Monday, July 29, 2013

China not squeamish about IQ

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.

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.

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.

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.