Good news for people suffering from infertility. An international team of researchers reports discovering how a human sperm attaches itself to an egg to create new life.
Although scientists know a sperm can identify an egg when proteins on its head match a variety of sugars in the egg's outer coating, they were puzzled by how the egg captures it. But scientists expect the new discovery to lead to better fertility drugs.
The human egg is coated with a chain of sugars called sialyl-lewis-x sequence or SLeX, which makes the sperm stick to it long enough to drop its load of DNA.
Researchers were able to study the binding process by using ultra-sensitive mass-spectrometric imaging technology. They conducted experiments with a range of synthesized sugars in the laboratory, and finally concluded that SLeX, abundant on the surface of the human egg, specifically binds sperm to an egg.
The study, conducted by scientists from the Department of Life Sciences at Imperial College London, the University of Missouri, the University of Hong Kong and Academia Sinica in Taiwan, was published in the journal Science.
Professor Anne Dell, who led the team of scientists, said the research provides the first insights into the molecular events occurring at the very beginning of human life.
The details we've discovered here fill in a huge gap in our knowledge of fertility and we hope they will ultimately help many of those people who currently cannot conceive, said Dell.
The World Health Organization says infertility afflicts up to 15 percent of reproductive-aged couples around the worldy. In Britain, almost one in every seven couples in Britain has problems conceiving a child for various reasons, still unexplained by medical science.
Dr. Poh-Choo Pang of Imperial College London, who also worked on the study, said that while clinical treatments derived from the discovery are still in the future, the study could herald new possibilities for understanding and addressing fertility problems.
We hope that our study will open up new possibilities for understanding and addressing the fertility problems that many couples face, said Pang.