Sarah Knapton reports for The Telegraph, April 26, 2016, that for the first time, scientists have shown by capturing on film that human life begins in a bright flash of light at the exact moment of conception, as an explosion of tiny sparks erupts from the egg when it meets or is fertilized by a sperm.
The bright flash occurs because when sperm enters an egg it leads to a surge of calcium which triggers the release of zinc from the egg. As the zinc shoots out, it binds to small molecules which emit a fluorescence which can be picked up by camera microscopes.
Scientists had seen the phenomenon occur in other animals but it is the first time is has been also shown to happen in humans.
Not only that, but the size of the flash can be used to determine the quality of the fertilized egg. Researchers from Northwestern Universityin Chicago noticed that some of the eggs burn brighter than others, showing that they are more likely to produce a healthy baby.
Professor Teresa Woodruff, one of the study’s two senior authors and an expert in ovarian biology at Northwestern, said: “It was remarkable. We discovered the zinc spark just five years ago in the mouse, and to see the zinc radiate out in a burst from each human egg was breathtaking. This means if you can look at the zinc spark at the time of fertilization, you will know immediately which eggs are the good ones to transfer in in vitro fertilization. It’s a way of sorting egg quality in a way we’ve never been able to assess before.”
Currently around 50% of fertilized eggs do not develop properly and experts believe that faulty genetic code could be responsible. Some clinics take videos of the egg developing to try pick up problems early, while others check for genetic mutations, but that is an invasive procedure which can damage the tiny egg. Often it is just down to a clinician deciding which eggs look the healthiest.
But the new findings could give an extra indication that an egg is flourishing. A video of nine human eggs coming into contact with sperm enzyme showed two flashed much brighter than the rest.
Co-author Dr. Eve Feinberg said, “This is an important discovery because it may give us a non-invasive and easily visible way to assess the health of an egg and eventually an embryo before implantation. There are no tools currently available that tell us if it’s a good quality egg. Often we don’t know whether the egg or embryo is truly viable until we see if a pregnancy ensues. That’s the reason this is so transformative. If we have the ability up front to see what is a good egg and what’s not, it will help us know which embryo to transfer, avoid a lot of heartache and achieve pregnancy much more quickly.”
~Eowyn
