These labs say they can screen embryos for specific traits. Should you? : NPR

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Justin Schleede picks up a tray of small plastic tubes from a black lab bench.

“These are saliva samples and blood,” explains Schleede, a geneticist who oversees Herasight Inc.’s lab in Morrisville, N.C. “We also obtain cells from the embryos.”

Named after the fertility goddess Hera, Herasight is among a few new companies offering polygenic embryo screening, a novel and controversial genetic testing method.

This screening, akin to high-tech fortune-telling, predicts the likelihood of embryos developing into children susceptible to a range of illnesses, from rare inherited conditions like Tay-Sachs to more common ones influenced by genetics such as cancer and diabetes.

“For those who are risk-averse and prefer not to leave things to chance, they come to us to gather as much genomic data as possible to select embryos for the healthiest, disease-free children,” Schleede states.

Some companies, like Orchid Health in Palo Alto, Calif., focus solely on health risks. Herasight extends its services to include predictions about height, BMI, longevity, and IQ. Meanwhile, Nucleus Genomics in New York offers prospective parents the option to select even more traits, like eye color and handedness.

“We refer to it as genetic optimization,” says Kian Sadeghi, founder and CEO of Nucleus Genomics. “We assist people in having their best babies.” These companies use polygenic risk scores, numerical estimates based on genetic variations, to predict certain diseases and traits. Clients utilize these scores to decide which embryos to use for childbearing.

However, the American College of Medical Genetics and Genomics and the American Association of Reproductive Medicine argue that the science behind polygenic risk scores is not yet advanced enough to yield reliable predictions. They emphasize that genetics is just one of many factors, alongside environment and lifestyle, in determining disease risk. Additionally, the ethical implications of such screenings have raised concerns.

Science fiction inches toward reality

Polygenic risk screening for embryos is part of what some futurists have dubbed the “Gattaca Stack.” Named after the 1997 movie that envisioned a dystopian society of genetic selection, the Gattaca Stack would combine technologies like polygenic embryo screening with embryo editing, artificial wombs, and lab-grown eggs and sperm to create genetically enhanced humans.

“I’m very worried about the kind of dystopian world that this way of using technologies could lead to,” says Katie Hasson, the executive director of the Center for Genetics and Society. “At its heart, it’s a vision of … mass-produced, genetically enhanced people, right? It’s an idea of doing genetic engineering at scale with some vision of producing a superior form of humanity, which I think is very troubling.”

But Schleede and his colleagues, as well as officials at other companies, defend their services. They say their estimates are very reliable and focused primarily on preventing disease — not creating some kind of master race.

“I understand. It does sound kind of scary. It sounds like, ‘Oh my God. Is this like Gattaca?'” says Sadeghi of Nucleus Genomics.

“But people want their baby to be like themselves — like a better version of themselves. That’s what parents really want,” he says. “They don’t want some kind of superbaby. And when I think when people understand then suddenly things become much less scary.”

Anxious parents look for reassurance

Christian Ward, 32, a tax accountant who lives in Las Vegas with his wife, signed up for that company’s services primarily to try to cut the chances of having a baby with Type 1 diabetes, which Ward has.

“It’s really difficult to go from a healthy life to then being completely insulin dependent,” says Ward. “It’s just not something that I’d like to pass on to a child. I wouldn’t want my child to be always thinking about their blood sugar and how to manage it.”

But he adds: “It’s kind of trippy to think that you can kind of cycle through and see, ‘Oh, this embryo could potentially have this hair color, this eye color,’ all these other things.'”

His wife, Julia, who’s a nurse practitioner, wants a healthy baby.

“We’re really excited. For us we’re just mainly looking at the medical side of it,” she says. “It kind of keeps you a little bit more calm. Having a new child is sometimes scary. It just gives us a sense of peace with everything.”

Max Reilly, who’s 30 and lives in British Columbia, Canada, signed up for Herasight’s services for similar reasons. He mainly wants to cut the risk of having a child at risk for Alzheimer’s.

“I’ve been exposed to a few people with Alzheimer’s in my life,” he says. “It’s just so tough on people and their loved ones. And to reduce the chances of someone having to go through that and their kids having to go through that is just awesome.”

But he and his wife are also interested in cutting the risk for other diseases, as well as having the smartest children possible.

“It’s hard to imagine not wanting to be, you know, a little bit, a little bit smarter, a little bit sharper,” Reilly says. “It is sort of out of science fiction. It’s just science now. I think it’s sort of incredible technological progress. I think it’s very cool.”

How good are the predictions?

But not everyone thinks this is such a great idea. First of all, it’s expensive. As much as $50,000, plus thousands more for IVF, which is physically grueling and carries risks. Some people get their embryos screened if they’re already going through IVF for infertility. Others do IVF specifically to produce embryos for screening.

“Polygenic risk scores for embryos [are] not yet ready for prime time,” says Dr. Susan Klugman, a medical geneticist who served as the president of the American College of Medical Genetics and Genomics. “Polygenic risk scores for embryos are a new technology. And current evidence doesn’t support their accuracy, their safety or their clinical value. So ethically we worry about misleading patients and overstating what the polygenic risk score can do.”

And that’s especially true for complicated traits like IQ, she says.