Consider the case of Sharon Saarinen. In 2002, the 38-year-old hairdresser traveled to Beirut in desperate pursuit of a baby. Four years earlier, she and her husband had had their first high-tech child, a daughter conceived through cytoplasmic transfer. In this process, fertility specialists remove a single egg from the mother-to-be and inject it with cytoplasm from the egg of another (usually younger) woman. The rejuvenated egg is inseminated with the father's sperm and inserted into the mother's uterus. The daughter that resulted in the Saarinens' case was apparently perfectly normal. Yet like any child conceived through cytoplasmic transfer, she . . .