'Culture Of We' Buffers Genetic Tendency To Depression

Excerpt from Science Daily, 30 October 2009

'A genetic tendency to depression is much less likely to be realized in a culture centered on collectivist rather than individualistic values, according to a new Northwestern University study.

In other words, a genetic vulnerability to depression is much more likely to be realized in a Western culture than an East Asian culture that is more about we than me-me-me.

The study coming out of the growing field of cultural neuroscience takes a global look at mental health across social groups and nations.

Depression, research overwhelmingly shows, results from genes, environment and the interplay between the two. One of the most profound ways that people across cultural groups differ markedly, cultural psychology demonstrates, is in how they think of themselves...

Collectivist cultures may give individuals who are genetically susceptible to depression a tacit or explicit expectation of social support...

The study compared genetic frequency information and cultural value data across 29 countries (major European countries as well as South Africa, Eastern Europe, South Asia, East Asia and South America). The serotonin transporter gene (STG) that the researchers studied has two variants - a short allele and a long allele. In Western populations, the short allele leads to a phenotype of major depressive episodes when people who carry it experience multiple life stressors.

Previous research shows that nations in the East Asian region have a disproportionate number of short allele carriers, and the Northwestern researchers replicated that finding. They also replicated cultural psychology research demonstrating that nations within East Asia are typically more collectivist.

What surprised them was the robust association they found between the degree of collectiveness of a particular nation and the degree to which a disproportionate number of people carried the short allele of the STG. Collectivistic nations were found to have significantly more individuals who carry the short allele of the STG. Even more remarkably, they found, collectivistic nations, such as East Asia, where nearly 80 percent of the population is genetically susceptible to depression, the actual prevalence of depression is significantly lower than in individualistic nations, such as the United States and Western Europe.

This research strongly suggests that medical doctors need to work with basic scientists to better understand the complex dance that biology and culture play in both mitigating and causing mood disorders, such as depression...

These research findings suggest that culture-based treatments may be equally if not more effective at reducing the risk for depression. Medical doctors who embrace scientific findings of global health trends and human cultures may gain invaluable insights about how our genetic heritage and cultural environments affect human behavior...'