A team of scientists led by Professor Karim Nayernia in Newcastle University successfully grew sperm cells from embryonic stem cells. This article (from The Age) describes the research in further detail. A picture of the mice who were born as a result of the sperm grown in the lab can be seen here. The second article (from Daily Mail) says that the technique could allow men suffering from certain types of infertility to 'grow' their own sperm. One way in which this could be done is by surgical removal of immature sperm cells from a man's testicles and then growing them in the lab and replacing them. The article discusses additonal possible applications of the research.
Interestingly, the first article fails to mention that the resulting mice were far from healthy and suffered from a variety of medical conditions.
As with any new technique, this one too is at least five years from being available to men suffering from infertility, but it may offer hope for the future.
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