Zhao Bowen is late for a Satanic heavy metal concert. After haggling the doorman down to half price, he pushes into a Beijing bar with a ceiling low enough to punch. He follows the shriek of guitars down a corridor and into a mosh pit lit by strobe lights. It's hot as hell and looks like it too: Men onstage made up as demons are slashing through a song about damnation—the lyrics are in English—while headbangers worship at their feet. Zhao dives in.

The strobes capture midair collisions of bodies, sprays of sweat. Someone's glasses fly off and are crushed underfoot. Over the faces of the onlookers spreads that distinctive look of thrill and fear that tends to presage a riot. But just then the song climaxes in a weird screamgasm and the band takes a break. The crowd responds with the ultimate compliment, chanting "Niu bi! " and pumping their fists. The phrase can be roughly translated as "fuck yeah!" but it literally means "cow's vagina."

Zhao blends right in with all the Chinese teenagers in this sweltering rock dungeon. He has big wide-set eyes framed by dark eyebrows and a pair of silvery geek glasses. It makes him look like a friendly cartoon character, and the effect is enhanced by full cheeks that make his head look spherical. He is neither strikingly handsome nor unattractive. Zhao is of average height, average weight.

But he is far from average. After being identified early as a science prodigy, Zhao raced through China's special programs for gifted students and won a spot in Renmin, one of the country's most elite high schools. Then, to the shock of his friends and family, he decided to drop out when he was 17. Now, at 21, he oversees his own research project at BGI Shenzhen—the country's top biotech institute and home to the world's most powerful cluster of DNA-sequencing machines—where he commands a multimillion-dollar research budget.

Zhao's goal is to use those machines to examine the genetic underpinnings of genius like his own. He wants nothing less than to crack the code for intelligence by studying the genomes of thousands of prodigies, not just from China but around the world. He and his collaborators, a transnational group of intelligence researchers, fully expect they will succeed in identifying a genetic basis for IQ. They also expect that within a decade their research will be used to screen embryos during in vitro fertilization, boosting the IQ of unborn children by up to 20 points. In theory, that's the difference between a kid who struggles through high school and one who sails into college.

Zhao doesn't talk about work tonight. He dives in and out of the crowd. He makes small talk with a girl, bums a cigarette off her. Tonight Zhao is a normal young adult. Tomorrow he will return to his multimillion-dollar experiment—one whose success could complicate the whole idea of what it means to be normal.

Some people are smarter than others. It seems like a straightforward truth, and one that should lend itself to scientific investigation. But those who try to study intelligence, at least in the West, find themselves lost in a political minefield. To be sure, not all intelligence research is controversial: If you study cognitive development in toddlers, or the mental decline associated with Alzheimer's disease, "that's treated as just normal science," says Douglas Detterman, founding editor of Intelligence, a leading journal in the field. The trouble starts whenever the heritability of intelligence is discussed, or when intelligence is compared between genders, socioeconomic classes, or—most explosively—racial groupings.

Since the 1990s, when a book called The Bell Curve (coauthored by a psychologist and a political scientist) waded into this last morass, attempts to quantify or even study intelligence have become deeply unfashionable. Dozens of popular books by nonexperts have filled the void, many claiming that IQ—which after more than a century remains the dominant metric for intelligence—predicts nothing important or that intelligence is simply too complex and subtle to be measured.

David Hogsholt

For the most part, an IQ test—the most common of which today is called the Wechsler Adult Intelligence Scale—is a series of brainteasers. You fit abstract shapes together, translate codes using a key, sort numbers or letters into ascending order in your mind. It's a weirdly playful exercise, the sort of test you would expect to have no bearing on anything else. But studies make it clear that IQ is strongly correlated with the ability to solve all sorts of abstract problems, whether they involve language, math, or visual patterns. The frightening upshot is that IQ remains by far the most powerful predictor of the life outcomes that people care most about in the modern world. Tell me your IQ and I can make a decently accurate prediction of your occupational attainment, how many kids you'll have, your chances of being arrested for a crime, even how long you'll live.

Critics claim that these correlations are misleading, that those life outcomes have more to do with culture and environmental circumstances than with innate intellectual ability. And even IQ researchers are far from in agreement about whether scores can be validly compared between groups of people—men and women, blacks and whites—who experience very different environments even within the same country. Variations within groups are often greater than the variations between them, making it impossible to draw conclusions about someone based on their group.

But on an individual level, the evidence points toward a strong genetic component in IQ. Based on studies of twins, siblings, and adoption, contemporary estimates put the heritability of IQ at 50 to 80 percent, and recent studies that measure the genetic similarity of unrelated people seem to have pushed the estimate to the high end of that range.

This is an idea that makes us incredibly uncomfortable. "People don't like to talk about IQ, because it undermines their notion of equality," Detterman says. "We think every person is equal to every other, and we like to take credit for our own accomplishments. You are where you are because you worked hard." The very idea of the American dream is undermined by the notion that some people might be born more likely to succeed. Even if we accept that intelligence is heritable, any effort to improve or even understand the inheritance process strikes us as distasteful, even ghoulish, suggesting the rise of designer superbabies. And given the fallout that sometimes results when academics talk about intelligence as a quantifiable concept—such as the case of Harvard president Lawrence Summers, who in 2006 resigned after suggesting that science is male-dominated due not to discrimination but to a shortage of high-IQ women—it's no surprise that IQ research is not a popular subject these days at Western universities.

But in his lab at BGI, 21-year-old Zhao has no such squeamishness. He waves it away as "irrational," making a comparison with height: "Some people are tall and some are short," he says. Three years into the project, a team of four geneticists is crunching an initial batch of 2,000 DNA samples from high-IQ subjects, searching for where their genomes differ from the norm. Soon Zhao plans to get thousands more through Renmin—his former high school—as well as from other sources around the world. He believes that intelligence has a genetic recipe and that given enough samples—and enough time—his team will find it.

Zhao's improbable rise at BGI began in the summer of 2009, when one of the firm's founders, a geneticist named Wang Jian, noticed a skinny stranger lurking in the hall. "Hey, what are you doing here?" Wang asked the high school student with a spiky mess of hair. Zhao was 17, and he was there taking part in BGI's science summer camp. "Why aren't you in class?" Wang pressed.

"It's boring," Zhao said.

David Hogsholt

Wang took an immediate liking to him. On a hunch, he pushed Zhao into the hands of Li Yingrui, a recent college dropout who was already one of BGI's leading scientists. "Do you know any Perl?" Li asked him. Perl is a programming language often used to analyze genomic data. Zhao admitted he did not; in fact, he had no programming skills at all. Li handed him a massive textbook, Programming Perl. There were only two weeks left in the camp, so this would get rid of the kid for good.

A few days later, Zhao returned. "I finished it," he said. "The problems are kind of boring. Do you have anything harder?"

Perl is a famously complicated language that takes university students a full year to learn. So Li gave him a large DNA data set and a complicated statistical problem. That should do it. But Zhao returned later that day. "Finished." Not only was it finished—and correct—but Zhao had even built a slick interface on top of the data.

The next morning Li marched into Wang's office. "This guy is a genius," he said. "You have to keep him." So Zhao dropped out of high school, said good-bye to his mother and father—he is an only child, like most Chinese of his generation—and moved to Shenzhen to begin a new life.

Despite Wang's open-door policy for young dropouts, BGI doesn't provide much of a safety net for its incoming prodigies. Zhao had a rough arrival. His starting salary was minimal. He had no friends. "It was hard," he admits. It was also crazy. Zhao didn't drop out of just any high school. He dropped out of Renmin, one of the best prep schools in China. He had won his place there by acing a series of academic tests when he was in sixth grade. Zhao seemed to be forfeiting his future. He asked his parents for their blessing and they agreed, but with one condition: He had to get permission from Renmin.

The Renmin principal, Liu Pengzhi, had watched Zhao's growth with pride; she had identified him early as one of the school's—and hence the country's—most gifted science students. She flew down to Shenzhen to tour BGI and meet Wang in person. Only then did she give Zhao her official approval, as well as a parachute: "If you change your mind, you can come back to Renmin and finish your studies anytime," she told him.

Ask Zhao what draws him to IQ as a research subject and invariably he talks about the mysteries of the brain. He's driven by a fascination with kids who are born smart; he wants to know what makes them—and by extension, himself—the way they are. But there's also a basic pragmatism at work. By way of explanation, he points to the International Mathematical Olympiad, a tough competition that has helped define China's approach to math. Two-thirds of students train for it, he says, and its judgment of the talent is so respected that for years high scorers were allowed to skip gaokao, the traditional college entrance exam. But only a tiny fraction of people have the mathematical gifts to be competitive, Zhao says, and this basically comes down to IQ. "You cannot ask a kid with low IQ to just work hard and then become a really talented mathematician," he says. "It's impossible." And yet, Zhao says, that's what is currently expected in China. He wants to stop the vast majority of Chinese students from wasting their time.

Three years after arriving at BGI, Zhao's messy mop of hair is gone, replaced by a dark shadow across his shaved scalp. His project, meanwhile, has grown up along with him. Just a week before my visit, thousands of DNA samples arrived at the institute, each containing the genome of a person with extraordinarily high IQ. They were collected from volunteers around the world by Robert Plomin, a behavioral geneticist at King's College London who is now one of the project's main collaborators. Once these samples are processed, BGI's battery of DNA sequencers will decode them.

The customized Baby

Whether we like it or not, parents with the motivation—and cash—will one day be able to select traits for their darling offspring. We can already detect scores of genetic diseases early by screening embryos created in vitro. And the more we learn about the genome, the more traits we'll be able to select for or against. Here's a menu of superbaby options, from the possible to the farcical. —Katie M. Palmer

Already Possible

Avoiding Tay-Sachs

Like many diseases that are screened for during IVF, Tay-Sachs is caused by a single mutation: in this case, in the HEXA gene, which when altered renders the body unable to create an enzyme that breaks down fat in the brain.

Avoiding albinism

Destructive but not fatal, the most common form of albinism is caused by a mutation in a gene for the skin pigment melanin. Like Tay-Sachs, it's a classic one-gene trait.

Reducing breast-cancer risk

US women have roughly a 12 percent chance of getting breast cancer, but a mutation of the BRCA1 tumor-suppressing gene vaults risk to 60 percent.

Maybe Someday?

Enhancing athletic ability

A kid's chances of becoming an elite athlete depend on a number of traits—strength, power, endurance. Each of these has been proven to be at least partly heritable, but the clearest connection is between the gene ACTN3 and explosive strength.

Avoiding autism

Heritability of spectrum disorders is currently estimated at around 38 percent. Roughly 50 related genes and 30 gene locations have been discovered—all of which may ultimately be used for selection.

Reducing obesity

Some 40 to 75 percent of obesity cases can be accounted for by genes. About 5 percent can be tied to specific mutations that are relatively easy to select against. For the rest, there are dozens of identified variants, each with a small individual effect.

Avoiding psychopathy

Traits of psychopathy are estimated to be about 50 percent heritable, and dimensions of this disorder—grandiosity, callousness, and impulsivity—have similar genetic components.

Enhancing height

Stature is between 60 and 80 percent heritable, with hundreds of the genetic variants identified so far. Eventually, as with IQ, whole-genome sequencing of embryos could allow parents to pick the tallest offspring of the batch.

Choosing sexual orientation

The fact that sexual orientation is influenced by genetics has been well established: Studies of siblings, twins, and adoptees suggest that genes account for at least half of the variation.

Choosing a political leaning

A 2011 study looked at differences between conservative and liberal leanings—and found, surprisingly, three areas that might be linked to political predisposition. But it will be a good long time before we can genetically nudge our kids to share our politics.

The project has already weathered at least one serious false start. Zhao's original plan made sense on paper: Get IQ scores and DNA samples from a large number of smart people, compare their genomes to normal people, and after some statistical magic, voilà! The genetic markers for IQ would pop right out. So Zhao returned, naturally, to Renmin, the high school he had just abandoned. He worked with Yang Rui, a brilliant Renmin graduate who had worked on the human genome project at BGI as a teenager. Zhao knew nothing about psychometrics, the branch of psychology behind the IQ test. Yang's psychometric research at Yale and Brown universities made her the perfect collaborator.

But they ran up against an unexpected problem: There was no Chinese IQ test, and Renmin students' English skills weren't consistent enough to conduct the test in English. Moreover, the IQ test is supposed to be given as a one-on-one interview, so when Zhao and Yang tried to administer it to whole classes of students at once, the result was chaos and useless data. Worst of all, getting blood samples from students proved nearly impossible, as wary parents began to raise alarms. Principal Liu had to call a meeting with parents to calm their nerves. The collaboration with Renmin was quietly put on hold.

The fortunes of the research effort changed in October 2010, when Zhao met Steve Hsu, a professor who was spending a year in Taiwan while on sabbatical from the University of Oregon. (He is now vice president for research and graduate studies at Michigan State University.) A theoretical physicist who likes to apply his mathematical muscles to a wide range of complex problems, Hsu was intrigued by a news article about BGI that briefly mentioned Zhao's project. A few emails later, he flew over to give a talk at BGI and soon became a permanent collaborator and adviser to the team.

Since most of the variation in IQ is heritable, scientists have long searched for genetic differences that might account for it. The reason we haven't found them, Hsu theorizes, is because there aren't any single genes or even a handful of genes with a big effect on IQ. Instead, the thinking goes, there are as many as 10,000 different locations in the genome where a mutation can affect IQ. According to Hsu's rough model, all humans carry a few hundred of those 10,000 possible mutations, and each mutation has a tiny negative cost to IQ, on the order of half an IQ point.

If this is right, then the difference between a brilliant 150-IQ person and an average 100-IQ person comes down to DNA typos at perhaps 100 of those 10,000 places. Other traits—like height, for example—seem to work the same way, and an ongoing study into the genetics of height has begun to find relevant mutations. Most geneticists who have studied intelligence agree with this theory in broad strokes. At the very least, says Kevin Mitchell, a geneticist at Trinity College Dublin in Ireland who studies brain development, Hsu's basic theory of many deleterious mutations "is far more plausible than the alternative"—that is, more plausible than the idea that the mutations are building up IQ, not knocking it down.

David Hogsholt

The only way to unravel the genetics of a trait scattered among 10,000 possible DNA variants is to use something called GWAS (genome-wide association study). Rather than identifying the variants that cause a trait, as can be done with so-called Mendelian traits like finger length or earwax type, you find the variants associated with the trait.

But—and this is crucial—the implications of this math are that it will take far more than a few thousand genomes to solve the puzzle of intelligence. Given the small sample size they have so far, Hsu hopes they'll start by finding one or two genes associated with intelligence. A recent Dutch study required more than 125,000 genomes to isolate three variants associated with educational attainment; to create a genomic predictor of IQ, Hsu says, it could take 1 million or more.

The good news for Zhao is that cheap DNA sequencing, together with more creative ways of obtaining DNA, means that a million genomes could be in reach within five years. The genomes don't all need to be geniuses, because the IQ-affecting genetic markers they're looking for—DNA typos that drag down intelligence—are more often carried by the 100-IQ people. That is, it's a relative dearth of these mutations that gives people higher IQ, according to the theory.

Assuming Zhao and his team succeed, there are implications that will trouble many people. Hsu is confident that through embryo screening during IVF, any genetic markers for intelligence that their team discovered would inevitably be used to select for more intelligent babies. Children tend to fall within a spread of 13 IQ points above and below the average IQ of their parents. But sometimes the apple can fall twice as far from the tree—that is, two parents with 100 IQs producing a child with an IQ of 126. Hsu puts the chance of such a positive outlier at around 2 or 3 percent, and it depends mostly on which sperm meets which egg.

If parents use IVF to conceive, then a genetic test—an extension of the screening tests for genetic diseases that are already routinely done on embryos—could let them pick the smartest genome from a batch of, say, 20 embryos. "It's almost like there are 20 parallel universes," Hsu says. "These are all really your kids." You're just choosing the ones with the greatest genetic potential for intelligence. But effectively, you could be giving an unborn child a boost in IQ above their parents. As Hsu sees it, this is no Faustian bargain. "Aren't we doing them a great service?" Over the long term, he proclaims, this would "improve the average IQ of the species by quite a bit." He hopes governments will even provide it for free; Singapore, he predicts, would be the first to sign up.

Even if Zhao and his team do get enough DNA, the genetics of IQ could prove to be a thornier problem than Hsu and Zhao expect. For example, there's the question of epistasis, or the interaction of genes with one another. Hsu is convinced (based on his reading of the existing data) that IQ mutations are essentially additive, such that the negative pull of each person's DNA typos can simply be tallied up. But it's likely that the effect of some genes will depend on the presence or absence of others, making it much trickier to predict IQ from birth. "The reality," says Mitchell, the Trinity College geneticist, is "probably somewhere in the middle" between simple additivity and complex epistasis; and just where that balance lies will determine whether a genetic IQ prediction machine is ever possible. Even if Mitchell's skepticism is borne out, and the answer is somewhere in between, it still means that an embryonic test could allow parents a significant degree of influence over their offspring's intelligence.

In Shenzhen, when I meet two members of Zhao's team—Chris Chang, a 35-year-old Chinese American statistician, and Laurent Tellier, a 30-year-old Danish bioinformaticist—I ask them the unavoidable question: Would they, as parents, take advantage of this service? Their responses are radically different. "Yes, absolutely," Tellier says, adding that he had decided this years ago after seeing the film Gattaca. (It probably wasn't the takeaway that the filmmakers of that dystopian tale had intended.) Chang, meanwhile, gives a definite no. He declines to give a reason; he just shakes his head.

The last time I see Zhao, I put the same question to him. It's a freezing day in November when he swings through Boston, near where I live, and I meet him at a bar. He's not old enough to legally drink in the United States, but no one cards him. He had spent the afternoon with a Harvard scientist who studies prosopagnosia, a condition that makes it difficult for a person to recognize faces. There's evidence that the disease is strongly heritable, so Zhao and the scientist discussed sequencing the genomes of afflicted families to find the genes. Over our drink, I pose my earlier question to Zhao: Would he use his research to have more intelligent offspring of his own? His response is nuanced. "I understand both positions," he says. "But I will have to respect my wife. It's not only my child. It will be hers too." He worries that some neurological complications, such as Asperger's syndrome, might be genetically tied to IQ.

Not all the ramifications of Zhao's success would be frightening. If studies like this end up shedding light on the genetic architecture of the brain, it could transform mental health, revealing genes that go awry in diseases like schizophrenia and bipolar disorder. Diagnoses could happen earlier; treatments could become more effective. In any case, Zhao prefers to think of his work as basic research, drawing an analogy to physics from a century ago. "You could make something bad, like atomic bombs, or you could make something really good," he says. "But the science itself is neutral, and it has to move on."

Human intelligence is encoded in our genes, he believes, and "someone's going to find it." Why not a boy genius?

John Bohannon (gonzo@aaas.org) wrote about a reality-TV show for Arab inventors in issue 20.02.