Depression genes debunked: analysis dashes highly studied link

Research out of the University of Colorado Boulder has dashed research into a potential link between certain genes and depression. The conclusion follows an analysis of both survey and genetic data from more than half a million people, which found that 18 candidate genes and random genes were equally associated with cases of depression.

The new study, which was recently published in the American Journal of Psychiatry, looked at 18 highly-studied 'candidate genes,' each of which had previously been studied in association with depression a minimum of 10 times. The results were called "a little bit stunning" by study senior author Matthew Keller.

According to the study, these 18 candidate genes weren't associated with depression more than other randomly chosen genes. Past research into the genes that had indicated a link between the two were called false positives, though the researchers caution that this doesn't mean depression isn't heritable.

Talking about the results was Institute for Behavioral Genetics researcher and the study's lead author Richard Border, who said in a university release, "This study confirms that efforts to find a single gene or handful of genes which determine depression are doomed to fail."

The findings are a twist on the large body of past research that investigated a potential link between some genes and increased odds developing depression. Such a link would pave the way for specific medications that better target the condition, as well as simple testing to determine whether someone is at increased risk of developing depression.

Unfortunately, it's not that simple, at least according to the new study, with Keller explaining that "depression is influenced by many many variants, and individually each of those has a minuscule effect." However, this conclusion doesn't mean that future studies into the genetic reality of depression should stop — rather, that the existing candidate-gene hypotheses has been 'flawed' all along.