Sunday, April 15, 2012
Smart parents raise smart kids-right?
A large group of scientists running a project with the intriguingly mysterious name, Project ENIGMA, have discover that intelligence is probably affected by our genes to a greater degree than previously thought. The researchers, from all across the globe pooled their resources and their data to look for correlations between DNA and specific brain disorders (the usual- dementia, depression, Parkinson's, schizophrenia, etc). While they came up with some interesting data on the diseased brain, what they inadvertently uncovered was a connection between DNA and brain size, and even more curiously, between DNA and intelligence as measured by standardize IQ tests. IQ tests look for a certain type of intelligence so the data has to be viewed with that in mind, but it appeared that a variant in a gene called HMGA2 may be able to explain differences in individual intelligence. The difference in the HMGA2 was in one DNA letter only; at one point in the gene, the base thymine (usually represented as T), was replaced by a cytosine base (C). People that had the letter C instead of T at a certain location on the gene were more likely to have a larger brain and score higher on the IQ tests.
This finding isn't really an answer to the question of inherited intelligence, but rather the starting point for many questions. Correlation is not the same as causation and the size of the brain, the high IQ score and the genetic change, may all be linked by something else in the brain not yet found. However, the association is interested and the methodology used by Project ENIGMA even more interesting. Because it is difficult to obtain enough tissues in any one lab, to conduct thoroughly sound statistical analysis on genetic variations that only occur in a certain percent of the population, the researchers banded together to pool their brains, literally. All the brain samples and data from each of the participating labs were used to look for associations between genes, brain size, disease risk and IQ test ability. Without the collaboration, the project would not have been possible. The nature of the work and the extent of the collaboration has attracted hundreds of financial contributors that has ensured the success of the work.
So does this mean we should kick back as parents and let nature take its course? Not at all. Intelligence is only useful when harnessed appropriately, and usually (with notable exceptions), that happens through the cultivation of good study habits and the development of some level of self- discipline. When I was doing my PhD, someone told me that it would require one third pure hard work, one third organizational skills and one third smarts. I never forgot that, and found it to be just about spot on not only for my PhD, but for pretty much every piece of work I've done since. Intelligence is only part of the picture.
[JOURNAL REFERENCE-Jason L Stein et al. Identification of common variants associated with human hippocampal and intracranial volumes. Nature Genetics, 2012; DOI: 10.1038/ng.2250]