Position: Director, University of California, Los Angeles, Program on Medicine, Technology, and Society
Issue: Designer babies. Advances in biology and medical technologies are pushing the frontiers of genetic engineering to the point where the possibility of parents’ selecting specific traits for their children is closer to science fact than fiction.
Personal Point of Impact: Author, Redesigning Humans: Our Inevitable Genetic Future
Technology Review: You claim that parents will be able to genetically enhance their unborn children. But how realistic is the idea of genetically engineering embryos, eggs, or sperm-our “germline cells”-to create designer babies? It sounds like science fiction.
Gregory Stock: For the immediate future, it is. You have to have two things first: something worth doing and a safe, reliable way of doing it. At present, neither exists. There really are no platforms for doing reliable, safe interventions of this sort. And even if you had a safe way of inserting genes, you wouldn’t have anything to do, because we don’t know enough about our genetics to accomplish anything that would be worth whatever risks are involved.
But that doesn’t mean that such modifications are particularly distant. Both those requirements, I expect, will be met within the next generation, so it’s good to start thinking about these sorts of things now. The potentials will arrive quickly once the technology moves forward.
TR: In what ways are people already starting to confront the ethical issues associated with choosing children’s genetic fates?
Stock: We are beginning to open up our biology and intervene in realms that have always been beyond our reach. Well before the technology of germline intervention itself is ready for prime time, we’ll be dealing with sophisticated screening that allows prospective parents to use genetic tests to pick and choose among their embryos. Preimplantation genetic screening already has been used with in vitro fertilization for a decade to avoid serious genetic diseases like cystic fibrosis. Parents test their embryos for the mutation and discard those that are afflicted. Soon, such testing will move to a broad array of potential genetic diseases, then to lesser vulnerabilities like a heightened risk for severe depression, and then to nondisease traits-choices about temperament and personality.
The controversies provoked by these capabilities and how parents use them will be very similar to the ones we will face in manipulating the germline directly. Functionally, there’s little distinction between going in and modifying a gene to correct a mutation that will cause Huntington’s disease and simply screening to avoid that mutation; or between picking an embryo with certain potentials and adding genes to create them. So I see this as a broad policy debate that is less about a particular technology than about the capacity for parents to make choices about the genetics of their children.