mRNA-seq for cognitive trait analysis
Recently I read about a number of studies that have been frustrated in their attempts to find the genes associated with extreme intelligence.
This article, in particular, highlights the difficulties in pinning down genius.
There might be an evolutionarily conserved reason why genius is not trivially linked to genes. For example, there is a negative correlation between high intelligence and fertility. However, high intelligence members of a society give that society tremendous advantages. How can an organism select for high intelligence, while also selecting against it?
One mechanism is epigenetics. It would make sense if high intelligence was something that could be “switched on” in circumstances that required it, and also “switched off” — or else the population would suffer a decline.
Therefore, when looking for the traits that lead to cognitive differences, it seems quite likely that a large number of these traits are epigenetic, not solely genetic. That we select for genes that have the capacity for intelligence, but they still need to be “activated” — by the appropriate environmental stressors.
Rather than looking at the genetic roots, perhaps the first step should be establishing the pathways of genius, using a combination of mRNA sequencing, and methyl-seq.
On the mRNA-seq front, obviously the ideal would be a brain-biopsy of deceased geniuses to look for gene expression — but circulating plasma can tell you a lot about what’s going on in the body too.
I could find at least one study that demonstrates the use of methyl-seq and mRNA seq in order to probe the epigenetics of the brain.
To probe the genetics of genius, I suspect this will be the path to a successful result — much as it may be disappointing to eugenicists everywhere.
