Researchers analyzing the connection between genetics and depression have recently made a discovery that challenges recent findings, but lends additional credence to an earlier theory. It would appear that genes do play a critical role in underlying people's susceptibility to experiencing depression.
With this new conclusion, experts behind the work go up against a 2009 study, which indicates that the genetic link is unfounded, and non-existent. This study is bound to reignite a heated debate in the international scientific community.
Experts from the University of Michigan Health System handled the new research effort, details of which were published online in the latest issue of the esteemed journal Archives of General Psychiatry.
It would appear that the new conclusions in fact support a 2003 research, which showed that genes involved in the regulation of the neurotransmitter serotonin are connected to a person's ability, or lack thereof, to rebound from serious emotional trauma.
The inability to do so may force people in a downward spiral towards depression, seeing how they cannot recuperate from the trauma and shock that past experiences brought onto them, PsychCentral
The 2003 research, published in Science, was heralded as a “very important discovery and a real advance for the field,” by the director of the US National Institute of Mental Health (NIH).
But the 2009 study dampened this enthusiasm. Published in the Journal of the American Medical Association (JAMA), the work combined the conclusions of 14 different investigations, to reveal that the genetic link may not be there at all.
In the brand-new investigation, the UMMS team managed to create a much broader survey of all the follow-up studies that were carried on this issue to date. The group was led by assistant professor of psychiatry Srijan Sen, MD, PhD.
A total of 54 researches carried out between 2001 and 2010 were taken into account. The works covered some 41,000 people among themselves, which means that the survey is the largest one on serotonin gene’s relationship to depression.
“When we included all the relevant studies, we found that an individual’s genetic makeup does make a difference in how he or she responds to stress,” Sen explains.
“The major strength of the analysis is that it is the first such work that included all studies that were available on the topic,” explains Institute of Psychiatry in London clinical lecturer Rudolf Uher, PhD.
“And it gives a very clear answer: the ‘short’ variant of the serotonin transporter does make people more sensitive to the effects of adversity,” he goes on to say.