A meta-study finds the short version of a serotonin transporter gene. Serotonin is a neurotransmitter.
ANN ARBOR, Mich. — University of Michigan Health System researchers have found new evidence that our genes help determine our susceptibility to depression.
Their findings, published online today in the Archives of General Psychiatry, challenge a 2009 study that called the genetic link into question and add new support to earlier research hailed as a medical breakthrough.
The 2009 meta-analysis called into question a 2003 study that found those who suffered physical sexual abuse or other stress were more likely to get depressed if they also had the short version of this serotonin neurotransmitter gene. But using a larger number of study participants from more studies a U Mich team finds a connection between the gene and depression.
Today Srijan Sen, M.D., Ph.D, an assistant professor of psychiatry at the University of Michigan Medical School, and his colleagues are presenting a new, broader analysis of the follow-up studies to date. The U-M team examined 54 studies dating from 2001 to 2010 and encompassing nearly 41,000 participants – making it the largest analysis of the serotonin gene's relationship to depression.
"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," says Sen.
The U-M analysis supports previous findings that individuals who had a short allele on a particular area the serotonin gene had a harder time bouncing back from trauma than those with long alleles.
Once we all get ourselves genetically tested (assuming the US Food and Drug Administration and like agencies in other countries don't ban direct-to-consumer genetic testing) we will be able to find out whether stresses predispose ourselves to depression. Imagine a court ruling on child custody guided by the need to minimize the stress a kid might experience by avoiding a custody grant to an especially stressful parent.
Curiously, the gene version that predisposes to depression is at higher frequency in China even though the rate of depression is thought to be much lower. Read that Wired article for how cultural factors might play a role in keeping depression down in China.
Well, if you are depressed this might seem like a depressing report since you can't (yet) change your genes. But look on the bright side (literally): very bright lights reduce depression in elderly patients. A light box would be worth a try.
|Share |||Randall Parker, 2011 January 03 11:10 PM Brain Depression|