“A revolutionary technology that can edit genetic mistakes.” News that researchers modified the DNA of a human embryo has created shockwaves, reigniting a familiar refrain. “Designer babies.” “Designer babies.” “Designing babies is not allowed in America now, but it’s coming.” It’s not the first time a scientific advance involving embryos has ignited alarm. “A British medical team said today it hopes to create the world’s first test-tube baby by the end of this year.” In the 1970s, the idea of in vitro fertilization was still a dream, but fears of where it might lead were already taking hold. “This is one step toward further modes of manufacturing our children.” “People were just generally scared. They didn’t know what was going to happen. I think it was tied up with the old novel, ‘Brave New World,’ in which the babies there were gestated in what he called bottles.” “Mark Bernard G., inspected and approved.” “To create a baby in the laboratory in a petri dish was considered not just abnormal, it was considered immoral.” “Several other doctors say they are against the idea. They claim that it opens the way for mass production of babies and as they put it, ‘a nightmare of biological engineering.’” “Concerns ranged from: there’s a slippery slope here, once we start making life outside the womb, once we start making life in dishes, won’t we wind up saying that’s the best way to do it for everybody? That we are going to wind up eliminating natural reproduction.” “People said all sorts of nasty things about it. They thought they were creating designer babies. They would create monsters.” “There was fear that someday the techniques could be used to develop something other than a normal human being.” “One MP warned of the dangers of scientific breeding becoming a reality, of a revival of Adolf Hitler’s concept of a master race.” The two scientists at the forefront of the research, Patrick Steptoe and Robert Edwards, conducted their work in a secluded laboratory far away from the media spotlight. “They were doing things like disguising themselves and making sure that their cars were parked in a different location when they went to visit or do any of the work. It was really cloak and dagger.” After more than a decade of research, their controversial experiment became one of the biggest medical stories of the century. “The world’s first test-tube baby was born here in Britain last night.” “A pink, healthy baby girl who began life in a test tube.” “At birth, it came out crying its head off and in very good state, breathing very well.” “Louise came out, she wasn’t a Frankenbaby, she was healthy, she looked normal. The fact that the first human I.V.F. that went to term, resulted in a healthy baby, dramatically changed perspectives on I.V.F.” “We forget now because I.V.F. is commonplace, but really Louise Brown heralded hope for millions of people throughout the world.” That hope, and the media’s fascination, generated hundreds of headlines around the globe. “When I look back on the cuttings — newspaper cuttings, and films, we couldn’t come back home to Bristol for 11 to 12 days, and when we did, there were 100 journalists–plus outside our little house from all over the world. It was just madness.” “The birth of Louise Brown was a Nobel Prize-winning event, not just because of the technology, but because of the beauty of what it did for Louise Brown’s family and for thousands and thousands, now millions of couples around the world who have been able to have children.” Dr. Mark Hughes is part of the team of scientists that took I.V.F. to the next level. In the early 1990s, they pioneered a technique that allows doctors to screen embryos for potentially lethal diseases. “The idea is to make a diagnosis before a pregnancy ever begins so that couples who are at high genetic risk can avoid that disease before they ever get pregnant.” It’s called pre-implantation genetic diagnosis, or P.G.D., a procedure in which couples go through I.V.F., even if they don’t have fertility problems. Doctors then test the DNA of the embryos and only implant healthy ones. “We can say embryo two, five and seven don’t have this genetic condition and they’ll be safe to transfer.” “Not long after Eden was born, we knew there was something that wasn’t exactly right.” When Randy and Caroline Gold’s second child, Eden, was 18 months old, she was diagnosed with mucolipidosis Type IV, or ML-4, an incurable genetic disease with a heartbreaking prognosis. “Kids with mucolipidosis Type IV will likely never walk, they’ll never talk. They’ll go blind by the time they’re 12 years old. And they will have a very limited lifespan.” “High five on that, girlfriend. Love you.” The Golds dreamed of having a third child, but they knew that dream carried big risks. “Because Caroline and I carry the same mutation for ML-4, we have a 25 percent risk with every pregnancy that we can have a child with that disease.” The Golds turned to Mark Hughes, and, using P.G.D., he was able to identify an embryo without the ML-4 mutation. Today, Eden has a healthy little sister, named Shai. “It was an absolute miracle.” P.G.D. has helped thousands of families like the Golds, but it has also reignited a familiar debate. “Is it leading to the creation of designer babies?” “As the science advances, ethical questions about when and where to draw the line when it comes to picking and choosing only the healthiest embryos. Critics say it can become a slippery slope.” “From the very first cases of embryo testing for genetic disease, the slippery slope of designer babies was in everybody’s mind — ‘Oh, we’ll be testing for anything.’” The use of embryo screening procedures like P.G.D. has expanded. They can now test for hundreds of diseases and chromosomal abnormalities. Yet much of the media attention has focused on the doctors who push those boundaries. “This is the room where the magic begins.” “It’s called gender selection.” For over a decade, Dr. Jeffrey Steinberg has been a flash point in the debate, constantly in the news for marketing the use of P.G.D., not just for medical necessity, but to let couples choose the sex of their child. “Dr. Jeffrey Steinberg, Director of Fertility Institutes, says up to 90 percent of his patients come to him specifically because they want to decide whether they have a boy or girl.” “The technology was out there. It was being applied only to preventing diseases. Well, I’ve decided to open the door and expand it and say, listen, this is something that people are interested in, causes no harm, makes people happy. Let’s expand it.” Sex selection for non-medical reasons is illegal in many countries, but not in the United States, where some aspects of the fertility industry are loosely regulated. Many of the procedures cost upwards of $10,000. Yet Steinberg says he has no shortage of patients and is currently marketing a new cosmetic option for what he calls “21st-century parents-to-be.” “25 years ago, I predicted we would be choosing eye color. We’re able to do that now. It turns out, people want blue eyes. Not only are we able to assist with that, but we can offer them a choice of 30 shades of blue eyes.” These claims are met with great skepticism by many scientists and also raise ethical concerns. “Jeffrey Steinberg claims that he can give you a child with a particular eye color. I don’t know what he really means by that, but I think that, again, is an example of how we have to be very careful to draw lines that are clear and can be enforced.” Marcy Darnovsky runs a watchdog group that focuses on the social impact of reproductive and genetic technologies. “What counts as medical? What counts as enhancement? I mean, how could you draw a line?” Today, that question is more relevant than ever. “A medical breakthrough, or the first steps down a dangerous road?” In 2017, researchers at Oregon Health and Science University announced a groundbreaking development. “For the first time in the United States, scientists have edited the genes of human embryos.” Using a technology called Crispr, they were able to correct a defective gene that causes a potentially fatal heart disease, altering a trait that could be passed on to future generations. There was never any intention of creating a pregnancy, but like I.V.F. before it, the breakthrough was received with both excitement and alarm. “Critics worry Crispr could be used to create designer babies. Last year, former Director of National Intelligence James Clapper called genome editing a potential weapon of mass destruction. And Congress has banned turning gene-edited embryos into babies.” “I think a lot of the times those fears are largely overblown.” Dr. Paula Amato is a co-author of the research on editing human embryos. “When you think about the traits that people would like to enhance, things like intelligence or athleticism, we actually don’t know the genes that are responsible for those things. And it’s likely to be more than one gene. So even if you wanted to do that, at least at this point in time, it would be very difficult if not impossible to do.” But the ability to genetically modify embryos could be a new frontier, one in which it is no longer just about changing the genetic traits of an individual, but of all their descendants as well. “I think this is a slippery slope that we’re on. That doesn’t mean that we have to forgo everything along the way. It does mean that we have to make sure we have brakes and we have to make sure we have stopping points.” “All new technologies need to be carefully and properly assessed. I think you can’t have the Wild West. On the other hand, I think you can get yourself into a fear situation where you become paralyzed and can’t do anything.” “When any medical advance is made, any medical advance is made, there is first of all one success. Somebody had to be first. And then there are others.” “There’s six million of us, babies been born through I.V.F., which is fantastic. And I’m actually quite proud to say that it started with me.”