Influence of life stress on depression: moderation by polymorphism in 5-HTT gene [pdf]

An interesting read for those interested in psychology, epigenetics or both.

5-HTT has a polymorphism that some people have two short alleles (short-short) some have long alleles (long-long) and some have one short and one long (short-long) allele.

This research found that those who had short-short or short-long alleles and were also maltreated as children were more likely to have major depressive disorder than those who had the same gene combo and no childhood maltreatment or those who had childhood maltreatment and the long-long allele combination. The research showed that having the gene was not enough to predict an episode of depression, nor was the presence of childhood maltreatment. Instead, a specific combination of gene configuration and environmental events predicted depression.