They see a microscopic flash at fertilization, a burst of fluorescence that marks a sudden release of zinc from the human egg ...

Katsuhiko Hayashi pulls a clear plastic dish from an incubator and slides it under a microscope. "You really want to see the actual cells, right?" Hayashi asks as he motions toward the microscope.

They're leading in the development of IVG, new fertility technology that could make sperm and eggs from practically any cell in the body. The... Japanese scientists race to create human eggs and sperm ...