, but they hope that eventually the technique could lead to a treatment for male infertility. Under current legislation that is illegal.
Stem cells from a human embryo have the unique ability to transform into any of the specialised cells the body needs. The team at the North East England Stem Cell Institute, led by Professor Karim Nayernia, treated embryonic stem cells to produce a small number of living sperm.
In particular, they were able to trigger meiosis, where the cells divide and split the set of chromosomes inside the nucleus. The sperm had tails and swam, and had the right number of chromosomes.
Ordinary cells contain 46 chromosomes but sperm have half that number as the rest would be supplied from the female.
Their announcement has drawn criticism from other stem cell scientists who say they have not shown that the sperm are fully normal in both physical structure and biological behaviour.
Professor Robin Lovell Badge, from the Medical Research Council Institute of Medical Research, said: "Although they find that some of the sperm cells have tails and can swim, this is not evidence of normality."
In response, Professor Nayernia told Channel 4 News he had never claimed that what his team had done was any more than "proof of principle".
The creation of human sperm follows similar work in mice by the same team. Then they used the lab-made mouse sperm to breed young mice, but many of the offspring were deformed and none lived for very long, suggesting there was something wrong with the sperm.
The risk of the same happening in humans is why fertility treatment using stem cell-derived sperm is illegal, but Professor Nayernia believes he can make the technique safe within a decade and a debate on changing the law should begin "sooner, rather than later".
