Different Minds

New Scientist Nov. 5, 2011

the gene responsible for the serotonin transport gene, SERE, which regulates the move of serotonin - a neurotransmitter curcial to moods, among other things.
In humans and rhesus monkeys, it comes in two forms - "long" and "short". Everybody has two of these genes. People with the long/long combo appear to be protected from very low mood, whereas thos with the short/short or short/long variants are more susceptible to depression.

"The short variant appears to be linked with emotional responsivity. In a stressful environment this seems to increase vulnerability to depression, but in a good and nurturing environment people with this variant are often highly successful, with excellent communication and social skills."

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