A new technology called CRISPR could allow scientists to alter the human genetic code for generations. That's causing some leading biologists and bioethicists to sound an alarm. They're calling for a worldwide moratorium on any attempts to alter the code, at least until there's been time for far more research and discussion.
It's not new that scientists can manipulate human DNA — genetic engineering, or gene editing, has been around for decades. But it's been hard, slow and very expensive. And only highly skilled geneticists could do it.