Slashdot Mirror
Massive Study Searching For Genes Behind Intelligence Finds Little
An anonymous reader writes: It's been taken for granted that science would, one day, figure out what parts of our DNA make us smart (or not). But a huge new study done by a group of almost 60 researchers using genome data on over 100,000 people has come up empty-handed. The scientists first looked for differences in the genome that correlated with academic achievement. After narrowing it down to 69 individual sites, they gave cognitive tests to separate group of 24,000 people and looked for evidence of difference at those same locations (abstract). Most of the sites weren't significantly different from chance — the (already weak) genetic influence of genes on height has an effect 20 times greater. On top of that, the three gene locations that did seem to have a stronger correlation weren't involved in development of the nervous system.
The counterpoint here is twin studies. Identical twins, born to the same parents, but adopted by different families, tend to have extraordinarily unlikely similarities in adult general intelligence scores. What this study has been undermining is the notion that because it tracks from birth, it has mostly to do with genes.
Instead, this suggests there are other conditions that identical twins share besides genes. As I said in my earlier post, a lot of expertise has been focused on in-utero development instead.
It's actually a rather decent book. You should read it. It has other insights which are equally
intriguing. Like the fact that most people's friends and coworkers tend to be close in intelligence,
socioeconomics, etc... Most people with college degrees are surrounded by people with
college degrees. Heck, 1 in 5 people don't graduate from HS but if you have a college degree
I doubt you can name a single friend you have that doesn't have a HS degree and I would be
very surprised if you could name 5 unless you happen to work in an occupation that crosses
boundaries. This clumping is probably just as much a factor as many other factors people
tend to look at. We try to pretend we have a classless society but when a person with a
130 IQ only hangs around with other people with a 130 IQ they get a very skewed view of the
world.