Genetic engineering could, in theory, be used to overcome hereditary diseases, he said. But as the techniques stand now, there's a problem, Dr. Soules noted. Without methods to control where the foreign gene inserts in a human egg's genetic blueprint, more trouble than good could occur. And because the technique would change a person's genetic blueprint, those troubles could be passed on to future generations. If someone were to try the technique on a human egg, it's not clear who, if anyone, would regulate it, experts said this week.
Several states have laws prohibiting research on human embryos.
But ANDi was created by manipulating an unfertilized egg, not an embryo. Lenore Gelb, a spokeswoman for the U.S. Food and Drug Administration, said she thought the agency might regulate the technique used to create ANDi. But gene therapy is traditionally done on body cells and is not designed to affect reproductive cells. In the Oregon experiment, reproductive tissue was altered by injecting DNA into the egg and by creating an animal that presumably has genetically altered sperm. However, Ms. Gelb noted that the agency does not regulate reproductive tissue.