Genius Genes

I have talked before about the fascinating topic of child prodigies, and the continuing debate about the contributions and interactions of nature and nurture.

There is an important new study published in the journal Behavioral Genetics that should be of interest to anyone interested in thinking, intelligence and optimizing the potential of children.

A team of researchers from Washington University School of Medicine in St. Louis, has gathered the most extensive evidence to date that a gene that activates signaling pathways in the brain influences at least one kind of intelligence. They have confirmed a link between the gene, CHRM2 and performance IQ, that involves a person’s ability to organize thoughts or events logically.

The team found that several variations within the CHRM2 gene could be correlated with slight differences in performance IQ scores, which measure a person’s visual-motor coordination, logical and sequential reasoning, spatial perception and abstract problem solving skills. When people had more than one positive variation in the gene, the improvements in performance IQ were cumulative.

Typical IQ tests also measure verbal skills and typically include many subtests. For this study, subjects took five verbal subtests and four performance subtests, but the genetic variations influenced only performance IQ scores.

The researchers studied DNA gathered as part of the Collaborative Study on the Genetics of Alcoholism (COGA). In this multi-center study, people who have been treated for
alcohol dependence and members of their families provide DNA samples and investigators have isolated DNA regions related to alcohol abuse and
dependence as well as a variety of other outcomes.

Some of the participants in the study also took the Wechsler Adult Intelligence Scale-Revised, a traditional IQ test. Members of 200 families, including more than 2,150 individuals, took the Wechsler test, and those results were matched to differences in individuals’ DNA.

By comparing individual differences embedded in DNA, the team focused on CHRM2, a muscarinic receptor gene on
chromosome 7. The CHRM2 gene activates a multitude of signaling
pathways in the brain involved in learning, memory and other higher
brain functions. The research team does not yet understand how the gene
exerts its effects on intelligence.

Intelligence was one of the first pscyhological factors that attracted the attention of people interested in the interplay of genes and environmental influences. Early studies of adopted children showed that when children grow up away from their biological parents, their IQs are more closely correlated to biological parents, with whom they share genes, than adoptive parents, with whom they share an environment.

But in spite of the association between genes and intelligence, it has been difficult to find specific variations that influence intelligence. The genes identified in the past were those that had profoundly negative effects on intelligence – genes that cause mental retardation, for example. Those that contribute to less dramatic differences have been much harder to isolate.

The St. Louis team is not the first to notice a link between intelligence and the CHRM2 gene. In 2003, a group in Minnesota looked at a single marker in the gene and noted that the variation was related to an increase in IQ. A more recent Dutch study looked at three regions of DNA along the gene and also noticed influences on intelligence. In this new study, however, researchers tested multiple genetic markers.

The lead investigator in St. Louis, Danielle Dick, had this to say,

“This is not a gene FOR intelligence, it’s a gene that’s involved in some kinds of brain processing, and specific alterations in the gene appear to influence IQ. But this single gene isn’t going to be the difference between whether a person is a genius or has below-average intelligence.”

“One way to measure performance IQ may be to ask people to order pictures correctly to tell a story. A simple example might be pictures of a child holding a vase, the vase broken to bits on the floor and the child crying. The person taking the test would have to put those pictures into an order that tells the story of how the child dropped the vase and broke it and then cried.”

“If we look at a single marker, a DNA variation might influence IQ scores between two and four points, depending on which variant a person carries. We did that all up and down the gene and found that the variations had cumulative effects, so that if one person had all of the ‘good’ variations and another all of the ‘bad’ variations, the difference in IQ might be 15 to 20 points. Unfortunately, the numbers of people at those extremes were so small that the finding isn’t statistically significant, but the point is we saw fairly substantial differences in our sample when we combined information across multiple regions of the gene.”

Most experts believe that there are at least 100 genes that could influence intelligence, but it is unlikely that any one gene is going to be the ONE determinant of how smart someone is. After all, IQ itself has very poor predictive value for anything much in life apart from achievement in high school. The many genes involved probably have small, cumulative effects on increasing or decreasing IQ, and the key will be to understand the interaction between environmental influences and these genes. We already know that childhood nutrition, socio-economic status and emotional and cognitive environments have a profound influence on intelligence and achievement. Altogether too many children have all the mental machinery but do not even realize the possibilities open to them.

It is also clear that early influences will have a lot to do with the repertoire of intelligences that a person has. In the book and CD series Healing, Meaning and Purpose I spend some time discussing Howard Gardner’s important concept of multiple intelligences. Many of us have skills in certain domains and it is a terrible mistake to assume that because a child is not very good at logical or verbal tasks, that they are not smart. After all, how many brilliant musicians, computer scientists and entrepreneurs never finished high school or college?

There is clearly more than a gene deciding our intelligence and success at certain activities. The genes may give us the machinery and the fuel, but there are clearly many other factors. I’ve always been a very keen chess player and I once had a friend who was a nationally ranked contract bridge Master. He would destroy most normal mortals at any card game: including me! Even when we played scratch games of contract bridge he would always try to avoid partnering me: he told me that I sucked too badly! 8-(

He also had a hobby: he built and designed all kinds of board games. He used to get upset that whatever the game, if it was played on a board, I almost always won. But here’s the interesting thing: our IQs were virtually identical. But he was murderously good at card games but not at anything involving a board: another refinement of intelligence. I probably did well with board games because I could plan and visualize in three dimensions. My friend had a phenomenal memory for cards that I simply don’t possess.

As the owners of some establishments in Las Vegas once discovered to their glee….

“Intelligence is quickness to apprehend as distinct from ability, which is capacity to act wisely on the thing apprehended.”
–Alfred North Whitehead (English Mathematician and Philosopher, 1861-1947)

“Intelligence is the ability to find and solve problems and create products of value in one’s own culture.”
–Howard Gardner (American Psychologist and Professor at Harvard, 1943-)

“The test of a first-rate intelligence is the ability to hold two opposed ideas at the same time, and still retain the ability to function.”
–F. Scott Fitzgerald (American Writer, 1896-1940)

“To the dull mind all nature is leaden. To the enlightened mind the whole world sparkles and burns.”
–Ralph Waldo Emerson (American Poet and Essayist, 1803-1882)

“It is the sign of a dull mind to dwell upon the cares of the body, to prolong exercise, eating and drinking and other bodily functions. These things are best done by the way; all your attention must be given to the mind.”
–Epictetus (Phrygian-born Greek Stoic Philosopher, c.A.D.55- c.A.D.135)