Fascinating front page article in the Wall Street Journal (also available here) on genetics and IQ, including comments from two honorary degree recipients from Williams, Troy Dunster and Eric Lander.

Last September, Bruce Lahn, a professor of human genetics at the University of Chicago, stood before a packed lecture hall and reported the results of a new DNA analysis: He had found signs of recent evolution in the brains of some people, but not of others.

It was a triumphant moment for the young scientist. He was up for tenure and his research was being featured in back-to-back articles in the country’s most prestigious science journal. Yet today, Dr. Lahn says he is moving away from the research. “It’s getting too controversial,” he says.

Dr. Lahn had touched a raw nerve in science: race and intelligence.

What Dr. Lahn told his audience was that genetic changes over the past several thousand years might be linked to brain size and intelligence. He flashed maps that showed the changes had taken hold and spread widely in Europe, Asia and the Americas, but weren’t common in sub-Saharan Africa.

Controversial stuff. We have touched on related issues at EphBlog on occasion.

As scientific tools for probing genes become increasingly powerful, research into human differences has exploded. Most of the time, scientists are looking for clues about the causes of disease. But some research is raising tensions as scientists such as Dr. Lahn venture into studies of genetic differences in behavior or intelligence.

Pilar Ossorio, a professor of law and medical ethics at the University of Wisconsin, criticizes Dr. Lahn for implying a conclusion similar to “The Bell Curve,” a controversial 1994 bestseller by Richard J. Herrnstein and Charles Murray. The book argued that the lower average performance by African-Americans on IQ tests had a genetic component and wasn’t solely the result of social factors. Referring to Dr. Lahn and his co-authors, Prof. Ossorio says: “It’s exactly what they were getting at. There was a lot of hallway talk. People said he’s doing damage to the whole field of genetics.”

The 37-year-old Dr. Lahn says his research papers, published in Science last September, offered no view on race and intelligence. He personally believes it is possible that some populations will have more advantageous intelligence genes than others. And he thinks that “society will have to grapple with some very difficult facts” as scientific data accumulate. Yet Dr. Lahn, who left China after participating in prodemocracy protests, says intellectual “police” in the U.S. make such questions difficult to pursue.

Research along these lines is not currently conducted at Williams. But might it be one day?

Williams College has been awarded a $145,924 grant from the National Science Foundation for the project “Acquisition of DNA Analysis Instrumentation for Research and Education,” under the direction of Jason A. Wilder, assistant professor of biology.

I’d wager that some of the advantaged alleles that Lahn identified are more likely to be found in Williams students than in the general population. It is an empirical question.

I can’t imagine a faculty member at Williams even discussing in public the possibility of links between genetics and intelligence/behavior next year. A decade from now, there will be no avoiding the topic. The truth will out, eventually.

Professor Troy Duster, a speaker at Williams this past winter, is quoted in the article.

For instance, researchers have found that most Europeans have a genetic variant that lets them fully digest milk as adults. The variant is much less common in Africa and Asia, where lactose intolerance is widespread. Scientists theorize that it spread quickly among Europeans because drinking milk from domesticated dairy animals conferred a nutritional advantage. Similar evolutionary reasoning may explain why many people in malaria-prone parts of Africa carry gene variants linked to malaria resistance.

Other research is starting to explain variations in human skin color and hair texture. But scientists tense up when it comes to doing the same sort of research on the brain. Sociologist Troy Duster, who studies the use of racial categories by geneticists, worries that scientists will interpret data in ways that fit their prejudices. He cites the sorry history of phrenology, a study of skull shapes popular in the 19th century, and other pseudoscientific techniques used to categorize people as inferior. “Science doesn’t transcend the social milieu,” says Dr. Duster, of New York University.

True. Duster sounds like an interesting guy. It is too bad that no one blogged and/or podcasted his talk at Williams.

Henry Harpending, a University of Utah anthropology professor who recently published a theory for why Ashkenazi Jews tend to have high IQ’s, says Dr. Lahn once suggested they co-author an article for Scientific American about the genetics of behavior, in which they could explain why “Chinese are boring.”

“I think that Bruce doesn’t understand political correctness,” Dr. Harpending says. Dr. Lahn says he only vaguely recalls the conversation but confirms that he wonders whether during China’s imperial times there was “some selection” against rebellious individuals.

I wonder what would happen if Lahn mentioned this theory during a talk at Williams.

Dr. Lahn’s group zeroed in on the role of two genes, called ASPM and microcephalin, that are known to have a role in brain size. Humans with defective copies of either gene are born with brains only about one-third the normal size.

Studying DNA from several species, the Chicago team found that, over millions of years, the genes had undergone more rapid change in monkeys, apes and humans than in other animals. Their next step was to determine if evolution had continued in modern humans. Dr. Lahn’s graduate students began decoding DNA from 1,184 people belonging to 59 groups from around the world, including Bedouins, Pima Indians and French-speaking Basques.

The data showed that evolution had continued in recent millennia. A statistical analysis of DNA patterns suggested that new mutations in each of the two brain-related genes had spread quickly through some human populations. Evidently, these mutations were advantageous among those populations — just as the genetic variant promoting milk digestion was advantageous to early Europeans. Dr. Lahn and his team further observed that the new mutations are found most frequently outside of Africa.

What the data didn’t say was how the mutations were advantageous. Perhaps the genes play a role outside of the brain or affect a brain function that has nothing to do with intelligence.

While acknowledging that the evidence doesn’t permit a firm conclusion, Dr. Lahn favors the idea that the advantage conferred by the mutations was a bigger and smarter brain. He found ways to suggest that in his papers. One mutation, which according to his estimates arose some 40,000 years ago, coincided with the first art found in caves, the paper observed. The other mutation, present mostly in people from the Middle East and Europe, and estimated to be 5,800 years old, coincided with the “development of cities and written language.”

That suggested brain evolution might have occurred in tandem with important cultural changes. Yet because neither variant is common in sub-Saharan Africa, there was another potential implication: Some groups had been left out.

Commencement Speaker Eric Lander is not a fan.

Dr. Lahn’s paper and talk at his university — in which he also claimed the gene variants were probably linked to higher IQ — provoked a strong reaction both on and off campus. Dr. Collins, head of the federal genome program, obtained advance copies of the papers and circulated them to top population geneticists. He wasn’t persuaded by the statistical evidence for evolution and criticized Dr. Lahn’s work in media interviews.

The papers won wide attention among researchers, and several responded by setting out to test Dr. Lahn’s findings. Scientists at the Broad Institute, a top genetics center in Cambridge, Mass., have been reanalyzing some of the data and say they may challenge Dr. Lahn’s finding that evolution acted on ASPM, one of the genes. Broad’s influential chief, Eric Lander, says scientists probing recent evolution run the risk of “seeing a difference, and saying there is a story to fit it.”

Ephs interested in keeping up on this topic should read Gene Expression, the best single source for updates.

More recently, Dr. Lahn says he was moved when a student asked him whether some knowledge might not be worth having. It is a notion to which he has been warming.

I often feel the same. But, most days, I can’t help trying to live up to the example set by my professors at Williams. Knowledge is often painful and awkward and disquieting, but that is no excuse for averting our eyes.

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