First Road Map of Human Sex-Cell Development: Scientific American
Original story at scientificamerican.com• 2 mentions • 12 months ago
Researchers have uncovered some of the steps that enable human stem cells to develop into egg cells. Image: Clouds Hill Imaging Ltd./Corbis The causes of infertility, which affects around 10% of couples, are often unknown, but may in some cases result from the body's inability to produce viable gametes — also known as sperm and egg cells. The first study of the development of such 'germ cells' from humans could help scientists to learn how to create them in the laboratory instead. Even though the reproductive age for humans is around 15–45 years old, the precursor cells that go on to produce human eggs or sperm are formed much earlier, when the fertilized egg grows into a tiny ball of cells in the mother’s womb. This ball of cells contains ‘pluripotent stem cells’ — blank slates that can be programed into any type of cell in the body — and researchers are hoping to use these stem cells to treat various conditions, including infertility. But little is known about the early developmental stages of human gametes — owing to the sensitivity of working with human tissue — and most work in this area has been conducted using mice. In a Nature Cell Biology paper today, researchers from the University of California, Los Angeles, trace the development of early germ cells in human fetuses of between 6 to 20 weeks and analyzed when genes were turned on or off.