Our genes plays a crucial role in determining our susceptibility to depression, according to a research by University of Michigan.
The new findings have challenged a 2009 study that questioned the genetic link.
Previously, scientists had discovered a connection between a gene that regulates the neurotransmitter serotonin and an individual's ability to rebound from serious emotional trauma, such as childhood physical or sexual abuse.
Srijan Sen, of the University of Michigan Medical School, and colleagues examined 54 studies dating from 2001 to 2010 and encompassing nearly 41,000 participants, before reaching a conclusion.
"When we included all the relevant studies, we found that an individual's genetic make-up does make a difference in how he or she responds to stress," said Sen.
Rudolf Uher, a clinical lecturer at the Institute of Psychiatry in London, said the U-M research will help cut through the debate about the genetic connection and refocus the field on making new advances to help those affected by mental illness.
"The major strength of the analysis is that it is the first such work that included all studies that were available on the topic. And it gives a very clear answer: the 'short' variant of the serotonin transporter does make people more sensitive to the effects of adversity," said Uher.
The new analysis found robust support for the link between sensitivity to stress and a short allele in those who had been mistreated as children and in people suffering with specific, severe medical conditions.
Only a marginal relationship was found in those who had undergone stressful life events.
The findings were published in the journal Archives of General Psychiatry.