Interesting article by David Dobbs in the Atlantic. It is known that people with certain alleles begin to suffer various personality or mood disorders after some traumatic experience. Epigenetics at work. Something in the environment causes a gene to turn on or off.
What Dobbs adds is a discussion of the evolutionary benefits of these alleles. For example, we know why sickle-cell anemia persists. It is found in areas with endemic malaria, and if you have only one copy of the gene, it protects against malaria. Two copies and you die young. The calculus is that, in areas where it is common, the genes save more people from malaria than they kill with sickle-cell anemia. There has been discussion that autism, religiosity, fearfulness of strangers, homosexuality, ADHD, and other personal traits might be evolutionarily useful to the species. Certainly in modern society, it helps a small businessman to have ADHD or an engineer to have Asperger's.
In the case of the current article, Dobbs makes the point that people vary. Some kids thrive in the most horrible of circumstances, and others fall apart at the slightest problem; he follows other researchers in naming the fragile people "orchids," apparently because orchids have to be grown in a hothouse if you live in a cold climate. This makes them seem vulnerable.
Dobbs's point is that if they happen to find themselves in a good environment, they can thrive and do things that are helpful to the species through, for example, "increased novelty-seeking, restlessness of attention, elevated risk-taking, or aggression," and this the evolutionary reason they persist. It's not that, when put in the right situation they do well enough; it's that in that situation they do better than "normals."
He talks a lot about some Rhesus personality studies done in the lab where, a long time ago, they round that monkeys would rather cuddle a foodless towel than a wire rack full of food. Rhesus females in the wild stay with the troop, and teenage males are kicked out. They hand out with other males for a while and then try to get into a new troop. It seems neurotic young males get to stay longer in the home troop than normals or aggressives, because they don't cause any trouble. They mesh into new groups easier and manage to pass on their genes. Bullies do worse.
The Rhesus researchers switched babies between neurotic mothers and nurturing mothers, or abusive and normal. Then they compared the resulting kid monkeys DNA. They found that monkeys with one allele processed seratonin efficiently and with another processed it inefficiently, and this was related to how well the monkey thrived under abuse. It is not one to one. The ones who did best had the good allele and a good mother. Changing the mother makes it somewhat worse. Changing the allele made it worse yet.
If you've been following this blog, you know that I accept this type of reasoning in general but wonder what we would do with it. If we could predict alcoholism or school readiness how would we treat kids differently? Dobbs vaguely suggests that we should identify and protect the orchids. I'm not sure how this would be done, but I'm generally in favor of this kind of thing. It's just god-awful hard to know what to do.
I think we should have a wide-spread conversation on how to deal with information about genetic personality susceptibilities.