Sexual reproduction is a genetic crapshoot. Out of hundreds of eggs and millions of sperm, one joins one to produce a baby whose natural endowments could reflect the best traits of both parents—or the absolute worst. To procreate through intercourse is to take a wild roll of the DNA dice. And the stakes could hardly be higher. One stray allele could mean the difference between a healthy baby and one with a debilitating disorder.
What if science offered a way to stack the odds in favor of a healthy, gifted child? The idea is as thrilling as it is alarming. But how realistic is it? Last week, a widely shared story in the magazine Vice suggested it’s imminent and inevitable—just not in the hidebound United States.
The article, headlined “China Is Engineering Genius Babies,” reports that our superpower frenemies in the East have hatched a grand plan to breed a crop of hyperproductive smartypants. Here’s an excerpt:
“At BGI Shenzhen, scientists have collected DNA samples from 2,000 of the world’s smartest people and are sequencing their entire genomes in an attempt to identify the alleles which determine human intelligence. Apparently they’re not far from finding them, and when they do, embryo screening will allow parents to pick their brightest zygote and potentially bump up every generation's intelligence by five to 15 IQ points. Within a couple of generations, competing with the Chinese on an intellectual level will be like challenging Lena Dunham to a getting-naked-on-TV contest.”
You might think that such a sensational report would be received skeptically by readers and dismissed or debunked by the mainstream press. Instead it went viral on Facebook and Reddit and earned top billing in BBC Future’s weekly “Best of the Web” roundup.
In fact, key parts of the story are true—and not just the parts about Lena Dunham doffing her clothes. But large swaths are naïve, misleading, or grossly overstated. And it’s worth sorting through them, because in the not-distant future, it’s conceivable that parents will face a critical choice when it comes to making babies. The choice will be between fertilizing embryos in a lab and analyzing their DNA to try to select and gestate the healthiest possible baby, or doing it the old-fashioned way and leaving the genetics to chance.
Let’s start with what’s not true. China is not “engineering” babies. Even if it were, Chinese scientists wouldn’t know how to genetically engineer a genius. And even if they did know how to genetically engineer a genius, the fact is that you can’t ensure genius, because genius depends on environment as well as genes.
What is true, though, is fascinating, exciting, and troubling. Scientists are already developing the capacity to screen human embryos for a wide variety of genetic disorders, such as cystic fibrosis and sickle-cell anemia. At Reprogenetics, a private laboratory in New Jersey, couples who carry a genetic disease can have their embryos checked for the mutation before implanting them in the woman’s uterus. The process is referred to as preimplantation genetic diagnosis, and the technology is advancing rapidly. Santiago Munné, the lab’s director, told me that within a year he expects to be able to offer embryo analyses that screen for more than 100 diseases at once, for a few thousand dollars.
Women are already using preimplantation analysis to select the gender of their embryos. And in the United States, they’re overwhelmingly choosing to have daughters.
The next leap will be to whole-genome sequencing of embryos. That opens the door to screening not just for sex or single-gene disorders but for more complex disorders like autism—or even, conceivably, qualities like physical attractiveness or intelligence. Munné considers this type of “positive selection” beyond the pale: “Selecting for embryos based on eye color, etc., means you are discarding the others based on traits, and that’s unethical.”