DNA breakthrough gives new hope for millions of infertile men


DNA breakthrough gives new hope for millions of infertile men

Scientists reveal that many men may only be infertile because their sperm is damaged upon ejaculation

Sarah Knapton

The sperm of infertile men may be as healthy as fertile men, British scientists have discovered in a breakthrough that offers hope to families struggling to conceive.
Researchers found that some men may only be infertile because their sperm becomes damaged after it travels through a series of ducts. It suggests that something odd and toxic is happening along its path to the outside, but the sperm are healthy so long as they are extracted directly from testicles.
The discovery offers hope for men who struggle to become fathers even through in vitro fertilisation (IVF), as well as hinting at a new cause of male infertility.
Jonathan Ramsay, consultant urologist of Imperial College London, who led the study, said: “When we looked at ejaculated sperm, we found that the extent of sperm DNA damage was much higher in infertile men than in fertile men, with roughly 15% in fertile men, but 40% in infertile men. It wasn’t a surprise to see greater DNA damage in ejaculates of infertile men. What we didn’t expect was the consistency in these results when we looked at sperm taken directly from the testicles of infertile men. We found that it was of similar quality to that of ejaculated, fertile sperm.”
In research to be presented at the European Association of Urology Congress in Barcelona, British scientists took testicular and ejaculated sperm samples from 63 infertile men. They examined the sperm for DNA strand breaks in both the testicular and ejaculated sperm and matched it to semen taken from a group of 76 fertile volunteers. The sperm was measured using The Comet Test, a technique developed by Queen’s University Belfast, now run by spin-off company ExamenLab.
Although there was a major difference in the ejaculated sperm in the infertility group, the sperm from the testes was found to be similar to that of the control group.
Sheena Lewis, emeritus professor at Queen’s University Belfast and founder of Examen Lab, said: “This opens the way to taking sperm directly from the testes of men who have highly fragmented ejaculated DNA and failed cycles of treatment and trying to achieve fertility with these testicular sperm.
“We can’t yet prove that this sperm DNA damage is the main cause of male infertility ... or that using testicular sperm directly would help improve their chance of getting pregnant, but the work certainly points in that direction.”
One in seven British couples struggle with infertility. In roughly 50% of cases the problem lies with the male partner, yet in 75% of infertile men, the cause is unexplained.
– © Telegraph Media Group

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