Genetics and Environment: Are You Depressed?

A good, clear article on the role of genetic predisposition vs. upbringing and occurrence of depression lives at Psychology Today in The Identity Dance. Although there are genes that may suggest a higher chance of developing certain mental illnesses, including depression, your upbringing has a lot to do with how likely you are to succumb during trigger events.

The results were striking: 43 percent of subjects who had the short genes and who had experienced four or more tumultuous events became clinically depressed. By contrast, only 17 percent of the long-gene people who had endured four or more stressful events wound up depressed—no more than the rate of depression in the general population. People with the short gene who experienced no stressful events fared pretty well too—they also became depressed at the average rate. Clearly, it was the combination of hard knocks and short genes that more than doubled the risk of depression.

... Moffitt and Caspi have found a similar relationship between another gene and antisocial behavior. Abused and neglected children with a gene responsible for low levels of monoamine oxidase in the brain were nine times more likely to engage in violent or other antisocial behavior as adults than were people with the same gene who were not mistreated. Finnish scientists have since found similar effects on genes for novelty seeking—a trait associated with attention deficit hyperactivity disorder. Children who had the genes and who were also raised by strict, emotionally distant parents were much more likely to engage in risky behavior and make impulsive decisions as adults than children with the same genes who were raised in more tolerant and accepting environments.

The saddest part of the article is the alcoholic monkey, though.